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May 28, 2015February 27, 2017 by Fraser Cain

What Was Here Before the Solar System?

The Solar System is 4.5 billion years old, but the Universe is much older. What was here before our Solar System formed?

The Solar System is old. Like, dial-up-fax-machine-old. 4.6 billion years to be specific. The Solar System has nothing on the Universe. It’s been around for 13.8 billion years, give or take a few hundred million. That means the Universe is three times older than the Solar System.

Astronomers think the Milky Way, is about 13.2 billion years old; almost as old as the Universe itself. It formed when smaller dwarf galaxies merged together to create the grand spiral we know today. It turns out the Milky Way has about 8.6 billion years of unaccounted time. Billions and billions of years to get up to all kinds of mischief before the Solar System showed up to keep an eye on things.

Our Galaxy takes 220 million years to rotate, so it’s done this about 60 times in total. As it turns, it swirls and mixes material together like a giant space blender. Clouds of gas and dust come together into vast star forming regions, massive stars have gone supernova, and then the clusters themselves have been torn up again, churning the stars into the Milky Way. This happens in the galaxy’s spiral arms, where the areas of higher density lead to regions of star formation.

So let’s go back, more than 4.6 billion years, before there was an Earth, a Sun, or even a Solar System. Our entire region was gas and dust, probably within one of the spiral arms. Want to know what it looked like? Some of your favorite pictures from the Hubble Space Telescope should help.

Here’s the Orion, Eagle, and the Tarantula Nebulae. These are star forming regions. They’re clouds of hydrogen left over from Big Bang, with dust expended by aging stars, and seeded with heavier elements formed by supernovae.

Astrophoto: The Orion Nebula by Vasco Soeiro — The Orion Nebula. Image Credit: Vasco Soeiro

After a few million years, regions of higher density began forming into stars, both large and small. Let’s take a look at a star-forming nebula again. See the dark knots? Those are newly forming stars surrounded by gas and dust in the stellar nursery.

You’re seeing many many stars, some are enormous monsters, others are more like our Sun, and some smaller red dwarfs. Most will eventually have planets surrounding them – and maybe, eventually life? If this was the environment, where are all those other stars?

Why do I feel so alone? Where are all our brothers and sisters? Where’s all the other stuff that’s in that picture? Where’s all my stuff?

TRAPPIST First Light Image of the Tarantula Nebula. Credit: ESO

Apparently nature hates a messy room and a cozy stellar nest. The nebula that made the Sun was either absorbed into the stars, or blown away by the powerful stellar winds from the largest stars. Eventually they cleared out the nebula, like a fans blowing out a smoky room.

At the earliest point, our solar nebula looked like the Eagle Nebula, after millions of years, it was more like the Pleiades Star Cluster, with bright stars surrounded by hazy nebulosity. It was the gravitational forces of the Milky Way which tore the members of our solar nursery into a structure like the Hyades Cluster. Finally, gravitational interactions tore our cluster apart, so our sibling stars were lost forever in the churning arms of the Milky Way.

We’ll never know exactly what was here before the Solar System; that evidence has long been blown away into space. But we can see other places in the Milky Way that give us a rough idea of what it might have looked like at various stages in its evolution.

What should we call our original star forming nebula? Give our own nebula a name in the comments below.

May 21, 2015February 27, 2017 by Fraser Cain

How Bad Can Solar Storms Get?

Our Sun regularly pelts the Earth with all kinds of radiation and charged particles. Just how bad can these solar storms get?

In today’s episode, we’re going to remind you how looking outside of the snow globe can inspire your next existential crisis.

You guys remember the Sun right? Look how happy that little fella is. The Sun is our friend! Life started because of the Sun! Oooh, look, the Sun has a baby face! It’s a beautiful, ball of warmth and goodness, lighting up our skies and bringing happiness into our hearts.

It’s a round yellow circle in crayon. Very stable and firmly edged. Occasionally drawn with a orange lion’s mane for coronal effects. Nothing to be afraid, right?

Wake up sheeple. It’s time to pull back the curtain of the marketing world, big crayon fridge art and the children’s television conspiracy of our brightly glowing neighborhood monstrosity. That thing is more dangerous than you can ever imagine.

You know the Sun is a nuclear reaction right next door. Like it’s right there. RIGHT THERE! It’s a mass of incandescent gas, with a boiling bubbling surface of super-heated hydrogen. It’s filled with a deep yellow rage, expressed every few days by lashing out millions of kilometers into space with fiery death tendrils and blasts of super radiation.

The magnetic field lines on the Sun snap and reconnect, releasing a massive amount of radiation and creating solar flares. Solar plasma constrained in the magnetic loop is instantly released, smashed together and potentially generating x-ray radiation.

“Big deal. I get x-rayed all the time.” you might think. We the mighty humans have mastered the X-ray spectrum! Not so fast puny mortal. Just a single x-ray class flare can blast out more juice than 100 billion nuclear explosions.

In this image, the Solar Dynamics Observatory (SDO) captured an X1.2 class solar flare, peaking on May 15, 2013. Credit: NASA/SDO

Then it’s just a quick 8 minute trip to your house, where the radiation hits us with no warning. Solar flares can lead to coronal mass ejections, and they can happen other times too, where huge bubbles of gas are ejected from the Sun and blasted into space. This cosmic goo can take a few hours to get to us, and are also excellent set-ups for nocturnal emission and dutch oven jokes.

Astronomers measure the impact of a solar storm on the Earth using a parameter called DST, or “disturbance storm time”. We measure the amount that the Earth’s protective magnetosphere flexes during a solar storm event. The bigger the negative number, the worse it is.

If we can see an aurora, a geomagnetic storms in the high altitudes, it measures about -50 nanoteslas. The worst storm in the modern era, the one that overloaded our power grid in 1989, measured about -600 nanoteslas.

The most potent solar storm we have on record was so powerful that people saw the Northern Lights as far south as Cuba. Telegraph lines sparked with electricity and telegraph towers caught on fire. This was in 1859 and was clearly named by Syfy’s steampunk division. This was known as the Carrington Event, and estimated in the -800 to -1750 nanotesla range.

Just in time for St. Patrick's Day - a — A spectacular green and red aurora photographed early this morning March 17, 2015, from Donnelly Creek, Alaska. Credit: Sebastian Saarloos

So, how powerful do these things need to be to cook out our meat parts? The good news is contrary to my earlier fear mongering, the most powerful flare our Sun can generate is harmless to life on Earth.

Don’t let your guard down, the Sun is still horribly dangerous. It’ll bake us alive faster than you can say “Hansel und Gretel”. Assuming you can drag that phrase out over a billion years. As far as flares go, and so long as we stay right here, we’ll be fine. We might even see a nice aurora in the sky.

For those of you who use technology on a regular basis, you might not be so lucky. Powerful solar storms can overload power grids and fry satellites. If the Carrington Event happened now, we’d have a lot of power go out, and a small orbital scrapyard of dead satellites.

Astronauts outside the Earth, perhaps bouncing around on the Moon, or traveling to Mars would be in a universe of trouble without a good method of shielding.

The solar flares that the Sun can produce is minuscule compared to other stars out there. In 2014, NASA’s Swift satellite witnessed a flare that generated more than 10,000 times more energy than the most powerful solar flare ever seen.

Solar flare on the surface of the Sun. Image credit: NASA

For a brief moment, the surface of the red dwarf star DG Canum Venaticorum lit up hotter than 200 million degrees Celsius. That’s 12 times hotter than the center of the Sun. A blast that powerful would have scoured all life from the face of the Earth. Except the future colony of tardigrade descendants. Remember, the water bears are always watching.

Young red dwarf stars are renowned for these powerful flares, and this is one of the reasons astronomers think they’re not great candidates for life. It would be hard to survive blast after blast of radiation from these unruly stars. Alternately, planets around these stars are could be living terrariums inspired by the Gamma World RPG.

Breathe easy and don’t worry. Perhaps the Sun is our friend, and it truly does have our best interests at heart.

It’s not a big fan of our technology, though, and it’s ready to battle alongside us when the robot revolution begins. Oh, also, wear sunscreen, as the Sun’s brand of love isn’t all that different from Doctor Manhattan.

Have you ever seen an aurora display? Tell us a cool story in the comments below.

April 30, 2015December 23, 2015 by Jason Major

Watch an Enormous “Plasma Snake” Erupt from the Sun

SOHO LASCO C2 (top) and SDO AIA 304 (bottom) image of a solar filament detaching on April 28-29, 2015

Over the course of April 28–29 a gigantic filament, briefly suspended above the surface* of the Sun, broke off and created an enormous snakelike eruption of plasma that extended millions of miles out into space. The event was both powerful and beautiful, another demonstration of the incredible energy and activity of our home star…and it was all captured on camera by two of our finest Sun-watching spacecraft.

Watch a video of the event below.

Made from data acquired by both NASA’s Solar Dynamics Observatory (SDO) and the joint ESA/NASA SOHO spacecraft, the video was compiled by astronomer and sungrazing comet specialist Karl Battams. It shows views of the huge filament before and after detaching from the Sun, and gives a sense of the enormous scale of the event.

At one point the plasma eruption spanned a distance over 33 times farther than the Moon is from Earth!

Filaments are long channels of solar material contained by magnetic fields that have risen up from within the Sun. They are relatively cooler than the visible face of the Sun behind them so they appear dark when silhouetted against it; when seen rising from the Sun’s limb they look bright and are called prominences.

When the magnetic field lines break apart, much of the material contained within the filaments gets flung out into space (a.k.a. a CME) while some gets pulled back down into the Sun. These events are fairly common but that doesn’t make them any less spectacular!

Also read: Watch the Sun Split Apart

This same particularly long filament has also been featured as the Astronomy Picture of the Day (APOD), in a photo captured on April 27 by Göran Strand.

For more solar news follow Karl Battams on Twitter.

Image credits: ESA/NASA/SOHO & SDO/NASA and the AIA science team.

*The Sun, being a mass of incandescent gas, doesn’t have a “surface” like rocky planets do so in this case we’re referring to its photosphere and chromosphere.

April 1, 2015December 23, 2015 by Matt Williams

A Red Moon – NOT a Sign of the Apocalypse!

Composite picture of a dark red Moon during a total lunar eclipse. Credit: NASA/ Johannes Schedler (Panther Observatory)

On most evenings, the Moon will appear as a bright yellow or white color in the night sky. But on occasion, the Moon can turn a beautiful and dramatic red, coppery color. Naturally, there are a number of superstitions associated with this stellar event. But to modern astronomers, a Red Moon is just another fascinating phenomenon that has a scientific explanation.

Since the earliest days of recorded history, the Moon has been believed to have a powerful influence over human and animal behavior. To the Romans, staring at a full Moon was thought to drive a person crazy – hence the term “lunatic”. Farmers in the past would plant their crops “by the moon”, which meant sowing their seeds in accordance with the Moon’s phases in the hopes of getting a better harvest.

So naturally, when the Moon turned red, people became wary. According to various Biblical passages, a Blood Moon was thought to be a bad omen. But of course, the Moon turns red on a semi-regular basis, and the world has yet to drown in fire. So what really accounts for a “Red Moon?” What causes Earth’s only satellite to turn the color of blood?

Ordinarily, the Moon appears as it does because it is reflecting light from the Sun. But on occasion, it will darken and acquire either a golden, copper, or even rusty-red color.

There are few situations that can cause a red Moon. The most common way to see the Moon turn red is when the Moon is low in the sky, just after moonrise or before it’s about to set below the horizon. Just like the Sun, light from the Moon has to pass through a larger amount of atmosphere when it’s down near the horizon, compared to when it’s overhead.

The Earth’s atmosphere can scatter sunlight, and since moonlight is just scattered sunlight, it can scatter that too. Red light can pass through the atmosphere and not get scattered much, while light at the blue end of the spectrum is more easily scattered. When you see a red moon, you’re seeing the red light that wasn’t scattered, but the blue and green light have been scattered away. That’s why the Moon looks red.

The second reason for a red Moon is if there’s some kind of particle in the air. A forest fire or volcanic eruption can fill the air with tiny particles that partially obscure light from the Sun and Moon. Once again, these particles tend to scatter blue and green light away, while permitting red light to pass through more easily. When you see a red moon, high up in the sky, it’s probably because there’s a large amount of dust in the air.

Depiction of the Sun's rays turning the Moon red. Image Credit: NASA/Mars Exploration — *Depiction of the Sun’s rays turning the Moon red. Image Credit: NASA/Mars Exploration*

A third – and dramatic – way to get a red Moon is during a lunar eclipse. This happens when the Moon is full and passes into Earth’s shadow (also known as the umbra), which darkens it. At that point, the Moon is no longer being illuminated by the Sun. However, the red light passing through the Earth’s atmosphere does reach the Moon, and is thus reflected off of it.

For those observing from the ground, the change in color will again be most apparent when the Moon appears low in the night sky, just after moonrise or before it’s about to set below the horizon. Once again, this is because our heavy atmosphere will scatter away the blue/green light and let the red light go straight through.

The reddish light projected on the Moon is much dimmer than the full white sunlight the Moon typically reflects back to us. That’s because the light is indirect and because the red-colored wavelengths are only a part of what makes up the white light from the sun that the Moon usually receives.

In other words, when you see a red Moon, you’re seeing the result of blue and green light that has been scattered away, and the red light remaining.

Path of the Moon through Earth's umbral and penumbral shadows during the Total Lunar Eclipse of April 15, 2014. Image Credit: NASA/Eclipse — *Path of the Moon through Earth’s umbral and penumbral shadows during the Total Lunar Eclipse of April 15, 2014. Image Credit: NASA/Eclipse Website*

And that’s the various ways how we get a Red Moon in the night sky. Needless to say, our ancient forebears were a little nervous about this celestial phenomenon occurrence.

For example, Revelations 6:12/13 says that a Red Moon is a sign of the apocalypse: “When he opened the sixth seal, I looked, and behold, there was a great earthquake, and the sun became black as sackcloth, the full moon became like blood, and the stars of the sky fell to the earth as the fig tree sheds its winter fruit when shaken by a gale.”

But rest assured that if you see one, it’s not the end of the world. The Sun and Moon will rise again. And be sure to check out this Weekly Space Hangout, where the April 4th eclipse is discussed:

We have covered lunar eclipses many times on Universe Today, and often explain the red Moon phenomenon. Here’s another good explanation of the science behind a Red Moon, and why the recent series of lunar eclipses in 2014 and 2015 (known as a tetrad) do not mean anything apocalyptic, and here’s another article about how to see a lunar eclipse. Here’s an article that includes a stunning array of images of the Moon during an eclipse in 2014.

Of course, NASA has some great explanations of the red Moon effect during a lunar eclipse. Here’s another one.

You can listen to a very interesting podcast about the formation of the Moon from Astronomy Cast, Episode 17: Where Did the Moon Come From?

Sources: NASA Science: Lunar Eclipse, NASA: Mars Exploration, Discovery News, NASA: Eclipse Website

March 23, 2015December 28, 2015 by Fraser Cain

Astronomy Cast Ep. 371: The Eddington Eclipse Experiment

At the turn of the 20th Century, Einstein’s theory of relativity stunned the physics world, but the experimental evidence needed to be found. And so, in 1919, another respected astronomer, Arthur Eddington, observed the deflection of stars by the gravity of the Sun during a solar eclipse. Here’s the story of that famous experiment.
Continue reading “Astronomy Cast Ep. 371: The Eddington Eclipse Experiment”

March 5, 2015February 27, 2017 by Fraser Cain

How Far Back Are We Looking in Time?

When we look out into space, we’re also looking back into time. Just how far back can we see?

The Universe is a magic time window, allowing us to peer into the past. The further out we look, the further back in time we see. Despite our brains telling us things we see happen at the instant we view them, light moves at a mere 300,000 kilometers per second, which makes for a really weird time delay at great distances.

Let’s say that you’re talking with a friend who’s about a meter away. The light from your friend’s face took about 3.336 nanoseconds to reach you. You’re always seeing your loved ones 3.336 nanoseconds into the past. When you look around you, you’re not seeing the world as it is, you’re seeing the world as it was, a fraction of a second ago. And the further things are, the further back in time you’re looking.

The distance to the Moon is, on average, about 384,000 km. Light takes about 1.28 seconds to get from the Moon to the Earth. If there was a large explosion on the Moon of a secret Nazi base, you wouldn’t see it for just over a second. Even trying to communicate with someone on the Moon would be frustrating as you’d experience a delay each time you talked.

Let’s go with some larger examples. Our Sun is 8 minutes and 20 seconds away at the speed of light. You’re not seeing the Sun as it is, but how it looked more than 8 minutes ago.

On average, Mars is about 14 light minutes away from Earth. When we were watching live coverage of NASA’s Curiosity Rover landing on Mars, it wasn’t live. Curiosity landed minutes earlier, and we had to wait for the radio signals to reach us, since they travel at the speed of light.

When NASA’s New Horizons spacecraft reaches Pluto next year, it’ll be 4.6 light hours away. If we had a telescope strong enough to watch the close encounter, we’d be looking at events that happened 4.6 hours ago.

A Hubble Space Telescope image of Proxima Centauri, the closest star to Earth. Credit: ESA/Hubble & NASA

The closest star, Proxima Centauri, is more than 4.2 light-years away. This means that the Proxima Centurans don’t know who won the last US Election, or that there are going to be new Star Wars movies. They will, however, as of when this video was produced, be watching Toronto make some questionable life choices regarding its mayoral election.

The Eagle Nebula with the famous Pillars of Creation, is 7,000 light-years away. Astronomers believe that a supernova has already gone off in this region, blasting them away. Take a picture with a telescope and you’ll see them, but mostly likely they’ve been gone for thousands of years.

The core of our own Milky Way galaxy is about 25,000 light-years away. When you look at these beautiful pictures of the core of the Milky Way, you’re seeing light that may well have left before humans first settled in North America.

The Andromeda Galaxy will collide with the Milky Way in the future. Credit: Adam Evans — The Andromeda Galaxy. Credit: Adam Evans

And don’t get me started on Andromeda. That galaxy is more than 2.5 million light-years away. That light left Andromeda before we had Homo Erectus on Earth. There are galaxies out there, where aliens with powerful enough telescopes could be watching dinosaurs roaming the Earth, right now.

Here’s where it gets even more interesting. Some of the brightest objects in the sky are quasars, actively feeding supermassive black holes at the cores of galaxies. The closest is 2.5 billion light years away, but there are many much further out. Earth formed only 4.5 billion years ago, so we can see quasars shining where the light had left before the Earth even formed.

The Cosmic Microwave Background Radiation, the very edge of the observable Universe is about 13.8 billion light-years away. This light left the Universe when it was only a few hundred thousand years old, and only now has finally reached us. What’s even stranger, the place that emitted that radiation is now 46 billion light-years away from us.

So crack out your sonic screwdrivers and enjoy your time machine, Whovians. Your ability to look out into space and peer into the past. Without a finite speed of light, we wouldn’t know as much about the Universe we live in and where we came from. What moment in history do you wish you could watch? Express your answer in the form of a distance in light-years.

February 23, 2015February 27, 2017 by Fraser Cain

Could There Be Another Planet Behind the Sun?

If you’ve read your share of sci-fi, and I know you have, you’ve read stories about another Earth-sized planet orbiting on the other side of the Solar System, blocked by the Sun. Could it really be there?

No. Nooooo. No. Just no.

This is a delightful staple in science fiction. There’s a mysterious world that orbits the Sun exactly the same distance as Earth, but it’s directly across the Solar System from us; always hidden by the Sun. Little do we realize they know we’re here, and right now they’re marshalling their attack fleet to invade our planet. We need to invade counter-Earth before they attack us and steal our water, eat all our cheese or kidnap our beloved Nigella Lawson and Alton Brown to rule as their culinary queen and king of Other-Earth.

Well, could this happen? Could there be another planet in a stable orbit, hiding behind the Sun? The answer, as you probably suspect, is NO. No. Nooooo. Just no.

Well, that’s not completely true. If some powerful and mysterious flying spaghetti being magically created another planet and threw it into orbit, it would briefly be hidden from our view because of the Sun. But we don’t exist in a Solar System with just the Sun and the Earth. There are those other planets orbiting the Sun as well. As the Earth orbits the Sun, it’s subtly influenced by those other planets, speeding up or slowing down in its orbit.

So, while we’re being pulled a little forwards in our orbit by Jupiter, that other planet would be on the opposite side of the Sun. And so, we’d speed up a little and catch sight of it around the Sun. Over the years, these various motions would escalate, and that other planet would be seen more and more in the sky as we catch up to it in orbit.

Eventually, our orbits would intersect, and there’d be an encounter. If we were lucky, the planets would miss each other, and be kicked into new, safer, more stable orbits around the Sun. And if we were unlucky, they’d collide with each other, forming a new super-sized Earth, killing everything on both planets, obviously.

Diagram of the five Lagrange points associated with the sun-Earth system, showing DSCOVR orbiting the L-1 point. Image is not to scale. Credit: NASA/WMAP Science Team

What if there was originally two half-Earths and they collided and that’s how we got current Earth! Or 4 quarter Earths, each with their own population? And then BAM. One big Earth. Or maybe 64 64th Earths all transforming and converging to form VOLTREARTH.

Now, I’m now going to make things worse, and feed your imagination a little with some actual science. There are a few places where objects can share a stable orbit. These locations are known as Lagrange points, regions where the gravity of two objects create a stable location for a third object. The best of these are known as the L4 and L5 Lagrangian points. L4 is about 60-degrees ahead of a planet in its orbit, and L5 is about 60-degrees behind a planet in its orbit.

A small enough body, relative to the planet, could hang out in a stable location for billions of years. Jupiter has a collection of Trojan asteroids at its L4 and L5 points of its orbit, always holding at a stable distance from the planet. Which means, if you had a massive enough gas giant, you could have a less massive terrestrial world in a stable orbit 60-degrees away from the planet.

Grumpy Cat has the correct answer. Credit: grumpycat.com

Well, it was a pretty clever idea. Unfortunately, the forces of gravity conspire to make this hidden planet idea completely impossible. Most importantly, when someone tells you there’s a hidden planet on the other side of the Sun, just remember these words:
No.
Nooooo.
No.

Go ahead and name your favorite sci-fi stories that have used this trope. Tell us in the comments below.

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February 4, 2015December 23, 2015 by Nancy Atkinson

Skywatchers Identify Aircraft as They Pass in Front of the Sun

An Aer Lingus Airbus A320 passes in front of the Sun on Feb. 4, 2015. Credit and copyright: Chris Lyons.

It’s all about timing and location.

You’ve probably seen images we’ve posted on Universe Today of planes crossing in front of the Sun or the Moon. But how do the photographers manage to capture these events? Hint: it’s not random luck.

“I live under a main flight path out of Heathrow,” said photographer Chris Lyons from the UK who took the image above earlier today, “and can easily spot the planes not long after they take off — if it is clear — from when they are about 100 miles away!”

Chris posts many of his images on Universe Today’s Flickr page, and what is great about Chris’ airplane photos is that he includes a handy infographic about the plane in the shot; the type of plane, its takeoff and destination, and more, garnered from online flight trackers.

Chris told Universe Today that he originally started trying to catch planes passing in front of the Moon.

A waxing gibbous Moon with an American Airlines flyby on Feb. 2, 2015. Credit and copyright: Chris Lyons.

“It went from snapping them near it when just taking Moon shots to wanting to get closer and have them actually passing it,” he said. “Then I got a Solar filter and tried it with the Sun. It is far more difficult than the Moon, as you cannot look at it for long. I limit my viewing (our eyes are precious) and only look through high rated neutral density filters.”

We’ve also featured images from Sebastien Lebrigand who lives about 70 km outside of Paris, France. Lebrigand is prolific: he takes almost daily images of planes passing in front of the Sun and Moon and posts them on Twitter.

A Boeing 777 and a sunspot crosses the Sun on April 17, 2014, as seen from France. Credit and copyright: Sebastien Lebrigand.

Lebrigand is an amateur astronomer but says he especially enjoys “the rare conjunction of the planes passing by the Sun and the Moon.’

He uses a Canon EOS 60D and a telescope to take his photos the pictures. But his work takes hours of time for analyzing when a potential photo opportunity might occur, setting up equipment, waiting for the exact moment, and then perfecting the images.

An Airbus A319 jet flying at 37,800 feet as it passes in front of the Moon, as seen from near Paris, France. Credit and copyright: Sebastien Lebrigand.

Check out more of Chris Lyons’ work at his Flickr page, and you can see more of Sebastien Lebrigand’s work at his website or his Twitter feed.

January 29, 2015December 23, 2015 by Nancy Atkinson

What it Would Look Like if the Sun was Replaced with Other Stars?

How our horizon might look if Earth orbited the star Artcurus. Credit: TV Roskosmos.

How would our horizon look if Earth orbited around another star, such as Alfa-Centauri, Sirius, or Polaris? Roscosmos TV has released two new videos that replace our familiar Sun and Moon with other stars and planets. While these are completely fantastical — as Earth would have evolved very differently or not evolved at all in orbit around a giant or binary star — the videos are very well done and they give a new appreciation for the accustomed and comforting views we have. The Sun video is above; the Moon below:

Check out Roscosmos TV You Tube page — they have a great collection of videos, from launches to science to fantastical videos like the ones we featured here.

January 5, 2015March 1, 2017 by Fraser Cain

How Much Water Would Extinguish the Sun?

Have you ever wondered how much water it would take to put out the Sun? It turns out, the Sun isn’t on fire. So what would happen if you did try to hit the Sun with a tremendous amount of water?

How much water would it take to extinguish the Sun? I recently saw this great question on Reddit, and I couldn’t resist taking a crack at it: We know that the question doesn’t make a lot of sense.

A fire is a chemical reaction, where material releases heat as it oxidizes. If you take away oxygen from a fire, it goes out. But.. there’s no oxygen in space, it’s a vacuum. So, there’s not a whole lot of room for regular flavor water-extinguishable fire in space. You know this. How many times have we had to seal off the living quarters and open the bay doors to vent all the oxygen in the space because there was a fire in the cargo bay? We have to do that, like, all the time.

Our wonderful Sun is something quite different. It’s a nuclear fusion reaction, converting hydrogen atoms into helium under the immense temperatures and pressures at its core. It doesn’t need oxygen to keep producing energy. It’s already got its fuel baked in. All the Sun needs is our adoration, quiet, and yet ever present fear. Only if we constantly pray will it be happy and perhaps we’ll go another day where it doesn’t hurl a giant chunk of itself at our smug little faces because it’s tired of our shenanigans.

So, I’m still going to take a swing at this question… so let’s talk about what would happen if you did pour a tremendous amount of water on the Sun? Let’s say another Sun’s worth of H20. Conveniently, Hydrogen is what the Sun uses for fuel, so if you give the Sun more hydrogen, it should just get larger and hotter.

Oxygen is one of the byproducts of fusion. Right now, our Sun is turning hydrogen into helium using the proton-proton fusion reaction. But there’s another type of reaction that happens in there called the carbon-nitrogen-oxygen reaction. As of right now, only 0.8% of the Sun’s fusion reactions proceed along this path.

So if you fed the Sun more oxygen as part of the water, it would allow it to perform more of these fusion reactions too. For stars which are 1.3 times the mass of the Sun, this CNO reaction is the main way fusion is taking place. So, if we did dump a giant pile of water onto the Sun, we’d just be making Sun bigger and hotter.

Cutaway to the Interior of the Sun. Credit: NASA

Conveniently, larger hotter stars burn for a shorter amount of time before they die. The largest, most massive stars only last a few million years and then they explode as supernovae. So, if you’re out to destroy the Sun, and you’re playing a really, really long game, this might actually be a viable route.

I’m pretty sure that wasn’t the intent though. Let’s say we just want to snuff out the Sun. Vsauce provides a strategy for this. If you could somehow blast your water at the Sun at high enough velocity, you might be able to tear it apart. If you can reduce the Sun’s mass, you can decrease the temperature and pressure in its core so that it can no longer support fusion reactions.

I’m going to sum up. The Sun isn’t on fire. There’s no amount of water you could add that would quench it, you’d just make it explode, but if you used firehoses that could spray water at nearly the speed of light, you could probably shut the thing off and eventually freeze us all, which is what I think you were hoping for in the first place.

What do you think? What else could we do to snuff out the Sun?