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Citizen Scientists Discover Yellow “Space Balls”

Citizen scientists scanning images from NASA’s Spitzer Space Telescope, an orbiting infra-red observatory, recently stumbled upon a new class of curiosities that had gone largely unrecognized before: yellow balls.

“The volunteers started chatting about the yellow balls they kept seeing in the images of our galaxy, and this brought the features to our attention,” said Grace Wolf-Chase of the Adler Planetarium in Chicago.

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A new ScienceCast video examines “yellow balls” and their role in star formation. Play it

The Milky Way Project is one of many “citizen scientist” projects making up the Zooniverse website, which relies on crowdsourcing to help process scientific data.  For years, volunteers have been scanning Spitzer’s images of star-forming regions—places where clouds of gas and dust are collapsing to form clusters of young stars.  Professional astronomers don’t fully understand the process of star formation; much of the underlying physics remains a mystery. Citizen scientists have been helping by looking for clues.

Before the yellow balls popped up, volunteers had already noticed green bubbles with red centers, populating a landscape of swirling gas and dust. These bubbles are the result of massive newborn stars blowing out cavities in their surroundings. When the volunteers started reporting that they were finding objects in the shape of yellow balls, the Spitzer researchers took note.

Auroras Underfoot (signup)

The rounded features captured by the telescope, of course, are not actually yellow, red, or green—they just appear that way in the infrared, color-assigned images that the telescope sends to Earth. The false colors provide a way to humans to talk about infrared wavelengths of light their eyes cannot actually see.

“With prompting by the volunteers, we analyzed the yellow balls and figured out that they are a new way to detect the early stages of massive star formation,” said Charles Kerton of Iowa State University, Ames. “The simple question of ‘Hmm, what’s that?’ led us to this discovery.”

A thorough analysis by the team led to the conclusion that the yellow balls precede the green bubbles, representing a phase of star formation that takes place before the bubbles form.

“Basically, if you wind the clock backwards from the bubbles, you get the yellow balls,” said Kerton.

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An artist’s concept shows how “yellow balls” fit into the process of star formation.

Researchers think the green bubble rims are made largely of organic molecules called polycyclic aromatic hydrocarbons (PAHs). PAHs are abundant in the dense molecular clouds where stars coalesce. Blasts of radiation and winds from newborn stars push these PAHs into a spherical shells that look like green bubbles in Spitzer’s images. The red cores of the green bubbles are made of warm dust that has not yet been pushed away from the windy stars.

How do the yellow balls fit in?

“The yellow balls are a missing link,” says Wolf-Chase. They represent a transition “between very young embryonic stars buried in dense, dusty clouds and slightly older, newborn stars blowing the bubbles.”

Essentially, the yellow balls mark places where the PAHs (green) and the dust (red) have not yet separated. The superposition of green and red makes yellow.

So far, the volunteers have identified more than 900 of these compact, yellow features.  The multitude gives researchers plenty of chances to test their hypotheses and learn more about the way stars form.

Meanwhile, citizen scientists continue to scan Spitzer’s images for new finds. Green bubbles.  Red cores.  Yellow balls.  What’s next?  You could be the one who makes the next big discovery.  To get involved, go to zooniverse.org and click on “The Milky Way Project.”

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The Moon Was A First Step, Mars Will Test Our Capabilities, But Europa Is The Prize

The icy moon Europa is perhaps the most tantalising destination in our solar system. Scientists have been trying for years to kickstart a mission to Jupiter’s most enigmatic moon, with very Earth-like concerns over costs keeping missions grounded until now.

The European Space Agency’s ambitious mission to Jupiter, JUICE, will visit its fire-and-ice moons – volcanic Io, icy Europa, giant Ganymede, and cratered Callisto – in the 2030s. But it will only provide a glimpse of Europa’s surface from a couple of close flybys. With the announcement of the NASA-led Europa Clipper mission, now it looks like a much closer inspection of Europa is on the cards.

It’s hard to overstate the excitement among planetary scientists, after so many years of waiting in the wings while all eyes were on Mars. This is truly a quest to understand what makes a world habitable.

A Watery World

Europa is the smallest and smoothest of the four Galilean moons. At 1,940 miles across, it is roughly a quarter of the size of Earth, composed of a mixture of ices and rocks. When the Galileo spacecraft flew over Europa in the 1990s, it uncovered evidence of a global sub-surface ocean: vast, deep, dark waters hidden beneath the ice crust.

The water doesn’t freeze completely because it’s constantly kneaded by powerful tidal forces as the moon orbits around Jupiter once every 3.5 days. What’s more, the ocean is believed to be in direct contact with the surface ices and the moon’s silicate mantle, which brings together all the necessary ingredients for a habitable environment: liquid water, a source of energy, and a source of minerals/nutrients. We know that life on Earth can exist in even the most extreme environmental conditions (for example, bacteria known asextremophiles), so maybe – just maybe – Europa’s hidden ocean could support life.

The Galilean moons of Jupiter: Io, Europa, Ganymede and Callisto. NASA

What To Look For

Neither JUICE nor Clipper will reach the surface or the ocean below – that’s too great a technological challenge for now. But if habitable conditions for life are discovered beyond Earth, particularly somewhere as far from the Sun as Jupiter and its moons, this could mean that habitable conditions are commonplace throughout our universe.

We must begin to explore Europa via orbital reconnaissance: to image and perform spectral analysis of the composition and geology of the surface, and the radiation, magnetic, electric and plasma fields that sweep across it. With ice penetrating radar we can probe through the icy crust, even as far as the hidden ocean to understand the forces that shape this icy world.

Europa’s ‘chaos terrain’, caused by repeated freezing and melting. NASA

Europa’s fractured and cracked surface is geologically quite young, and relatively crater-free. The structures that the Galileo probe observed from orbit suggest freeze-melt processes that trap icy burgs into frozen seas, creating the scarred patterns known aschaos terrain. Dark parallel ridges criss-cross the bright planes, possibly due to tectonics or other geologic processes.

Most surprising was Hubble’s observations in 2012, which showed evidence of huge plumes or geysers erupting tens of kilometres over Europa’s south pole, potentially contributing to a very thin atmosphere. If we could directly sample those plumes we might just get a glimpse of the composition of the deep ocean.

Sooner Rather Than Later

So for all these reasons and more, Europa remains the highest priority target for a future mission. That there are two missions to the Jupiter system stems from years of study within NASA and ESA. At one point a joint mission, the Europa-Jupiter System Mission, was planned but was not taken forward due to funding constraints.

The Jupiter Icy Moon Explorer, JUICE, and its instruments. ESA

Today, JUICE is full-steam ahead, the project having passed through a full study and definition phase towards now building the spacecraft. If all goes to plan it would launch in 2022 and reach Jupiter in 2030. After two years of multiple fly-bys exploring Jupiter, its moons, rings and magnetosphere, it will become humankind’s first orbiter of an icy moon, targeting Ganymede in late 2032. If NASA’s recently announced funding is confirmed Europa Clipper may proceed even faster, using a new rocket (the Space Launch System) to propel it towards Europa in only a few years, potentially arriving just before or even at the same time as JUICE.

Clipper will conduct multiple flybys of Europa (maybe 45 or more over three years) without entering orbit directly, but will provide the high-resolution reconnaissance necessary to ultimately choose a landing site for some future robotic explorer. Although that future landing mission is beyond the funding horizon right now, it’s exciting to think that we’ll one day see images from that icy and harsh environment, with Jupiter suspended in the black skies above.


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26 Pictures Will Make You Re-Evaluate Your Entire Existence

. This is the Earth! This is where you live.

This is the Earth! This is where you live.

NASA Goddard Space Flight Center Image / Via visibleearth.nasa.gov

2. And this is where you live in your neighborhood, the solar system.

And this is where you live in your neighborhood, the solar system.

3. Here’s the distance, to scale, between the Earth and the moon. Doesn’t look too far, does it?

Here's the distance, to scale, between the Earth and the moon. Doesn't look too far, does it?

4. THINK AGAIN. Inside that distance you can fit every planet in our solar system, nice and neatly.

THINK AGAIN. Inside that distance you can fit every planet in our solar system, nice and neatly.

PerplexingPotato / Via reddit.com

5. But let’s talk about planets. That little green smudge is North America on Jupiter.

But let's talk about planets. That little green smudge is North America on Jupiter.

NASA / John Brady / Via astronomycentral.co.uk

6. And here’s the size of Earth (well, six Earths) compared with Saturn:

And here's the size of Earth (well, six Earths) compared with Saturn:

NASA / John Brady / Via astronomycentral.co.uk

7. And just for good measure, here’s what Saturn’s rings would look like if they were around Earth:

And just for good measure, here's what Saturn's rings would look like if they were around Earth:

Ron Miller / Via io9.com

8. This right here is a comet. We just landed a probe on one of those bad boys. Here’s what one looks like compared with Los Angeles:

This right here is a comet. We just landed a probe on one of those bad boys. Here's what one looks like compared with Los Angeles:

Matt Wang / Via mentalfloss.com

9. But that’s nothing compared to our sun. Just remember:

But that's nothing compared to our sun. Just remember:

10. Here’s you from the moon:

Here's you from the moon:

NASA

11. Here’s you from Mars:

Here's you from Mars:

NASA

12. Here’s you from just behind Saturn’s rings:

Here's you from just behind Saturn's rings:

NASA

13. And here’s you from just beyond Neptune, 4 billion miles away.

And here's you from just beyond Neptune, 4 billion miles away.

NASA

To paraphrase Carl Sagan, everyone and everything you have ever known exists on that little speck.

14. Let’s step back a bit. Here’s the size of Earth compared with the size of our sun. Terrifying, right?

Let's step back a bit. Here's the size of Earth compared with the size of our sun. Terrifying, right?

John Brady / Via astronomycentral.co.uk

The sun doesn’t even fit in the image.

15. And here’s that same Sun from the surface of Mars:

And here's that same Sun from the surface of Mars:

NASA

16. But that’s nothing. Again, as Carl once mused, there are more stars in space than there are grains of sand on every beach on Earth:

But that's nothing. Again, as Carl once mused, there are more stars in space than there are grains of sand on every beach on Earth:

17. Which means that there are ones much, much bigger than little wimpy sun. Just look at how tiny and insignificant our sun is:

Which means that there are ones much, much bigger than little wimpy sun. Just look at how tiny and insignificant our sun is:

Our sun probably gets its lunch money stolen.

18. Here’s another look. The biggest star, VY Canis Majoris, is 1,000,000,000 times bigger than our sun:

26 Pictures Will Make You Re-Evaluate Your Entire Existence

………

19. But none of those compares to the size of a galaxy. In fact, if you shrunk the Sun down to the size of a white blood cell and shrunk the Milky Way Galaxy down using the same scale, the Milky Way would be the size of the United States:

But none of those compares to the size of a galaxy. In fact, if you shrunk the Sun down to the size of a white blood cell and shrunk the Milky Way Galaxy down using the same scale, the Milky Way would be the size of the United States:

20. That’s because the Milky Way Galaxy is huge. This is where you live inside there:

That's because the Milky Way Galaxy is huge. This is where you live inside there:

21. But this is all you ever see:

But this is all you ever see:

(That’s not a picture of the Milky Way, but you get the idea.)

22. But even our galaxy is a little runt compared with some others. Here’s the Milky Way compared to IC 1011, 350 million light years away from Earth:

But even our galaxy is a little runt compared with some others. Here's the Milky Way compared to IC 1011, 350 million light years away from Earth:

Just THINK about all that could be inside there.

23. But let’s think bigger. In JUST this picture taken by the Hubble telescope, there are thousands and thousands of galaxies, each containing millions of stars, each with their own planets.

But let's think bigger. In JUST this picture taken by the Hubble telescope, there are thousands and thousands of galaxies, each containing millions of stars, each with their own planets.

24. Here’s one of the galaxies pictured, UDF 423. This galaxy is 10 BILLION light years away. When you look at this picture, you are looking billions of years into the past.

Here's one of the galaxies pictured, UDF 423. This galaxy is 10 BILLION light years away. When you look at this picture, you are looking billions of years into the past.

Some of the other galaxies are thought to have formed only a few hundred million years AFTER the Big Bang.

25. And just keep this in mind — that’s a picture of a very small, small part of the universe. It’s just an insignificant fraction of the night sky.

And just keep this in mind — that's a picture of a very small, small part of the universe. It's just an insignificant fraction of the night sky.

26. And, you know, it’s pretty safe to assume that there are some black holes out there. Here’s the size of a black hole compared with Earth’s orbit, just to terrify you:

And, you know, it's pretty safe to assume that there are some black holes out there. Here's the size of a black hole compared with Earth's orbit, just to terrify you:

D. Benningfield/K. Gebhardt/StarDate / Via mcdonaldobservatory.org

So if you’re ever feeling upset about your favorite show being canceled or the fact that they play Christmas music way too early — just remember…

This is your home.

This is your home.

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

This is what happens when you zoom out from your home to your solar system.

This is what happens when you zoom out from your home to your solar system.

And this is what happens when you zoom out farther…

And this is what happens when you zoom out farther...

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

And farther…

And farther...

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

Keep going…

Keep going...

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

Just a little bit farther…

Just a little bit farther...

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

Almost there…

Almost there...

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons

And here it is. Here’s everything in the observable universe, and here’s your place in it. Just a tiny little ant in a giant jar.

And here it is. Here's everything in the observable universe, and here's your place in it. Just a tiny little ant in a giant jar.

By Andrew Z. Colvin (Own work) [CC-BY-SA-3.0 (creativecommons.org) or GFDL (gnu.org)], via Wikimedia Commons


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20 Things You Didn’t Know About… Galaxies

galaxy

The Milky Way rotates at 560,000 miles per hour, and makes a full revolution every 200 million years.

 1. Eighteenth-century philosopher Immanuel Kant was one of the first people to theorize that the Milky Way was not the only galaxy in the universe. Kant coined the term island universe to describe a galaxy.

2. Astronomers now estimate that there are 100 billion galaxies in the observable universe.

3. One of the earliest uses of the English term Milky Way was in Geoffrey Chaucer’s 14th-century poem “The House of Fame.” He likened the galaxy to a celestial roadway.

4. While we’re talking road trips: Due to the expansion of the universe, all other galaxies are receding from our own. Galaxies farther from the Milky Way are speeding away faster than those nearby.

5. Some of the galaxies receding from the Milky Way are ellipsoidal, like footballs. Galaxies can also be thin and flat with tentacle-like arms — just like the Milky Way.

6. Galaxies come in irregular shapes, too, including many dwarf galaxies. These galaxies, the smallest in the universe, contain only a few hundred or a few thousand stars (compared with 100 billion stars in the Milky Way).

7. You’ll often find dwarf galaxies clustered around larger galaxies.

8. Dwarf galaxies frequently lose their stars to their larger neighbors via gravity. The stars stream across the sky as the dwarf galaxies are ripped apart. Alas, you can’t see it with the naked eye.

9. You also can’t see the enormous black hole lurking in the center of the Milky Way, though if you’ve ever looked at the constellation Sagittarius, the archer, you’ve looked in the right direction.

10. Most galaxies have a black hole at the center, and astronomers have found the mass is consistently about 1/1000th the mass of the host galaxy.

11. Two of the closest galaxies to the Milky Way — the Small Magellanic Cloud and the Large Magellanic Cloud — may not have black holes. Or, because both are low-mass galaxies, their central black holes may be too small to detect.

12. Every galaxy does have dust, though. Produced by stars, the dust causes light to look redder than it really is when observed visually, which can make it difficult for astronomers studying properties of stars.

13. That dust can really travel, too. Some galaxies drive galactic winds, expelling dust and gas at hundreds of kilometers per second into the intergalactic medium, the space between galaxies.

14. These winds are caused by starlight exerting pressure on the dust and gas; the fastest galactic winds are in distant galaxies that are forming stars more rapidly than the Milky Way.

15. The Milky Way rotates at about 250 kilometers per second (about 560,000 mph) and completes a full revolution about every 200 million years.

16. One galactic revolution ago, dinosaurs ruled the Earth.

17. Galaxies rotate faster than predicted based on the gravity of their stars alone. Astronomers infer that the extra gravitational force is coming from dark matter, which does not emit or reflect light.
18. Dark matter aside, galaxies are mostly empty space. If the stars within galaxies were shrunk to the size of oranges, they would be separated by 4,800 kilometers (3,000 miles).

19. If galaxies were shrunk to the size of apples, neighboring galaxies would only be a few meters apart. The relative proximity of galaxies means that galaxies occasionally merge.

20. In about 4 billion years, the Milky Way will merge with the Andromeda galaxy. The result of the merging process — which will take at least a hundred million years — will be an ellipsoidal galaxy nicknamed “Milkomeda.”


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Largest ever yellow star is 1300 times bigger than sun

A monster version of our sun has been found, the largest known member of the family of yellow stars to which our sun belongs.

The whopper sun emits light in similar wavelengths as our sun but its diameter is over 1300 times larger. That means it would engulf all the planets between Mercury and Jupiter if placed at the centre of our solar system. The star’s size also means it is touching its smaller, companion star (see diagram, below).

(Source: ESO)

Dubbed HR 5171 A, the star is located in the constellation Centaurus around 12,000 light years from Earth. It was already known to be a hypergiant, the largest class of stars, but its exact size hadn’t been well studied.

Now a team led by Oliver Chesneau of the Côte d’Azur Observatory in Nice, France, has taken a closer look with the Very Large Telescope in Atacama, Chile. They report that it is twice as large as expected.

It still isn’t the largest star we know about – that crown goes to UY Scuti, which is around 1700 times larger than our sun. But UY Scuti is in a different stage of stellar evolution and so belongs to a different family of stars called red stars.

Peanut sun

Both red and yellow stars can be hypergiants, but yellow hypergiants were previously thought to be at most 700 times the size of the sun. The new measurement of HR 5171 A shows they can be much bigger. HR 5171 A is 50 per cent larger than the red hypergiant Betelgeuse, which is located in the constellation Orion and is the ninth brightest star in the night sky.

Another surprise for Chesneau’s team was the discovery that HR 5171 A has a little brother. Previous observations suggested the star varied in brightness. Now the team has shown that this is due to a companion star that is around one third its size.

The two stars orbit each other, forming a binary system. However, though their centres are separated by more than the distance between our sun and Saturn, HR 5171 A is so large that the two are touching, forming a continuous peanut-shaped structure. Guess this star system ain’t big enough for two.