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A Nobel Prize winner sold his medal for $765,000 to pay medical bills

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leon lederman

  • In 2015, Leon Lederman sold his Nobel Prize medal for $765,000 in an auction to help pay medical bills.
  • On Wednesday, Lederman died at a nursing home in Idaho. He was 96.
  • He won the Nobel Prize for physics in 1988.
  • His work was in subatomic particles. He notably discovered one called the Higgs boson, which he called the "God particle."

Leon Lederman once won a Nobel Prize for his work in physics. But in 2015, the University of Chicago professor was forced to auction off his medal for $765,000 to help cover medical bills. 

Lederman, who died at 96 on Wednesday, was known for his work with subatomic particles.

He won the award in 1988, with two other scientists, for the discovery of a subatomic particle called the muon neutrino. He is also known for discovering the Higgs boson particle, which he dubbed the "God particle."

Lederman used his initial prize money to buy a log cabin in Idaho, per the AP. His wife, Ellen Carr Lederman, told the outlet that they moved into to the cabin permanently when Lederman began to experience severe memory loss in 2011. In order to pay for the care necessary to manage his dementia, Ledermann allowed an online auction company to sell his Nobel Prize medal, according to the New York Times

Lederman died on Wednesday at the age of 96 in a nursing home in Idaho. As Vox reported, Medicare, which covers many Americans over the age of 65, does not always cover long-term stays in nursing homes. Vox noted that a private room in a nursing home could cost about $7,698 a month.

"What he really loved was people, trying to educate them and help them understand what they were doing in science," Ellen said of her husband.

Visit INSIDER's homepage for more.

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Stephen Hawking’s doctoral thesis about the origins of the universe will soon be up for auction — and so will his wheelchair

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Stephen Hawking

  • World-renowned physicist Stephen Hawking died in March at age 76.
  • Hawking's doctoral thesis, wheelchair, and 20 other items will be featured at an upcoming auction.
  • His thesis includes notes written after the late scientist was diagnosed with ALS, a disease that caused his paralysis.
  • The auction will also feature a script from one of Hawking's appearances on "The Simpsons" and other scientific papers he published.

An upcoming auction will include 22 of physicist Stephen Hawking's items, including his wheelchair and his doctoral thesis about the origins of the universe. 

Auctioneer Christie's announced the online sale on Monday as part of a larger auction featuring scientific papers by Charles Darwin, Albert Einstein, and Isaac Newton, the Associated Press reported. The items will be on display in London starting October 30, with bids open from October 31 to November 8.

One of five remaining copies of Hawking's 1965 doctoral thesis from Cambridge University will be part of the auction. The work, "Properties of Expanding Universes," is estimated to be worth anywhere from $130,000 to $195,000. More of Hawking's papers — including "Fundamental Breakdown of Physics in Gravitational Collapse" and "Spectrum of Wormholes"— will be sold as well. 

stephen hawking auction thesis

Thomas Venning, the head of books and manuscripts at Christie’s, told the AP that the doctoral thesis reflects both Hawking's scientific achievements and his personal history. The document was signed with shaky handwriting, as Hawking finished it after beginning to show symptoms of amyotrophic lateral sclerosis (ALS), which eventually left him paralyzed.

Hawking was diagnosed at age 22, just after starting his doctoral studies, and doctors initially said he would only live a few more years. The scientist lived decades beyond the prognosis, and he died in March at age 76.

As the disease progressed, Hawking began using a wheelchair and communicating with others using a voice-generating computer. The wheelchair, estimated to be worth between $13,000 and $19,500, is included in the sale. The money made during the auction will go toward the Motor Neurone Disease Association and the Stephen Hawking Foundation, which supports research related to both physics and the disease.

Venning told the AP that Hawking's wheelchair symbolizes the scientist's "puckish sense of humor." In 1977, for example, Prince Charles reportedly got his toes crushed beneath Hawking's wheelchair, and the scientist joked that he regretfully did not get a chance to run over Prime Minister Margaret Thatcher's feet as well.

Stephen Hawking auction

Hawking also appeared on "The Simpsons" multiple times, and the upcoming auction will include a script from one of his show appearances. 

In addition to publishing numerous scientific papers, Hawking wrote books, and his popular "A Brief History of Time" will be at the auction. The copy comes with a bomber jacket that Hawking once wore.

Lucy Hawking, the late physicist's daughter, told the AP that the auction will give “admirers of [Hawking's] work the chance to acquire a memento of our father’s extraordinary life in the shape of a small selection of evocative and fascinating items."

SEE ALSO: Stephen Hawking warned that machines are getting smarter than ever, and dismissing it could be our worst mistake

SEE ALSO: Stephen Hawking: Humans need to leave Earth or risk being annihilated by nuclear war or climate change

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This mind-melting thought experiment of Einstein's reveals how to manipulate time

A 'mind-boggling' telescope observation has revealed the point of no return for our galaxy's monster black hole

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supermassive black hole gas accretion disk illustration sagittarius a prime milky way active galactic nuclei eso1835a

  • A black hole 4 million times as heavy as the sun lurks at the center of the Milky Way galaxy.
  • Telescopes just took the best-ever observations of hot gas circling the edge of the black hole.
  • The gas burst out three powerful flares as it zipped around and fell toward the black hole at about 30% of the speed of light.
  • Astronomers described the observations as "mind-boggling" and the closest-ever look at the edge of a monster black hole.

Astronomers just observed the supermassive black hole at the center of the Milky Way galaxy sucking blobs of hot gas toward their doom at 30% of the speed of light.

That's an incredible 201 million mph, which was enough to trigger three powerful bursts of radiation from the cloud. Researchers detected the flares using the Very Large Telescope array in Chile.

Scientists behind the observations of Sagittarius A* (pronounced "A-star"), as the monster black hole is known, say the data is a "mind-boggling" closest-ever look near the edge of a black hole.

It's not the traditional point of no return, called the event horizon— from which light cannot escape — but a physical one where if anything made of matter teeters too close, it will begin an inescapable death spiral.

The group published a study of its work on Wednesday in the journal Astronomy & Astrophysics.

"Astronomers have observed material as close as you can get to a black hole without being consumed by it,"Josephine Peters, an astrophysicist at the University of Oxford who wasn't involved in the study, told Business Insider in an email.

Though Sagittarius A* "is our closest supermassive black hole, it is still incredibly mysterious," she added. "This marks the beginning of understanding more about our nearby astronomical monster."

Staring the 'monster' of the Milky Way in the eye

sagittarius a prime milky way center supermassive black hole active galactic nuclei agn eso0846aSagittarius A* is thought to be a black hole about 4.1 million times the mass of our sun, or 1.3 trillion times the mass of Earth.

But proving either of those two things is tricky, since the presumed black hole is some 25,000 light-years from Earth. It's also practically invisible — the gravity of black holes is so strong that not even light can escape beyond their event horizons, where Albert Einstein's calculations of the universe fall apart and Stephen Hawking's begin.

However, knowing as much about Sagittarius A* as possible is crucial for several good reasons.

On big scales, it's a window into the history and evolution of the Milky Way galaxy, which rotates its spiral arms of hundreds of billions of stars about the giant black hole at its center. That galactic story is also intimately tied to the emergence of the solar system and life itself. (Huge black holes also lurk at the centers of many of the hundreds of billions of other galaxies in the visible universe, some of which may harbor aliens.)

There's also a weirder utility to studying the closest supermassive black hole we know of: It's a laboratory for the physical laws of the universe. It is so massive and spins so rapidly that it dramatically warps and twists space-time and accelerates objects to relativistic or near-light-speed.

Nature gets very, very weird when this happens, but it's nowhere near Earth. So being able to watch it, even from tens of thousands of light-years away, is like having a front-row seat to the cutting edge of human knowledge.

That's why astronomers aimed an instrument called Gravity at Sagittarius A*.

Very Large Telescope four lasers 5

In uncomplicated terms, Gravity combines the light harvested by four telescopes, each with a 30-foot diameter, in the VLT array in Chile, operated by the European Southern Observatory.

Gravity does so as a super-precise, super-cooled instrument that allows researchers to extract more information from the incoming light, turning the array into one very powerful virtual telescope equivalent to 425 feet in diameter.

This extra resolving power helped astronomers peer at a plane of gas and dust falling toward Sagittarius A*, a feature called an accretion disk. The disk is about 100 million miles wide, or a little wider than Earth is distant from the sun.

The Gravity tool helped the team look for flares of infrared light, which astronomers had seen for more than a decade. But this time, with incredible resolving power, they tried to stare at the innermost edge of the disk.

During observations on the nights of May 27, July 22, and July 28, Gravity saw three flares, one after another, in a clockwise pattern. The data suggested the flares came from a blob of hot gas circling the black hole.

"As a cloud of gas gets closer to the black hole, they speed up and heat up," Peters said. "It glows brighter the faster and hotter it gets. Eventually, the gas cloud gets close enough that the pull of the black hole stretches it into a thin arc."

This happened just outside the event horizon, in an area that astronomers refer to as a physical point of no return, called the "innermost stable circular orbit" or ISCO, a region not yet observed before.

Move a blob of matter closer than the ISCO, the thinking goes, and it can't escape. The gravity of a black hole will accelerate the blob of matter, giving it more energy, which will, as Einstein's work explains, give it a stronger gravitational force. This then pulls it faster toward the black hole, creating a feedback loop of relativistic physics that ends in oblivion.

What the edge of our supermassive black hole might look like

The event observed by astronomers is shown in the ESO's image at the top of this story, though it's not a photograph, but a visual simulation that uses data collected by Gravity and other telescopes. Orange shows what researchers think is the blob of superheated gas, or plasma, while blue shows radiation that bleeds off the matter and occasionally bursts into bright flares.

The image also illustrates the bending and distortion of light caused by the black hole warping space-time with its concentrated mass, an effect called gravitational lensing.

ESO also created an animation of the gas cloud and flares: 

The flares were seen on Earth in infrared light, which is just out of the range of human visibility. But infrared wasn't the only form of flare radiation.

"If you were close enough to observe these flares, you'd be in a lot of trouble,"Tana Joseph, an astrophysicist and fellow at the University of Manchester who wasn't involved in the study, told Business Insider in an email. "We would see extremely bright flashes of optical light, and there would be lots of high-energy radiation, like gamma rays and X-rays, that would be very damaging to our bodies."

Peters said flares had been seen coming from Sagittarius A* before. But she added that the new observations, showing the very edge of the black hole, were like going from the resolution of an old television to a high-definition flat-screen TV.

A flashing space-time lens?

black hole veil dead stars illustration nrao alma

What causes these flares is an active mystery.

One idea is that extreme forces around the black hole — primarily intense magnetic fields — will occasionally toss off and accelerate some of the hot plasma into jets, which then bleed off energy as flares.

"We see plasma flares associated with magnetic fields in many places, including our own sun, but we don't yet fully understand the exact causes of such flares,"Misty Bentz, an astrophysicist at Georgia State University who also wasn't part of the study, told Business Insider in an email.

But something far weirder may be at play: large distortions in space-time caused by the spinning of a black hole at some fraction of the speed of light. Such distortions might be focusing the energy bleeding off orbiting blobs of hot plasma into a beam, which occasionally flashes across the telescopes of Earth, creating a flare.

"The black hole is like this lighthouse lens that's causing this thing to flash at us as it goes around," Avery Broderick, an astrophysicist at the Perimeter Institute of Theoretical Physics and the University of Waterloo, told Quanta Magazine. (Broderick first proposed this idea in 2005.)

The ESO's press release says the flares "provide long-awaited confirmation that the object in the center of our galaxy is, as has long been assumed, a supermassive black hole."

This claim is most likely overblown, however, since it's virtually impossible to directly confirm the existence of a black hole, short of visiting one or "listening" to them crash together.

"One might argue that you can never prove the existence of an invisible object like a black hole," Bentz said. "But this new study with Gravity confirms that a compact object with a mass of 4 million suns is still the only way to explain all the observations."

Bentz is eager to know what the flares foretell. She also described the very circular orbit of the blob of plasma as unusual. This may suggest that the rotational axis of Sagittarius A*, like a tilting spinning top, was aligned with the Milky Way a few million years ago but has inexplicably pointed toward Earth.

If true, Bentz said, "that would be quite a puzzle."

SEE ALSO: 8 truly horrifying ways the Earth could die

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NOW WATCH: How our universe will end: 'The black holes will eat up everything'

How cats can survive falling 32 stories high with limited injuries

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  • Cats famously land on their feet when they jump off furniture and trees, but they use a different technique to survive falls from much greater heights.
  • Some cats have walked away from falling as high as 32 stories with limited injuries.
  • Watch the video above to learn the amazing technique cats use to catch their fall.

Following is a transcript of the video.

32 stories above the streets of New York City, a cat fell from a window and lived. After vets treated the cat's chipped tooth and collapsed lungs, the feline was sent home two days later.

Cats fall a lot, and they've gotten really good at it. Drop a cat upside down, for example, and it will almost always land on its feet. That's because cats are extremely flexible. They can twist their bodies mid-air as they fall.

But landing feet first isn't always the best strategy. Like if you're falling from 32 stories up. To figure out how cats manage that perfect landing every time, a series of studies looked at over a 100 cats' falls from two to 32 stories up.

Comes as no surprise that cats who fell from the second floor had fewer injuries than cats who fell from the sixth floor. But here is the fascinating part. Above the seventh story, the extent of the injuries largely stayed the same, no matter how high the cats fell. So, how is that possible?

Well, it all comes down to acrobatics or lack thereof. Cats that fell from two to seven stories up mostly landed feet first. Above that, however, cats used a different technique. Instead of positioning their legs straight down as they fell, they splayed out like a parachuter. And landed belly-first instead.

But this method isn't 100% foolproof. Chest trauma, like a collapsed lung, or broken rib is more common with this landing method. But the risk of breaking a leg is much less. So, how do cats somehow subconsciously know how to land?

It has to do with a physics phenomenon called terminal velocity. At first, the cat plummets faster and faster under gravity until she's fallen the equivalent of five stories. At that point, she hits constant terminal velocity at 100 kilometers per hour. She's now in free fall where air friction counteracts her acceleration under gravity. At this point, she's no longer accelerating and, more importantly, doesn't feel the pull from gravity.

So, here's what researchers think is happening. From two to seven stories up, cats don't have enough time to reach terminal velocity and prep for landing feet first. But once they hit terminal velocity, their instinct changes and they parachute their limbs.

All that said, don't throw your cat out of a window. I can't believe I have to say this. Not only is it still very dangerous, it's not very polite. Don't throw your cat out the window just to see all that go down. Just watch this video again. Just hit the little replay button.

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The worst storms on Earth are nothing compared to the weather on other planets

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  • Earth has some pretty severe weatherhurricanes, earthquakes, and tsunamis can be devastating — but we're better off living here than on other planets. 
  • Earth's worst storms are nothing compared to the sulfuric acid rain on Venus, towering dust devils on Mars, or supersonic winds on Neptune.
  • Watch the video above to see how good we have it here on Earth.

The following is a transcript of the video.

Sulfuric acid raining from the sky. Epic dust storms raging for months on end. And giant hurricanes that could swallow Earth whole. If you think Earth has some bad weather, think again.

Now Mercury has little to no atmosphere, and therefore, no real weather to speak of. But you would feel the full brunt from the most powerful storms in our solar system called coronal mass ejections. These explosive storms form on the Sun and bathe Mercury's surface in high-energy radiation. So if the lack of oxygen and extreme temperatures don't kill you, the radiation certainly will.

This isn't as much of a problem on Venus, however. After all, the entire planet is covered with clouds. Bad news is, they're toxic. These clouds rain sulfuric acid that's so corrosive it would eat through your skin on contact.

On Mars the surface is rocky and desert-like. So wind can stir up loose soil, creating giant dust devils twice the height of Mt. Everest. But that's nothing compared to the dust storms that sometimes engulf the entire planet for months at a time.

And the weather on Jupiter isn't any better. Of course, there's the Great Red Spot. A hurricane-like storm that's been raging for at least 300 years. But there's another storm on Jupiter that's equally powerful. With wind speeds twice as fast as a Category 5 hurricane. Its name is Oval BA. But is commonly called the Little Red Spot. Despite being about the size of Earth. And it's been growing in size since astronomers discovered it in 2000.

Next door, is a weather phenomenon that's even larger: Saturn's north pole harbors a giant jetstream called "The Hexagon." Each of its six distinct sides are larger than Earth itself! And at its center is a massive, rotating cloud system. That's 50 times larger than the average eye of a hurricane on Earth.

Moving right along. Next up: Uranus. If you look at its tilt, you'll notice that Uranus spins on its side! Which makes its seasons more extreme than anywhere else in the solar system. For example, winter time has no sunlight. And because Uranus is so far from the sun, winter lasts the equivalent of 21 Earth years. That's 21 years with temperatures that can reach as low as -216 degrees Celsius.

Last but not least is Neptune. You'll want to pack a windbreaker for this visit. Nicknamed "the windiest planet," Neptune's strongest winds can exceed 1,930 kilometers per hour. That's one and a half times the speed of sound on Earth. And fast enough to fly from NY to LA in just 2.3 hours.

So maybe the acid rain, towering dust devils, and super-fast winds make our planet's weather look a little nicer- not too hot, not too cold, not too windy. Just right.

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Two physicists have developed an equation for the world's perfect pizza

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pizza basil tomatoes

  • While we may have thought that making a decent pizza is all about the ingredients, it's a matter of thermodynamics according to physicists Andrey Varlamov and Andreas Glatz.
  • According to recent research in Physics Education, a thermodynamic equation that you can translate to use at home is the key to perfectly baked pizza.
  • They conducted experiments with Margherita pizzas to produce a formula, and their research was published in the journal, Physics Education.


According to recent research in Physics Education— yes, conducted by a pair of physicists — you don't have to travel all the way to Italy to get a taste of the best pizza.

While making a decent pizza may sound complicated, according to physicists Andrey Varlamov and Andreas Glatz, it's actually quite simple — as the researchers discovered, all you need is a thermodynamic equation.

In conjunction with Italian nutrition expert, Sergio Grasso, the physicists conducted a number of experiments to determine the science behind the perfect pizza, with the findings of their experiments published under the title "The Physics of Baking Good Pizza".

So, what are the factors involved in baking the best pizza?

Normally, the "perfect pizza" will consist of a crispy base, a golden crust, a generous serving of melted cheese, and other fresh toppings — but the most important thing is that the pizza is baked evenly.

The worst case scenario is either a pizza base that's finished cooking before the cheese has even started to melt and the vegetables have cooked through — or a raw, pale, doughy base where your cheese has already caught.

To help cooking amateurs learn to consistently bake the perfect pizza, the researchers experimented with cooking Pizza Margheritas until they found the ideal temperature and time for a pizza to remain in the oven — and have now enshrined their findings in an equation.

Here's how to get the perfect pizza at home

According to the calculation, if a pizza is baked in a traditional brick oven, it will be perfectly cooked in around two minutes if baked at 330 degrees Celsius.

That's actually how pizzas are prepared in restaurants with brick ovens.

So, what's the catch? The issue is that most don't just happen to have a brick oven in their own home — and unless you do, you can't simply apply the same timings and temperatures to an electric oven: in contrast to a brick oven, a metal sheet will transfer heat to your pizza much faster and cook the base and topping at different speeds.

blaze pizza chain 11

According to the study's authors, however, you can still make a really good pizza at home.

The trick is to use the grill function on your oven. First, bake the pizza in the oven as usual until the base is ready.

Once the base is cooked, you can set the temperature to maximum for a few seconds and switch on the grill function. According to the physicists, this will achieve a crispy base, gooey cheese, and well-cooked toppings — all without drying out your pizza.

Even if it doesn't quite count as an authentic, stonebaked pizza, the researchers say it's still pretty delicious in any case.

SEE ALSO: We visited a meat-processing factory to see how McDonald's hamburgers are made

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The December solstice is here. Here's how it works and why it starts winter and summer at the same time.

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earth winter summer solstice december 21 2018 illustration google earth pro

  • The December solstice of 2018 happens on Friday at 5:23 p.m. ET, marking the first day of winter for the Northern Hemisphere.
  • The solstice is known as the winter solstice in the Northern Hemisphere and the summer solstice in the Southern Hemisphere, where it marks the arrival of summer.
  • Solstices mark the shortest and longest days of the year.
  • Earth's tilted axis and its orbit around the sun — not the planet's rotation — are the driving forces behind a solstice.

The December solstice of 2018 happens at 5:23 p.m. ET on Friday.

For people who live in Earth's Northern Hemisphere, it will be the shortest day of the year. It also signals the arrival of winter and a gradual advance toward the spring season, whose beginning is marked by an equinox.

For those in the Southern Hemisphere, it's exactly the opposite: The December solstice marks the start of summer, when days have reached their longest and brightest. This means daylight hours will start to shrink and sunlight will weaken through the March equinox and up until the June solstice.

Two things drive this all-important seasonal shuffle: Earth's tilted axis and the planet's orbit around the sun.

How the December solstice works

Earth orbits the sun once every 365 days and six hours and rotates once a day on a tilted axis.

That tilt is about 23.45 degrees (for now), and it bathes different parts of the world with various intensities of light over the course of a year. Meanwhile, Earth's rotation keeps the sun's heat even, sort of like a 7,917-mile-wide rotisserie chicken made of rock and a little water.

Read more: The darkest day of the year is here — here are some science-backed ways to fight winter blues

From the view on the ground in the Northern Hemisphere, the December solstice is when the sun's high point in the sky, called a zenith, reaches its minimum or low point close to the horizon. From space, it's when the sun's most direct rays creep the farthest south, to a line called the Tropic of Capricorn:

earth during december solstice summer winter tropic cancer capricorn tilt axis sunlight graphic insider shayanne gal

If you stand on the Tropic of Capricorn at midday on Friday, the sun will appear more or less directly overhead. Your shadow will also be at its absolute minimum. (Solstice literally means "sun-stopping," according to TimeAndDate.com.)

The length of daylight will be at its longest in the Southern Hemisphere too. This gets more extreme the farther south you go from the equator, since there's more of Earth's atmosphere to refract sunlight the farther you are from the equator.

But this moment won't last, since the Earth makes its way around the sun at a speed of roughly 66,600 mph.

How Earth's axis and orbit drive the seasons

Our planet's orbit is elliptical, and its center of gravity is slightly offset from the sun.

This means the time it takes to cycle through the seasons isn't perfectly divvied up:

earth equinoxes solstices sun light axial tilt seasons diagram graphics insider shayanne gal

As the graphic above shows, it takes 89 days after the December solstice for Earth to reach the March equinox — that's when the most direct rays of the sun have slipped back up to the equator. Another 92 days and 19 hours later, it will be the June solstice. At that point, the sun's most direct rays reach the Tropic of Cancer, summer starts for the Northern Hemisphere, and winter begins for those south of the equator.

Then it takes 93 days and 14 hours for the sun's zenith to get back to the equator and kick off the September equinox, followed by 89 days and 19 hours to complete the cycle with the December solstice.

During each of these phases, certain regions of Earth's surface get more sunlight, and energy gets stored or sapped from water sources, leading to the creation of seasonal temperatures and weather variations.

What the seasons look like from space

Some satellites fly in a geosynchronous orbit, which means they orbit the Earth and move fast enough to hover above one spot on the planet.

This creates a great opportunity to photograph the Earth over the course of the year and see how the angle of sun changes.

NASA's Goddard Space Flight Center created the animation below using geosynchronous-satellite images taken over Africa, and it clearly shows the seasonal progression.

This story was adapted from a similar post about the June solstice.

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There is a 'dark side' of the moon, but you are probably using the term incorrectly all of the time

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earth rise moon lunar far side craters simulation nasa science visualization studio svs 00003

  • People often say "dark side" of the moon when referring to the lunar face we can't see from Earth.
  • This common use of the phrase is wrong— the term scientists use is the "far side."
  • One lunar side always faces Earth, or is tidally locked, because the moon's rotation and orbit is closely synced-up with our planet's.
  • The moon spins about its axis and orbits the sun with Earth, so its night or "dark" side is constantly moving.

The English rock band Pink Floyd named a best-selling album after it. There are Disney anthems that sing it. Even news stories (including some of our own) plaster it across headlines: the "dark side of the moon."

However, the phrase is almost always used incorrectly.

When people say the "dark side" of the moon, they're most often referring to what is technically called the "far side"— where China just landed its Chang'e 4 spacecraft for the first time in history. Scientists call the face of the moon that we always see the "near side."

The reason why the far side exists is owed to complex physics called tidal locking, and the origin of how Luna got stuck dates all the way back to the formation of the moon-Earth system.

Today, the net result is that the moon spins counterclockwise on its axis, and the moon also orbits Earth in a counterclockwise fashion, and it does so almost perfectly in sync.

On average, according to Wolfram Alpha (a search engine for nerds), one lunar rotation takes 27 days, 7 hours, 43 minutes, and 40 seconds. This is exactly the same amount of time it takes the moon to orbit our planet. If the moon did not rotate on its axis, we'd see the full far side about once every 30 days.

That's not to say there is no such thing as the moon's dark side, though you'd have to accept that it's always moving.

far dark side moon lighting day night visualization nasa gsfc svs s3m 1920

It works out that the average length of a month lasts about 29 days, 12 hours, 44 minutes, and 2.8 seconds, per Wolfram Alpha. This time span is a couple of days longer than the moon's sidereal day, or time it takes to rotate once, because the moon-Earth system orbits the sun.

This celestial dance and the angle of sunlight makes the average lunar night last for about 14 days, 18 hours, 22 minutes, and 1 second at any given point on the moon.

Put another way: The dark side of the moon is the half not illuminated by the sun, and it's constantly creeping around the world, just as it happens on Earth. Except instead of taking about 24 hours to complete one lap, the dark phase takes about 30 days.

Here's a sped-up view of that process as seen from the moon's far side in an animation created by NASA's Science Visualization Studio:

We see a new moon when the dark side faces Earth, and a full moon when the dark side covers the far side. So if you want to shout "China is on the dark side of the moon!" into the night sky and be absolutely correct, you will have to wait until January 21 at 12:16 a.m. ET— the moment that the next full moon peaks.

The event also happens to be what's called a "super blood wolf moon," so be sure to mark your calendar to see it.

SEE ALSO: 'This is more than just a landing': Why China's mission at the far side of the moon should be a wake-up call for the world

DON'T MISS: Each year the government asks 10 simple questions to test the public's knowledge of science. Can you correctly answer them all?

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NOW WATCH: China just made history by being the first to ever land on the far side of the moon

A city in China wants to launch an artificial moon into orbit by 2020 — here's what would happen if Earth really did have two moons

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  • A city in China wants to launch an artificial moon into orbit by 2020. 
  • China's moon would be far less massive than our current moon, but their ambitious idea made us wonder what would happen if Earth had a second moon that was the same mass as our current moon.
  • If this happened, it would cause sea levels to rise, flooding coastal cities like New York and Singapore.
  • The extra pull of the moons would also slow down the Earth's rotation, causing the day to get longer.

A city in China wants to launch an artificial moon into orbit by 2020 as a way to reduce energy needs by replacing street light with artificial moonlight. Regardless of whether or not they succeed, their ambitious idea really made us wonder…

What would happen if Earth had two moons?

Well, it wouldn't be pretty.

Imagine the Moon's identical twin comes hurtling by and is trapped by Earth's gravity. As it settles into orbit, halfway between Earth and our original moon, it yanks violently at the oceans. In the real world, this is how our original Moon helps generate tides. So, the second moon would amplify the effect. Causing peak tides that would be 6 times higher, eroding shorelines and flooding many of our world's greatest cities including: New York, Singapore, and London — gone.

But not all destruction would happen on Earth. The combined pull of the planet and the original moon would also yank on the second moon. The second moon would be caught in a tug of war between Earth and the original moon. The gravitational pull back and forth from both ends would warp the second moon's surface triggering tremendous volcanic activity. Flooding the second moon's surface with red-hot rivers of lava. Just like hundreds of the volcanoes you see today on Jupiter's hellish moon, Io.

But even that's not the end of the spectacle. Right now, our current moon is spiraling away from Earth at 3.8 cm a year. That's about how fast your fingernails grow. At the same time, it pulls on the Earth slowing down the planet's rotation. Which is actually lengthening our days by around 1 second every 40,000 years. It may not sound like much, but with two moons in place it would accelerate this process even more.

Millions of years from now, the day will have grown by 16%! Lasting longer than 28 hours! Now, a little extra time in the day may sound pretty nice, but here's the problem: the extra moon would drift towards the current Moon.

And that's where the real danger comes in.

After millions of years, the two moons would collide! The impact would be so massive it would rip the very core of the moons apart. Lava would erupt from their center — like a runny egg in space. Casting a vivid red light in the sky on Earth. Meanwhile, debris would go hurtling in all directions, where some of it would inevitably strike Earth, forming massive craters miles wide.

It would be an apocalypse for all life on Earth.

And what didn't hit the planet would instead be trapped by Earth's gravity. Forming a ring of debris around the equator. Similar to the rings around Saturn — but not for long. Within just a few years, those chunks would clump together, forming one large, single body.

Perhaps any life that survived will call it the Moon, or maybe something even better.

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NASA's deep-space nuclear-power crisis may soon end, thanks to a clever new robot in Tennessee

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  • NASA relies on plutonium-238, a human-made radioactive element, to power its longest-operating and farthest-flying spacecraft.
  • Nearly all Pu-238 was made during the Cold War, and supplies are running low. The shortage threatens to limit deep-space exploration.
  • The Department of Energy is now making new Pu-238 and recently achieved an eightfold increase in production with a new robot.
  • Oak Ridge National Laboratory in Tennessee says its robot is "the next key step" in making enough plutonium to perpetually meet the needs of NASA.

The US government says a new robot is poised to help it create a reliable, long-term supply chain of plutonium-238, a radioactive material NASA requires to explore deep space.

NASA uses Pu-238 to power its most epic space missions— among them New Horizons (now beyond Pluto), the Voyagers (now in interstellar space), and Cassini (now part of Saturn).

As Pu-238 radioactively decays and generates heat, devices called radioisotope power sources convert some of that energy into electricity. Because Pu-238 takes centuries to cool down, the contraptions can keep a robot humming for decades.

cassini radioisotope power source rps nuclear battery plutonium 238 nasa jpl 7513_97pc1536But Pu-238 is human-made and one of the rarest and most valuable materials on Earth. In fact, the last time anyone manufactured it in earnest was during Cold War-era nuclear-weapons production. Today, NASA has perhaps three missions' worth of the stuff left before the supply runs out.

NASA tried to address the shrinking of its supply in the 1990s, but the agency and its partners didn't secure funding to create a new pipeline for Pu-238 until 2012.

That work, which gets about $20 million in funding per year, is finally starting to move from the research phase toward full-scale production. The Department of Energy hopes to meet the NASA-mandated need of 3.3 pounds (1,500 grams) per year by 2025.

Oak Ridge National Laboratory in Tennessee, which is leading the work, says it recently proved there is a way to produce eight times as much Pu-238 as it made just a couple of years ago, thanks to a new automated robot.

"You can't go to Walmart and buy something that will do this," Bob Wham, the Pu-238 supply program manager at Oak Ridge, told Business Insider.

A new recipe for Pu-238 is born

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Oak Ridge made the first plutonium for NASA in decades in December 2015. It was a small amount — just 1.8 ounces, or 50 grams — but it was tangible proof the lab had created a recipe and the tools to get the job done.

"That was a huge accomplishment, but just a first big step," Jason Ellis, a representative for Oak Ridge, told Business Insider.

This week, the lab said in a press release that it was ready to push annual production to more than 14 ounces a year, an eightfold increase.

"This is another big accomplishment and a huge step because we're going to a production scale," Ellis said. "It's a more efficient process. ... It's that next key step."

The old recipe for Pu-238 doesn't work anymore, Wham said, because "nobody has the huge production reactors that were in use during the Cold War." So he and his colleagues had to come up with a modern, safer recipe.

plutonium pu 238 production neptunium pellet green laser scanning nuclear hot cell oak ridge national laboratory ornl department energy doe

He said a batch of Pu-238 takes about 28 to 36 months to make from start to finish, and the process requires a starting material called neptunium-237.

The Np-237 is pressed into small pellets, slipped inside an aluminum sleeve, and inserted into a special nuclear reactor at Oak Ridge called the High Flux Isotope Reactor. After a few months of bathing in a stream of neutrons from the reactor's core, some of the Np-237 is transmuted into Pu-238. (Pu-238 is not used in nuclear-weapons cores, though its sister radioisotope plutonium-239 is.)

After the targets cool off in a pool of water for many months, workers dissolve them in acid, chemically separate the plutonium and neptunium, and refine both materials. The purified plutonium is set aside for NASA, and the purified neptunium is put back into more targets.

But the neptunium poses a risk to human workers: A small fraction decays into a very radioactive substance called protactinium-233. Half of this radioisotope decays every 27 days, releasing powerful gamma rays in the process.

"A tiny bit of that protactinium can go a long way to delivering a lot of dose to workers," Wham said.

This radioactive exposure limits the amount of time a trained worker can make the Np-237 targets for reactors, and Wham has only a few workers to use.

What's more, full-scale production of Pu-238 for NASA will require making perhaps 20,000 to 25,000 pellets per year. Wham also said the tedious, repetitive process must be done through a protective working unit called a hot cell.

"It would drive me nuts to have to press 20,000 pellets in a year," he said. "It'd drive me cross-eyed crazy."

Heating up production for NASA

To create more than a couple of ounces per year, Wham and his team worked with others in the Energy Department to create an automated machine that fits inside a hot cell.

They made two, just in case.

"We don't necessarily need it, but it's a good idea for redundancy," Wham said. "If we have a problem or something fails with the mainline machine, it won't take forever to catch back up."

The robot has a multipurpose arm designed to do repetitive work more quickly and safely than human workers. It picks up a funnel, carries it to a die, pours in a premeasured amount of Np-237 and aluminum, presses the pellet, and loads it into a tray. Workers then pack the pellets into tubes that are inserted into the reactor.

plutonium pu 238 production aluminum tube sleeve robotic arm neptunium pellet nuclear hot cell oak ridge national laboratory ornl department energy doe

Wham's team will have to kick up production about another fourfold to meet its NASA-mandated goal. But he said he's confident the project is on the right path, adding that the pipeline is not working at its fastest — he wants to ensure every step of the process is well-understood before scaling it up.

"There are a lot of requirements to manage a radioactive material and do so in a safe manner," Wham said.

Once Oak Ridge is ready to scale production, it will have help from Idaho National Laboratory across the country. That lab has a facility called the Advanced Test Reactor that is also capable of forging Np-237 into Pu-238.

Read more: NASA could run out of nuclear fuel for deep-space missions within a decade

Wham said he thinks that if push came to shove, the Department of Energy could crank out about 11 pounds of Pu-238 per year — more than three times the amount it's been asked to make.

"I think we could go larger to meet a higher demand for NASA, if they asked for it," Wham added. "Right now we're fitting in to what they believe their cadence is for nuclear-enabled missions."

SEE ALSO: The 15 most incredible plutonium-powered space missions of all time

DON'T MISS: A forgotten war technology could safely power Earth for millions of years. Here's why we aren't using it.

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NOW WATCH: China made an artificial star that's 6 times as hot as the sun, and it could be the future of energy

The speed of light is torturously slow, and these 3 simple animations by a scientist at NASA prove it

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  • The speed of light in a vacuum is about 186,282 miles per second (299,792 kilometers per second).
  • A scientist at NASA animated how long it takes light to travel around Earth, as well as between the planet, its moon, and Mars.
  • The physics animations show just how fast (and slow) the speed limit of the universe can be.

A series of new animations by a NASA scientist show just how zippy — and also how torturously slow — the speed of light can be.

Light speed is the fastest that any material object can travel through space. That is, of course, barring the existence of theoretical shortcuts in the fabric of space called wormholes (and the ability to go through them without being destroyed).

In a perfectly empty vacuum, a particle of light, which is called a photon, can travel 186,282 miles per second (299,792 kilometers per second), or about 670.6 million mph (1.079 billion kilometers per hour).

This is incredibly fast. However, light speed can be frustratingly slow if you're trying to communicate with or reach other planets, especially any worlds beyond our solar system.

Read more: Astronomers found a 'cold super-Earth' less than 6 light-years away — and it may be the first rocky planet we'll photograph beyond the solar system

To depict the speed limit of the cosmos in a way anyone could understand, James O'Donoghue, a planetary scientist at NASA's Goddard Space Flight Center, took it upon himself to animate it.

"My animations were made to show as instantly as possible the whole context of what I'm trying to convey," O'Donoghue told Business Insider via Twitter. "When I revised for my exams, I used to draw complex concepts out by hand just to truly understand, so that's what I'm doing here."

O'Donoghue said he only recently learned how to create these animations — his first were for a NASA news release about Saturn's vanishing rings. After that, he moved on to animating other difficult-to-grasp space concepts, including a video illustrating the rotation speeds and sizes of the planets. He said that one "garnered millions of views" when he posted it on Twitter.

O'Donoghue's latest effort looks at three different light-speed scenarios to convey how fast (and how painfully slow) photons can be.

How fast light travels relative to Earth

One of O'Donoghue's first animations shows how fast light moves in relation to Earth.

Earth is 24,901 miles around at its center. If our world had no atmosphere (air refracts and slows down light a little bit), a photon skimming along its surface could lap the equator nearly 7.5 times every second.

In this depiction, the speed of light seems pretty fast — though the movie also shows how finite it is.

How fast light travels between Earth and the moon

A second animation by O'Donoghue takes a big step back from Earth to include the moon.

On average, there is about 238,855 miles (384,400 kilometers) of distance between our planet and its large natural satellite.

This means all moonlight we see is 1.255 seconds old, and a round-trip between the Earth and moon at light speed takes about 2.51 seconds.

This timing is growing every day, however, as the moon is drifting farther from Earth at a rate of about 1.5 inches (3.8 centimeters) per year. (The moon is constantly sapping Earth's rotational energy via ocean tides, boosting its orbit to a greater and greater distance.)

How fast light travels between Earth and Mars

O'Donoghue's third speed-of-light animation illustrates the challenge that many planetary scientists deal with on a daily basis.

When NASA tries to talk to or download data from a spacecraft, such as the InSight probe on Mars, it can do so only at the speed of light. This is much too slow to operate a spacecraft in "live mode" as you would a remote-controlled car. So, commands must be carefully thought out, prepackaged, and aimed at the precise location in space at the precise time so that they don't miss their target.

Read more: NASA can hear the 'haunting' sound of dust devils tearing across Mars with its new $830 million lander

The fastest a conversation could ever happen between Earth and Mars is when the planets are at their nearest point to one another, an event called closest approach that happens once roughly every two years. On average, that best-case-scenario distance is about 33.9 million miles (54.6 million kilometers).

As that 60-second clip of O'Donoghue's full movie on YouTube shows, light takes 3 minutes 2 seconds to travel between Earth and Mars at closest approach. That's six minutes and four seconds for a light-speed round-trip.

But on average, Mars is about 158 million miles from Earth — so the average round-trip communication takes about 28 minutes and 12 seconds.

The speed of light gets more depressing the farther you go

starshot spacecraft light sail laser beam earth space alpha centauri breakthrough foundation

The hurdle of light's finite speed gets even more challenging for spacecraft such as New Horizons, which is now more than 4 billion miles from Earth, and the Voyager 1 and 2 spacecraft, each of which have reached the space between stars.

The situation gets downright depressing when you start looking outside the solar system. The closest-known exoplanet, called Proxima b, is about 4.2 light-years away from us (a distance of about 24.7 trillion miles or 39.7 trillion kilometers).

However, the fastest any spacecraft has ever gone is NASA's Parker Solar Probe at about 213,200 mph; at that speed, it'd take 13,211 years to reach Proxima b.

A Russian-American billionaire's Breakthrough Starshot project envisions a way to address this speed problem. The multidecade plan is to build and fly tiny "nanocraft" past such exoplanets via ultrapowerful laser blasts, ideally at a planned cruise velocity of 20% of the speed of light. Yet the entire concept is still theoretical, may end up not working, and would operate at a fraction of light-speed.

Space is impossibly vast. Although the universe is about 13.77 billion years old, its edge is about 45.34 billion light-years away in any direction and is increasing due to expansion.

That's far too big to illustrate in a simple animation. One illustration comes close, though: this image created by musician Pablo Carlos Budassi, which combines logarithmic maps of the universe from Princeton and images from NASA to capture it all in one picture.

This story has been updated.

SEE ALSO: 17 'facts' about space and Earth that you thought were true — but have been debunked by science

DON'T MISS: There is a 'dark side' of the moon, but you are probably using the term incorrectly all of the time

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NOW WATCH: Albert Einstein has a famous loophole in the special theory of relativity that could predict faster-than-light travel

The world's oldest Nobel Prize winner, a 96-year-old physicist, says his new invention will give everyone in the world clean, cheap energy

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  • At 96, Arthur Ashkin is the oldest person to ever be awarded a Nobel Prize.
  • Ashkin won half the 2018 prize in physics for his role in developing technology that makes very small beings "levitate" using only light. He did that work at Bell Labs in the 1960s, '70s, and '80s.
  • His discovery spurred the invention of optical tweezers, which have been used to stretch DNA and invent a life-saving malaria test, among other medical uses.
  • The Nobel laureate says he's not done inventing yet: His lifelong obsession with light has taken a recent turn toward solar energy.

RUMSON, New Jersey — Arthur Ashkin, the world's oldest Nobel Prize winner, favors comfort over style.

When I met him in his New Jersey home, he was sporting a fleece-lined zip-up, corduroy pants, and fuzz-lined Crocs.

The outfit makes sense for someone who spends a lot of time tinkering with new inventions in the basement.

Ashkin, who's 96 years old, has turned the bottom floor of his house into a kind of laboratory where he's developing a solar-energy-harnessing device.

"I'm making cheap electricity," he said.

Ashkin's new invention uses geometry to capture and funnel light. It relies on reflective concentrator tubes that intensify solar reflections, which could make existing solar panels more efficient or perhaps replace them with something cheaper and simpler.

The tubes are "dirt cheap," Ashkin says — costing pennies to create — which is why he thinks they "will save the world."

He's even got his eye on a second Nobel Prize.

"And I'm gonna win too," he said.

Ashkin's lifelong fascination with light has already saved countless lives. He shared the 2018 Nobel Prize in physics for his role in inventing a tiny object-levitating technology called optical tweezers, a powerful laser beam that can "catch very small things," as Ashkin describes it.

Optical tweezers can hold and stretch DNA, helping us probe some of the biggest mysteries of life.

The technique has been used in biology, nanotechnology, spectroscopy and more; it has helped researchers develop a malaria blood test and better understand how cholesterol-lowering drugs soften our red blood cells.

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But Ashkin is not interested in many Nobel celebrations. He's already focused on his forthcoming light "concentrators."

How to levitate

When Ashkin got his fateful call from Stockholm's Royal Swedish Academy of Sciences, on October 2, he thought it was a scam.

That's because another scientist, former US Secretary of Energy Stephen Chu, had already shared the 1997 Nobel for some related research at Bell Labs, which was where Ashkin had worked when he developed the optical tweezers.

Chu's work built on Ashkin's, which had involved gathering pond scum, plopping the wiggly organisms under a microscope, and making them "levitate," as Ashkin describes it, using only a laser beam.

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"This light is shining on you. Do you know that it's pushing you?" he asked me, pointing to a nearby lamp. "Most people don't. But it is, because it's got energy. The only thing is, it's so small you don't feel it."

Ashkin started researching these properties of light to improve communications technology for Bell.

"Light is a wave, right?" he said. "In physics, it's also a particle ... and it's sort of a mysterious particle."

But once Ashkin realized that pressure from photons, the fundamental particles of light, could pick up very small objects, he pivoted to focus on biology and started using optical tweezers to trap, lift, pull, and stretch things as small as DNA.

Bell Labs gave Ashkin license to explore the ways this technique might apply to living beings, and he figured out how to hold single-celled organisms hostage using light.

"You can tweeze them just like you would with tweezers," the current Nokia Bell Labs president, Marcus Weldon, said "[Ashkin] could move nuclei around themselves, and they could do all these cool things."

Some of Ashkin's Bell Labs colleagues were dumbfounded when he caught critters in the light for the first time, he recalled.

"'Oh, you got to see this — Ashkin's trapping bugs! He's trapping bugs!'" he remembers someone shouting.

"It surprised me. It would surprise anybody," Ashkin said. "I invented optical levitation."

But Ashkin doesn't linger much on those moments much anymore. After he realized that early-morning Nobel Prize call was real, he was mostly excited about the prospect that his popularity might help get his latest research published.

ashkin at his Bell microscope.JPG

Concentrating light

When Ashkin retired from Bell Labs, in 1992, the labs gave him his levitation equipment to take home. He took everything but the all-important high-powered laser. His house doesn't have the voltage to run it.

In his basement, Ashkin now works with his curved spine hunched over a workbench. The cane he uses to walk around upstairs is cast aside and forgotten. Rolls of masking tape and silver reflective paper litter the wooden worktables and concrete floor. He has built so many shiny, light-bending contraptions in this basement lab that some are overflowing into his garage, leaving barely enough room for the family car.

Ashkin has already filed the necessary patent paperwork (he holds at least 47 patents to date) for his new invention, but said he isn't ready to share photos of the concentrators with the public just yet.

Soon, he hopes to publish his results in the journal Science.

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He's confident that once the design is released, the new technology will ricochet around the world, from his home in New Jersey to India and beyond, providing inexpensive, clean, renewable power to homes and businesses.

"Great intellects generally don't rest," Weldon said. "It's clear that he is still questing to solve great problems despite his Nobel success. And I love that."

Ashkin says he'll use the Nobel money to buy his wife a 'good meal'

Ashkin grew up in Brooklyn, New York, during the Great Depression, a bony rail of a kid who was a picky eater and subsisted mostly on milk. His father, a dentist, emigrated from Ukraine. The only book he remembers the family owning was "The Book of Knowledge: The Children's Encyclopedia (That Leads to Love of Learning)."

Ashkin devoured the tome — especially the sections that featured a character named "Wonder Why."

"Wonder Why would say, 'Why is the sky blue?'" Ashkin recalled. "Then Wonder Why would tell you. I was fascinated, because I wanted to know how things worked ... that was my introduction to science."

That curiosity eventually led Ashkin to get his doctorate at Cornell. There he met a woman named Aline, who would become his wife of 64 years.

"I was very shy, but I knew that this lady was special," Ashkin said. "So I had enough nerve to ask for her phone number."

Ashkin asserts that he never took a chemistry class because he learned everything he needed to know about it from his wife, a chemistry whiz 10 years his junior.

"I married her because she is smart!" he said. The feeling is mutual.

"I really am surprised that at the age of 96 he is so much with it and so brilliant," Aline said, though she added: "He's a little bit cranky now, at times."

The Nobel laureate agreed: "I can be cranky," Ashkin said.

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When asked how he'll use his prize money — which amounts to almost $500,000 — Ashkin said he's got one idea in mind.

"I want to take Aline to a good restaurant, and we'll have a good meal," he said. His wife said there are five grandchildren going to college soon who could probably use a good chunk of that money too.

While Ashkin is looking forward to revealing his next invention to the world, his wife doesn't see any reason to wait for a second prize to celebrate.

"I think one is enough," she said.

SEE ALSO: Bill Gates says investing in 4 simple plans has saved millions of lives and provided a better return on investment than the stock market

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NOW WATCH: Saturn is officially losing its rings — and they're disappearing much faster than scientists had anticipated

A 'ridiculous' yet simple animation by a NASA scientist shows how long it takes light to reach Pluto. If you plan to watch it, take a day off work.

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  • The speed of light is about 186,282 miles per second (299,792 kilometers per second) in a vacuum.
  • That can be tough to comprehend, so a scientist at NASA created several simple animations to demonstrate light's speed.
  • His latest video — which he described as "ridiculous"—shows how long it takes light to go from the sun to Pluto in real time.
  • You'd need most of your working hours to watch the entire movie.

The speed of light is not as fast as you might think.

To underscore this point, a researcher at NASA created a simple new animation (below) that shows what light-speed travel looks like between from the sun to Pluto.

James O'Donoghue, a planetary scientist at the Goddard Space Flight Center, said he learned how to make animations only in the past few months. For practice and for fun, he created simple movies that show photons (particles of light) zipping around Earth, bouncing between our planet and the moon, and even traveling to Mars.

"My animations were made to show as instantly as possible the whole context of what I'm trying to convey," O'Donoghue previously told Business Insider. "When I revised for my exams, I used to draw complex concepts out by hand just to truly understand, so that's what I'm doing here."

The animations have been viewed millions of times.

Read more: A startup is developing a 100-gigawatt laser to propel a probe to another star system. That may be powerful enough to 'ignite an entire city.'

In a perfectly empty vacuum, a photon can travel 186,282 miles per second (299,792 kilometers per second), or about 670.6 million mph (1.079 billion kilometers per hour).

Earlier this week, O'Donoghue uploaded a video of photons leaving the sun and traveling all the way to Pluto, which is about 3 billion miles away.

He described his new film as "quite ridiculous" in a message to Business Insider, since it lasts a whopping 5 hours, 28 minutes, and 20 seconds.

"The aim of my outreach is to simply to convey distances, sizes (scales) to people, and I think most people would be curious how far Pluto is," O'Donoghue tweeted on Thursday, adding: "If people don't like Pluto in this, they can put their finger over it."

Below is the full animation. You'd have to take a day off work or school to watch it in its entirety.

You can watch O'Donoghue's other (much shorter) light-speed animations here.

SEE ALSO: 17 'facts' about space and Earth that you thought were true — but have been debunked by science

DON'T MISS: There is a 'dark side' of the moon, but you are probably using the term incorrectly all of the time

Join the conversation about this story »

NOW WATCH: Albert Einstein has a famous loophole in the special theory of relativity that could predict faster-than-light travel

Elon Musk says SpaceX is developing a 'bleeding' heavy-metal rocket ship. Making it work may be 100 times as hard as NASA's most difficult Mars mission, one expert says.

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  • SpaceX is developing a giant, fully reusable launch system called Starship to ferry people to and from Mars.
  • Elon Musk, the aerospace company's founder, said he recently made "radical" changes to the spacecraft's design.
  • One change gives Starship a stainless-steel body. The other is a heat shield that will "bleed" liquid during landing to cool off the spaceship and prevent it from burning up.
  • But aerospace experts anticipate huge challenges for Starship, including clogs in heat-shield pores that could destroy the spacecraft.
  • A chief engineer at NASA said landing Starship full of people on Mars may be about 100 times as difficult as the hardest thing the agency has ever done at the red planet.

SpaceX, the aerospace company founded by Elon Musk, is working diligently on a wildly ambitious project: to permanently settle people on Mars.

To help make that vision a reality, Musk's company is developing a colossal, fully reusable launch system called Starship.

Starship is envisioned as a 180-foot-tall spaceship that will ride into orbit atop Super Heavy, a rocket booster about 220 feet tall, according to Musk's latest descriptions. The spaceship is designed to be refueled in low-Earth orbit in order to propel 100 passengers and more than 100 tons of cargo at a time to Mars.

But the success or failure of the launch system — and by extension Musk's plan to back up the human race — may boil down to the viability of two major and recent design changes, which Musk has described as "radical" and "delightfully counterintuitive."

One change involves building the spaceship from stainless-steel alloys instead of carbon-fiber composites. But the most surprising shift, according to aerospace-industry experts, is the way Starship will try to keep itself from burning up in the atmospheres of Mars and Earth.

Instead of relying on of thousands of heavy ceramic tiles to shield Starship from heat, as NASA did with its space shuttle, Musk says the spaceship will "bleed" rocket fuel through tiny pores to cool itself down. In theory, putting liquid between Starship's steel skin and the scorching-hot plasma generated while it plows through atmospheric gases would prevent the ship's destruction.

Read more: Astronaut Chris Hadfield says we could have gone to Mars decades ago — here's why we haven't

But whether SpaceX can pull off a launch system of this unprecedented size and design remains to be seen, says Walt Engelund, an aerospace engineer and the director of the Space Technology and Exploration Directorate at NASA Langley.

"Large-scale entry, descent, and landing is something that NASA has been challenged by for decades. We've spent a lot of time and given a lot of thought to how we might do it at Mars," Engelund told Business Insider. "We've landed the metric-ton Curiosity rover — that's the biggest thing we've ever put down on the surface of Mars."

To go from the Martian landing of a car-size robot to a building-size ship filled with humans, Engelund said, is "a couple orders of magnitude"— roughly 100 times — more difficult than the Curiosity landing, which he said "is arguably one of the hardest things we've ever done at NASA."

"It won't be easy for us or SpaceX," Engelund said.

Why Starship turned into a heavy-metal rocket ship

Musk thinks he can build a self-sufficient city on the red planet by 2050. He wants individual tickets to Mars to be as cheap as a house on Earth, and for return trips to be free.

The Starship–Super Heavy launch system is the way Musk plans to achieve that goal, and he said the switch to stainless-steel alloys is a way to keep costs down and build the system more quickly.

"Starship will look like liquid silver," Musk said of the change in December, adding that the ship will have a mirror-polish finish to help reflect heat — a literal case of cool factor.

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In an interview with Popular Mechanics, Musk explained that steel is about 67 times as cheap by weight as the lightweight yet superstrong carbon-fiber composites that SpaceX had planned to use as late as September. Steel is also easier to work with than carbon fiber, allows for faster prototyping, and stands up better to intense heat.

What's more, Musk said, steel's strength is "boosted by 50%" when it touches ultracold liquids, including the cryogenic methane and oxygen that Starship might use to propel itself through space.

Read more: SpaceX test-fired a Raptor rocket engine with 'insane power' for moon and Mars missions. The future of Musk's company may ride on its unrivaled performance.

The problem with steel, though, is that the material is dense and heavy. At least one early version of General Dynamics' Atlas missile, which was made from the metal, crumpled under its own weight on a launchpad.

Yet Musk has suggested that SpaceX's use of steel is much different and will make the redesigned Starship stronger, more durable, and less heavy. Ultimately, he said, the material change will improve the rocket ship's performance over the old design.

"I'm confident that a stainless steel ship will be lighter than advanced aluminum or carbon fiber, because of strength to weight vs temperature & reduced need for heat shielding," Musk tweeted in January.

But as tough as steel is, it's not invincible, especially when it forms the skin of a spacecraft screaming through atmospheric gases.

Sweating and bleeding for survival

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Starship could enter through Mars' and Earth's atmospheres at 19,000 mph. At such speeds, Musk said, parts of the ship's underbelly, such as its nose, could be exposed to temperatures of about 2,700 degrees Fahrenheit.

That's enough heat to destroy the steel alloy that Musk said SpaceX might use for Starship's outer skin. Called 310S, the material is often billed as a heat-resistant metal, since it has a lot of chromium and nickel blended into it. (It's not unlike the steel used in kitchen pots and pans.) But 310S steel nonetheless starts to react with oxygen and corrode at about 2,000 degrees and melts at about 2,400.

The rocket ship needs protection from the intense heat, which is why Musk's plans call for Starship's body to cool itself using liquid fuel during landing.

Musk told Popular Mechanics that he decided to forgo space-shuttle-like thermal tiles to save weight and avoid the risk that a damaged or lost tile could compromise a heat shield.

Read more: This veteran NASA astronaut has tried SpaceX and Boeing's new spaceships — here's what she thinks

Instead, he explained, Starship would "bleed" or sweat rocket fuel from tiny holes in its steel skin, and that liquid layer would carry away the scorching heat of atmospheric entry.

"On the windward side, what I want to do is have the first-ever regenerative heat shield. A double-walled stainless shell — like a stainless-steel sandwich," Musk said. "You flow either fuel or water in between the sandwich layer, and then you have micro-perforations on the outside — very tiny perforations — and you essentially bleed water, or you could bleed fuel, through the micro-perforations on the outside. You wouldn't see them unless you got up close."

He added that the heat shield would do double duty by strengthening Starship's steel body.

"To the best of my knowledge, this has never been proposed before," Musk said.

Experts told Business Insider that Musk is correct that no spaceship has ever launched into orbit and returned to Earth using such a heat shield. But the concept of sweating or "transpirational" thermal protection is not novel, and it has a history of being an incredibly tricky engineering challenge.

Transpirational cooling for moon men and ICBMs

spacex starship super heavy stainless steel rocket booster spaceship illustration copyright of kimi talvitie 2

Transpirational or "active" cooling has been around for millions of years in the form of mammalian skin. When human body temperatures rise too high, for instance, microscopic pores push out sweat. This liquid then evaporates to carry away excess warmth and prevent overheating.

As far as sweating spacecraft are concerned, NASA began toying with the nature-inspired cooling system before landing astronauts on the moon.

"The idea of transpirational cooling is not new. That's been around for decades," Engelund said.

One patent filed by NASA in 1965 suggested using astronaut urine to cool down a heat shield on the bottom of a space capsule. As late as 2006, the space agency spent at least $70,000 on research into an inflatable, transpiration-cooled heat shield that could help land spacecraft on Mars.

"Sweating" spacecraft also played a role in the Cold War arms race. In March 1976, the US Department of Defense test-launched a transpiration-cooled nose tip for reentry vehicles. Such reentry vehicles are made to fly into space atop intercontinental ballistic missiles, reenter Earth's atmosphere at thousands of miles per hour, and strike distant targets with nuclear warheads.

But according to US Air Force historical documents, the project was canceled later in the 1970s because of limited funding and "design problems that had plagued the development effort." Engineers instead opted for simpler "ablative" heat shields that insulate a vehicle by burning away during reentry.

Information about the problems in defense-related transpirational heat shields is mostly classified. But George Herbert, an aerospace engineer who's researched military uses of space-launch vehicles, told Business Insider in an email that "issues reported and known include blocked transpiration holes."

In other words, a challenge commonly faced by teenage skin: clogged pores.

'What if a bird poops on your rocket?'

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Several experts told Business Insider they were concerned about the problem of blockage in Starship's heat-shield design.

"You can imagine it wouldn't take much to clog something like that, if they were microscopic pores," Engelund said.

Dwayne Day, who helped investigate the loss of NASA's Columbia space shuttle and its crew, imagined one annoyingly common scenario that the Starship would face at any launch site on Earth.

"What if a bird poops on your rocket and it plugs up a few holes, and then when the thing is returning, no coolant comes out of those holes and that section of the vehicle overheats?" Day wrote in an email to Business Insider.

Engelund said he's seen issues with clogged coolant systems in tests performed inside NASA's hypersonic wind tunnels. During such experiments, scale models of vehicles are put in the tunnel — which can blow air at thousands of miles per hour — to study how they perform. Some of the test runs involved heat shields that pump liquids through channels just below the model's skin to cool it off, but not all models survived.

"I've seen instances where you'll get one clogged channel ... and it will immediately result in burn-throughs," Engelund said. "A model will disappear in a hypersonic wind tunnel. It almost vaporizes, there's so much energy and so much heat."

Musk has said that using methane as a coolant might be better than water.

"Rapid water vaporization can counter-intuitively cause it to snap freeze & block cooling channels," he said in a Tweet last month.

But Engelund also sees challenges with the methane option. When exposed to high temperatures, carbon atoms in hydrocarbon fuel (like methane) can "coke" or stick together and turn solid. Such debris can then block fine structures like pores.

"I would be very worried about that," Engelund said, adding that another big concern would be impurities in fuels, which can also lead to clogs.

One possible way to address these issues, Engelund said, could be to simply add more pores than seems necessary, "just in case some small percentage of the perforations get clogged, or the channels flowing coolant to those perforations."

On top of issues like bird droppings and clogging, there's the fine dust that blows across Mars. This could get lodged inside Starship's fuel-oozing pores, and it may be difficult to find and remove those blockages while on the red planet.

"Inspection and certification, in general, would be a thing of a concern for a large-scale active system like that — particularly at Mars, where you don't have access to a big gantry or towers to climb up and inspect," Engelund said. "I suppose you could use drones. Maybe that's something he's thinking about."

Can Starship take the heat?

Musk has shared only bits and pieces of Starship's latest design and has not presented a complete picture to the public, as he has done in the past. (The renderings shown in this story are courtesy of Kimi Talvitie, a 3D artist.)

But Musk said in December that he would "provide a detailed explanation in March/April," pending successful launches of a "test hopper" prototype that the company is building in Texas.

Read more: SpaceX's giant rocket ship was damaged by powerful winds in Texas — the nosecone blew over, and Elon Musk says repairs will take weeks

In the meantime, Musk shared a video (above) that appears to show the testing of a metallic heat shield for Starship. It's still unclear how much research SpaceX has performed on the transpirational-cooling concept.

"It's a huge risk if they haven't worked to qualify and validate what they want to do," Herbert said. "But if they did, it could be a real winner for their new design."

If it doesn't work, Engelund said, it's not necessarily a dead end for Musk's Starship.

"He may find out it's untenable or too expensive to certify or test, and he might find a better idea," Engelund said. "He's been really good at that over his career."

SpaceX also expects constant tweaks and changes as engineers work to make Starship a reality.

"We are using the same rapid iteration in design approach that led to the success on the Falcon 1, Falcon 9, Falcon Heavy, and Dragon programs," a company representative told Business Insider in an email, referring to the company's latestrocket and spaceship designs.

But SpaceX rejects any comparisons between Starship and NASA's Curiosity rover.

"Curiosity was pushing the limits of 1970's Mars [entry, descent, and landing] technology including a specific parachute-based EDL architecture," SpaceX said. "We are taking an entirely different approach, leveraging what we have done with Falcon 9, and have ample opportunity to demonstrate it on Earth prior to flying to Mars."

Despite the high hurdles SpaceX appears to face in its quest to launch and land Starship on Mars, no expert we spoke with said SpaceX's system was implausible.

"They've surprised a lot of people, and have a lot of smart people working for them, and Elon seems to be really committed and dedicated to this," Engelund said. "Perhaps there are some things that we could do with them. I suspect there will be."

SEE ALSO: Defectors from SpaceX, Blue Origin, and Tesla are developing a remarkable technology called 'Stargate' to help colonize other planets

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Earth's air supply may reach nearly 400,000 miles into space — so far that the moon constantly flies through it

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  • Space begins at roughly 62 miles (100 kilometers) above the surface of Earth, but our planet's air supply stretches farther than this.
  • Scientists have discovered that Earth's atmosphere may actually extend nearly 400,000 miles into deep space — far more than previously understood.
  • "The moon flies through Earth's atmosphere," one of the researchers said.

The boundaries between planet Earth, the moon, and deep space just got fuzzier.

According to a new analysis of data recorded by a spacecraft more than 20 years ago, the outer fringes of our cozy planet's atmosphere stretch far beyond what is typically imagined.

In fact, Earth's supply of hydrogen gas — the lightest air molecule and element on the Periodic Table— may extend nearly 400,000 miles out.

That's plenty of reach to envelope the moon, which orbits our planet at an average distance of 238,856 miles away.

"The moon flies through Earth's atmosphere,"Igor Baliukin, a space physicist at Russia's Space Research Institute in Moscow, said in a European Space Agency (ESA) press release. "We were not aware of it until we dusted off observations made over two decades ago by the SOHO spacecraft."

Formally known as the Solar and Heliospheric Observatory, SOHO is operated jointly by NASA and the European Space Agency.

An international team of researchers including Baliukin published their research this month in the journal JGR Space Physics.

Why Earth's atmosphere extends farther than previously realized

apollo earth geocorona atmospheric gases air supply backlit halo nasa esa AS16 123 19650

The internationally recognized boundary of space is called the Karman Line, and it's a border that exists 62 miles (100 kilometers) above Earth's surface. But contrary to popular belief, Earth's atmosphere has no clear or official boundary.

Earth's gravity hugs most of the densest gases close to its surface, including oxygen, nitrogen, carbon dioxide, and water vapor. Meanwhile, hydrogen and other very light gases drift deep into space.

Our planet has a magnetic field that thankfully protects the atmosphere — without it, a never-ending stream of particles from the sun, called the solar wind, might blow all these gases into space. (Mars' magnetic dynamo, by contrast, shut down billions of years ago, leading to a catastrophic loss of its air supply.)

Scientists knew that fleeting amounts of hydrogen drift far enough into space to merge with the solar wind. But the boundaries or envelope of that hydrogen cloud — called the geocorona — has never been fully clear.

The geocorona is invisible to human eyes. Hydrogen absorbs and re-emits sunlight in ultraviolet light, though, so Apollo 16 astronauts were able to photograph Earth's tenuous hydrogen cloud with ultraviolet-light-sensitive film during their moon mission in 1972.

Read more: SpaceX just launched an Israeli mission toward the moon. If successful, it would be the world's first private lunar landing.

SOHO, which has been in operation for about 23 years, carries an ultraviolet-light-recording instrument called SWAN (short for "Solar Wind ANisotropies"). It was designed to study the sun's particles, which can have huge ramifications on Earth, such as solar storms that can disrupt satellites and take out electrical grids.

However, by carefully reanalyzing two-decade-old observations from SWAN, an international team of scientists narrowed the data down to study hydrogen around Earth.

earth atmosphere gases air supply boundary edge space soho illustration nasa esa AS16 123 19650

From that analysis, they learned that even the side of Earth that faces the sun has an envelope of hydrogen extending far beyond the moon's orbit.

Behind Earth, on its dark side, pressure from the solar wind pushes the planet's outermost atmosphere into a bulbous tail that extends around 391,000 miles (630,000 kilometers) into deep space.

"Astronauts on the lunar surface did not know that they were actually embedded in the outskirts of the geocorona,"Jean-Loup Bertaux, a geophysicist and coauthor of the new study, said in the release.

The researchers noted that the density of the hydrogen cloud is so fleetingly low that it's still a vacuum out there. But the discovery could nonetheless have significant ramifications for new observatories that study the universe in normally invisible wavelengths of light.

"Space telescopes observing the sky in ultraviolet wavelengths to study the chemical composition of stars and galaxies would need to take this into account," Jean-Loup said in the release.

SEE ALSO: The speed of light is torturously slow, and these 3 simple animations by a scientist at NASA prove it

DON'T MISS: SpaceX just launched an Israeli mission toward the moon. If successful, it would be the world's first private lunar landing.

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NOW WATCH: A city in China wants to launch an artificial moon into orbit by 2020 — here's what would happen if Earth really did have two moons

Stephen Hawking died 1 year ago today. Here are 15 of the most remarkable and memorable things he ever said.

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  • Theoretical physicist Stephen Hawking died exactly one year ago, on March 14, 2018.
  • In his later years, Hawking could only "speak" through eye-tracking software due to a neurodegenerative disease.
  • Hawking shared many carefully considered, insightful, and inspirational quotes and ideas throughout his life.

Stephen Hawking — a theoretical physicist, luminary, author, and many other things — died on March 14, 2018, a year ago today. By coincidence, the day is also Albert Einstein's birthday and a quirky mathematical holiday known as Pi Day.

In passing, Hawking left behind an incredible legacy for a human beings on Earth. He pioneered new understandings of basic physics, mysterious black holes, and the cosmos at large. What's more, he did so while struggling with a severe neurodegenerative disease that confined him to a wheelchair for the vast majority of his life.

The world-renowned scientist carefully contemplated and composed his thoughts with a special eye-tracking computer, and those words (many of them humorous) continue to inspire generations of people who were curious about how the universe works, where it came from, and where it may be headed.

Hawking supplied no shortage of remarkable insights about life, love, and science. Below, we've done our best to collect the most memorable things he said in his books, essays, interviews, TV show appearances, and more.

This story has been updated. It was originally published on March 17, 2018.

Kevin Loria contributed to this post.

SEE ALSO: 17 'facts' about space and Earth that you thought were true — but have been debunked by science

DON'T MISS: The US military released a study on warp drives and faster-than-light travel. Here's what a theoretical physicist thinks of it.

On coping with his disability:



On his life outlook:



On science and religion:



See the rest of the story at Business Insider

The first day of spring is finally here — for about 90% of us. Here's why equinoxes mark the changing of seasons.

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  • This year's spring or vernal equinox will happen on Wednesday, March 20.
  • Earth's rotation does not cause the spring equinox. Rather, equinoxes occur because the planet has a tilted axis.
  • Spring comes when the sun's warming rays line up perpendicular to Earth's axial tilt.
  • During an equinox at Earth's equator, the sun appears almost directly overhead.

The year's spring equinox, also called the March or vernal equinox, falls on Wednesday at precisely 5:58 p.m. ET, according to the National Weather Service.

This astronomical event signals the arrival of spring, winter's end, and the trend toward increasingly warm and bright days that come with the pending arrival of summer.

At least, that's the case for people who live in Earth's northern hemisphere, which roughly 90% of all human beings call home. (Blame Earth's shifting land masses for that fun fact.)

For those in the southern hemisphere, the milestone marks the official beginning of fall. The days down under are growing shorter, the weather is cooling off, and sunlight is growing dimmer as winter approaches.

What drives these all-important seasonal shifts? Technically, two things: Earth's tilted axis and the planet's orbit around the sun.

How the spring equinox works

The Earth orbits the sun once every 365 days and 6 hours. Our planet also rotates once per day around a tilted axis.

That tilt is about 23.5 degrees (for now), which means different parts of the world get bathed with various intensities of light over the course of a year. Meanwhile, the planet's rotation keeps the heating even, sort of like a 7,917-mile-wide rotisserie chicken made of rock and a little water.

The spring equinox occurs when the sun's warming rays line up perpendicular to Earth's axial tilt:

spring equiniox sunlight earth axis tilt bi graphics

If you stand directly on the equator as the equinox peaks, the sun will appear more or less directly overhead. Your shadow will also be at its absolute minimum. The sun sets and rises roughly 12 hours apart, too.

But this moment won't last, since the Earth makes its way around the sun at a speed of roughly 66,600 mph.

Uneven seasons

Our planet's orbit is elliptical and its center of gravity slightly offset from the sun, so the time it takes to cycle through the seasons isn't perfectly divvied up.

Read more: The speed of light is torturously slow, and these 3 simple animations by a scientist at NASA prove it

About 92 days and 19 hours after the spring equinox, the Earth will reach its summer solstice — when the most direct rays of the sun reach their northernmost latitude, called the Northern Tropic (or Tropic of Cancer). Another 93 days and six hours later, the fall or autumnal equinox will occur.

Then it's another 89 days and 19 hours to the winter solstice — when the most direct sunlight strikes the Southern Tropic (or Tropic of Capricorn) — and another 89 days to get back to the spring equinox.

earth equiniox solstice seasons spring summer fall winter sun bi graphics

The animation below, from NASA's Goddard Space Flight Center, shows this seasonal progression.

It was created using geosynchronous satellite images taken over Africa; such satellites fly around Earth in a geosynchronous orbit, which means they move fast enough to hover above one spot on the planet.

This creates a great opportunity to photograph Earth over the course of the year and see how the the angle of sun changes.

Take a look:

The truth about the egg-balancing trick

That whole business of only being able to balance an egg on-end during a solstice is a myth. You can balance an egg any time you please, thanks to very small pores in its shell.

Those pores create nearly invisible dimples in the shell upon which a (very, very) patient person can stand up the egg.

Don't look for any gravitational interplay between Earth and the sun to help you out either; that's far too weak to make a noticeable difference.

This is an updated version of a story that was originally published on March 19, 2018.

SEE ALSO: 17 'facts' about space and Earth that you thought were true — but have been debunked by science

DON'T MISS: Jupiter is so big it does not actually orbit the sun

Join the conversation about this story »

NOW WATCH: SpaceX just launched the first private moon mission and it marks a new phase in space flight

A 'major breakthrough' in physics helps explain why all matter in the universe wasn't quickly destroyed

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  • The early universe created equal parts of matter and antimatter, which should have all annihilated or destroyed themselves.
  • However, an asymmetry in the universe left behind more matter and enabled our existence today.
  • Particle physicists are using Large Hadron Collider experiments to find explanations for this imbalance, which they call "charge conjugation parity" or CP violations.
  • On Thursday, CERN said the LHC's "beauty" or LHCb experiment detected a new CP violation with 99.9999% certainty, firmly backing up theoretical predictions for its existence.
  • After the universe formed, particles that make up protons and neutrons within atoms, called quarks, may have had a 0.1% preference toward creating the matter instead of the antimatter.

Scientists on the LHCb experiment at the Large Hadron Collider at CERN have discovered a new way in which matter and antimatter behave differently.

With 99.9999% statistical certainty, LHCb scientists have observed a difference between the decays of matter and antimatter particles containing charm quarks.

This discovery opens up a new realm to study the differences between matter and antimatter and could help explain why we live in a matter-dominated universe.

"This is a major breakthrough in experimental physics," says Sheldon Stone, a professor at Syracuse Universe and collaborator on the LHCb experiment. "There's been many attempts to make this measurement, but until now, no one had ever seen it. It's a huge milestone in antimatter research."

Every structure in the universe — from the tiniest speck of dust to the mightiest star — is built from matter. But there is an equally qualified material for the job: antimatter.

Antimatter is nearly identical to matter, except that its charge and magnetic properties are reversed. Precision studies of antihydrogen atoms, for example, have shown that their characteristics are identical to hydrogen atoms to beyond the billionth decimal place.

Matter and antimatter cannot coexist in the same physical space because if they come into contact, they annihilate each other. This equal-but-opposite nature of matter and antimatter poses a conundrum for cosmologists, who theorize that the same amount of matter and antimatter should have exploded into existence during the birth of our universe.

But if that's true, all of that matter and antimatter should have annihilated one another, leaving nothing but energy behind.

Creating antimatter to explore the early universe

particle collisions

Particle physicists are looking for any tiny differences between matter and antimatter which could help explain why matter won out over antimatter in the early universe.

Lucky for them, antimatter is not a totally extinct species.

"We don't usually see antimatter in our world," says Ivan Polyakov, a postdoc at Syracuse University and internal LHCb reviewer for this new analysis. "But it can be produced when ordinary matter particles are smashed together at high energies, such as they do inside the Large Hadron Collider."

Read more: We toured a giant 'time machine' hiding outside New York City

The main way scientists study the tiny and rare particles produced during the LHC's collisions is by mapping how they decay and transform into more-stable byproducts.

"This gives us a sort of family lineage for our ­particle of interest," says Cesar da Silva, a scientist from Los Alamos National Lab and also a LHCb collaborator. "Once stable particles are measured by the detector, we can trace their ancestors to find the primordial generation of particles in the collision."

He added: "Because of quantum mechanics, we cannot predict what each single unstable particle will decay into, but we can figure out the probabilities for each possible outcome."

A 'beautiful' LHC experiment helps explain why we exist

large hadron collider beauty lhcb physics charm particle decay detector experiment cern

The new LHCb study looked at the decays of particles consisting of two bound quarks — the internal structural components of particles like protons and neutrons.

One version of this particle (called D0 by scientists) contained a charm quark and the antimatter version of the up quark, called an anti-up quark. The other version contained the reverse, an up quark and an anti-charm quark.

Scientists on the LHCb experiment identified tens of millions of both D0 and anti-D0 particles and counted how many times each transformed into one set of byproducts (a pair of particles called pions) versus another possible set (a pair of particles called kaons).

With everything else being equal, the ratio of these two possible outcomes should have been identical for both D0 and anti-D0 particles. But scientists found that the two ratios differed by a tenth of a percent — evidence that these charmed matter and antimatter particles are not totally interchangeable.

"They might look nearly identical from the outside, but they behave differently," Polyakov says. "This is the puzzle of antimatter."

The idea that matter and antimatter particles behave slightly differently is not new and has been observed previously in studies of particles containing strange quarks and bottom quarks. What makes this study unique is that it is the first time this asymmetry has been observed in particles containing charm quarks.

Previous experiments — including BaBar, Belle and CDF — endeavored to make this same measurement but fell short of collecting enough data to to tease out such a subtle effect. The huge amount of data generated since the start of LHC Run 2 combined with the introduction of more advanced methods to tag the particles of interest enabled scientists to collect enough matter and antimatter D0 particles to finally see these decay differences beyond a shadow of a doubt.

The next step is to see how this measurement fits with the theoretical models, which are still a little fuzzy on this prediction.

"Theorists will need to figure out if the Standard Model can explain this," Stone says. "We're pushing our field and this result will certainly be in the history books."

SEE ALSO: A ghostly particle detected in Antarctica has led astronomers to a super-massive spinning black hole called a 'blazar'

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NOW WATCH: Scientists won the Nobel Prize for detecting gravitational waves — here's why that matters

The Hubble telescope spotted an asteroid that has grown two tails — and scientists think it's ripping itself to pieces

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  • A 2.5-mile-wide asteroid called 6478 Gault was discovered in 1988.
  • The space rock recently grew two long, bright tails like a comet, which astronomers struggled to explain.
  • The Hubble telescope studied the tails in detail, while ground-based observatories helped confirm the asteroid was rapidly spinning.
  • Researchers figured that sunlight gradually spun up Gault's rotational speed to unstable levels — something called a "YORP effect."
  • Gault is spinning so quickly that a small pebble hitting the asteroid might have caused it to slough off dirt and dust, forming its tails.

In space, no one can hear an asteroid scream. But astronomers just used the Hubble telescope to see one destroying itself.

A 2.5-mile-wide asteroid called 6478 Gault was first discovered in 1988, and it seemed like many of the other 800,000 known space rocks.

But in January, astronomers saw something strange in survey telescope images: Gault had become "active" and sprouted a big, bright tail — much like a comet's — that stretched more than 500,000 miles long. A dimmer second tail was found several weeks later.

Some space rocks that initially look like asteroids are later found to be comets when they pass close to the sun. The boost in solar energy can warm up ice and other frozen compounds hidden under layers of dust, turning those materials into gases and leading the rock to spew out comet debris to form a long, glowing tail.

Gault didn't seem to fit the bill, though, since it lurks about 214 million miles away from the sun in a fairly circular orbit between Mars and Jupiter. In other words, it never swung close to the sun. So scientists wondered if another space rock had collided with Gault, splashing its dusty guts all over space.

Now, thanks to multiple observations by NASA and the European Space Agency's Hubble Space Telescope, the mystery appears to be solved: Gault is spinning itself to pieces.

"This self-destruction event is rare,"Olivier Hainaut, an astronomer with the European Southern Observatory, said in a press release. "Active and unstable asteroids such as Gault are only now being detected by means of new survey telescopes that scan the entire sky, which means asteroids such as Gault that are misbehaving cannot escape detection any more."

Hainaut and his colleagues around the world have submitted a study about the discovery to Astrophysical Journal Letters, which accepted it for publication in the future.

The team determined an odd behavior called the "YORP effect" is to blame for the ongoing demise of Gault, which could vanish

You YORP me right round

asteroid 6478 gault orbit solar system earth mars sun esa hubble labeled

The YORP effect is named after four scientists that helped lead to its discovery: Ivan Yarkovsky, John O'Keefe, Vladimir Radzievskii, and Stephen Paddack.

What powers it is sunlight. When we step outside, light from the sun feels warm on our skin, but not like a force powerful enough to physically move us. Yet in the vacuum of space, things behave differently: There's no friction, and objects can orbit a star and persist for millions if not billions of years.

Even on human-made objects, like a thin reflective sheet, sunlight can generate enough force to propel a vehicle through space. (Scientists are currently exploring how to mimic that effect by shooting powerful laser beams at tiny spacecraft to zoom them toward other star systems at a fraction of light-speed.)

The YORP effect describes a phenomenon in which sunlight hits an asteroid unevenly, or part of the rock's surface preferentially absorbs that energy. In that case, the disparity can gradually accelerate a comet's spin. Over time, that can lead the space rock to start spinning so fast that it rips itself apart.

That, the researchers figured, could explain why Gault grew tails so far from the sun (see above animation).

Read more: Alexandria Ocasio-Cortez has an asteroid named after her — here's why

The effect is something like a parent swinging a kid around by her arms; once the parent rotates fast enough, the kid will eventually lift off the ground. In the case of Gault, Hubble's images — plus follow-up observations by telescopes on Earth — suggested that the asteroid was spinning about once every two hours. The researchers calculated that this was fast enough to counteract Gault's gravity at the surface, allowing dirt and dust to lift off or tumble.

But what caused Gault's sudden outburst and tail formation in late 2018, after untold years of inactivity?

"Even a tiny disturbance, like a small impact from a pebble, might have triggered the recent outbursts,"Jan Kleyna, an astronomer at the University of Hawaii and the study's lead author, said in a press release. "It could have been on the brink of instability for 10 million years."

Hainaut said the long-term future of Gault is unknown. It might eventually break apart into two big chunks, or the rubble might glue itself back together under its own gravity, forming a newly shaped asteroid.

"In all cases, this will release a lot of dust, which will be spectacular," Hainaut told Business Insider in an email. "The radiation pressure from the sun will disperse the dust, leaving either the new Gault or the binary/multiple system behind."

Given the number of asteroids in the solar system, Kleyna, Hainaut, and their colleagues now expect ever-improving all-sky survey telescopes to see sudden outbursts like Gault's about once a year.

This story has been updated.

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