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This doesn't look much like a galaxy, but it is in fact the Large Magellanic Cloud, one of the biggest satellite galaxies of our Milky Way. This awesome infrared image reveals the real look of this galaxy like never before. More »
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Our Milky Way is just a spiral galaxy, but NGC 1232 here is a grand spiral galaxy, its diameter twice as long as ours. Everything is bigger in NGC 1232, including the giant satellite galaxy warping it out of shape. More »
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Although dark matter's exact nature is still unknown, what we do know is that the amount of gravity in the universe is greater than the amount of visible matter that it corresponds to. This anomaly could be explained by some unseen source of extra mass, which provides the additional gravity that helps hold galaxies together. And the missing matter behind this extra mass has been dubbed dark matter. More »
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This is AB7, a binary star system found in one of the nearby Magellanic Cloud galaxies. The two stars are constantly venting massive amounts of stellar material. That process is heating up one of the stars to absolutely unimaginable temperatures. More »
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In the February 1952 issue of Galaxy magazine, Robert Heinlein offered his verdict on the conclusion of the twentieth century. He would later revisit these predictions in the 1966 short story collection The Worlds of Robert A. Heinlein and discuss the challenges of predicting the future. Here's what the author gathered, six decades ago: More »
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Believe it or not, that blue horseshoe-shaped structure around that bright star is an entire galaxy, although it doesn't really look anything like that. Its incredible twisted shape is a mirage created by a strange phenomenon called gravitational lensing. More »
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Unfortunately, you won't be able to order a drink there. It's actually a gigantic, bar-shaped formation of stars found right at the center of our home galaxy. And it rotates like nothing else in the Milky Way. More »
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In the first billion years after the Big Bang, the universe was a smaller, emptier place, without the huge galaxies that dominate today. But there were already supermassive black holes that had grown shockingly huge by gorging themselves on gas. More »
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Four newly discovered galaxies are so dim, so dusty, so impossibly distant that even the Hubble telescope couldn't spot them. But that's not all: these galaxies are so insanely red that astronomers are declaring them a new "species" of galaxy. More »
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Centaurus A is an active galaxy, meaning it gives off extraordinary amounts of radiation, most likely the result of a supermassive black hole. Somewhere inside these gas clouds and dust lanes, that black hole is creating unimaginable cosmic chaos. More »
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Messier 83 is one of the closest spiral galaxies in the night sky, located just 12 million light-years from Earth. Its unique properties have earned it two of the more evocative galactic nicknames: the Southern Pinwheel and the Thousand-Ruby Galaxy. More »
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The image up top is an artist's impression of a gamma-ray burst blasting through a pair of galaxies on its billion-year journey to Earth. These ancient, incredibly powerful explosions reveal the composition of early galaxies. It's not what we expected. More »
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That bright explosion of stars on the right is a globular star cluster, one of just 160 such clusters in the galaxy. It's making its big debut after long being hidden behind the dust of the center of the galaxy. More »
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Many galaxies have gigantic black holes located at their center, but we're not usually able to actually see just how gigantic they are. Supermassive black holes are shrouded in huge dust clouds...which might be essential for the development of life. More »
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The galaxy cluster at the center of this image has so much gravitational force that it warps and distorts our view of everything behind it. This photo offers a particularly dramatic example: look at that twisted galaxy on the right. More »
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Dark matter almost certainly exists - otherwise, galaxy clusters wouldn't have sufficient gravity to hold themselves together. It was hoped dwarf galaxies could confirm the leading dark matter theories. But a new study has drawn a big, frustrating blank. More »
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A basic fact of the universe is that space is a dark, black expanse that's only broken up by the lights of stars and galaxies. But that wasn't always the case — space was once a dense, opaque fog. More »
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Galaxy Arp 220, located 250 million light-years from Earth, is home to seven different supernova explosions all going on at the same time. We've never seen so many stars exploding simultaneously in the same galaxy. More »
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Colliding galaxies may be common, but cosmic cacophony on this scale is still unusual. What we have here are two galaxies merging together in your standard collision...and then a third galaxy sidling in, just to complete the intergalactic chaos. More »
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We didn't yet have the technology to notice, but Sagittarius A*, the supermassive black hole at the center of our galaxy, threw one hell of a tantrum a few hundred years ago. It's the only explanation for mysterious x-ray anomalies. More »
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The whole point of white dwarfs is that they're the remains of stars not big enough to go supernova. Or so we thought. Many of these stars are held together by their super-fast spins... and slowing down could mean an explosion. More »
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This image taken by NASA's Wise Satellite is in the infrared spectrum, meaning it can reveal the light that is normally hidden behind thick, dark clouds of gas. But some clouds are so dark that no light can get through. More »
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That green clump might not be much to look at, but it's one of the rarest sights in the cosmos: a Lyman-alpha blob. They're among the universe's biggest structures, and only now are we starting to understand how they work. More »
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Astrophysicists have been trying for nearly two decades to produce a model capable of simulating the genesis of a spiral galaxy — the class of flat, rotating disk galaxies to which our own Milky Way belongs. And now, they've finally done it. More »
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Actually (if you insist on being technical about it), astronomers refer to it as a "flocculent" spiral galaxy, but it means pretty much the same thing. Seriously, look it up. More »
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Many stars form in giant groups known as open clusters, which are crucial for the galaxy's development. There should be about 30,000 clusters in the Milky Way, but we've only ever found 2,500. Now, you can raise that number to 2,596. More »
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This breathtaking panorama combines the two hemispheres of the Milky Way galaxy into one. On top, we can see the northern stars from the Canary Islands, while on bottom we can see the southern sky from Chile's Atacama desert. More »
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In the prevailing view, elliptical galaxies are long-dead places, full of stars that are all at least seven to ten billion years old and without the gas needed to form new stars. The truth may not be that simple. More »
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Between those bizarre structures, the impossible colors up in the night sky, and the fact that this photo was apparently taken in the middle of a busy star cluster, how can this not be from some far distant alien world? More »
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This chaotic mess may look like a single galaxy. However, NGC 3314 is actually two distinct galaxies separated by millions of light-years that just happen to be perfectly arranged relative to Earth so that they look like one gigantic galaxy. More »
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The Milky Way is about 100,000 light-years in diameter, but that doesn't mean we're necessarily able to see everything our galaxy has to offer. The trouble comes from this thick nearby dust cloud, which blocks the stars behind it. More »
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Gravity forces galaxies that are relatively close together to form clusters, which in turn form superclusters between vast stretches of cosmic void. But now there's an even bigger level of organization...and we have no idea how to explain it. More »
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About two billion light-years from Earth, there's a huge jet of matter emanating from the core of galaxy 3C303. The jet carries a current of 10^18 amps, making it by far the highest electric current ever seen. More »
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This amazing image reveals the Great Carina Nebula, one of the most active star-forming regions in our galaxy. But it isn't just new stars that are being born in the nebula, as old stars are also dying in spectacular supernovas. More »
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You'd be forgiven for having that reaction to this photo of the Ames Monument, a pyramid in Wyoming built to commemorate the transcontinental railroad. But that strange, unearthly light is just the beginning of the weirdness on display here. More »
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This is the galaxy NGC 6744, located about 30 million light-years away. It just so happens that this galaxy looks pretty much exactly like what our own galaxy would look like...except this galaxy is twice as big as ours. More »
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The galaxy in this picture is Centaurus A, but it's being upstaged in its own cosmic neighborhood. Its central black hole is emitting jets that are a million light-years long...and this is our best look yet at this mysterious phenomenon. More »
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This star may not look like much, but in 1923 it changed our understanding of the universe forever. It showed us that the Milky Way wasn't a lonely island universe, but instead just one of billions and billions of galaxies. More »
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Here are three unsettling facts: Every galaxy has a black hole at its center; the black hole is spinning; and the black hole's spin is speeding up. More »
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Molecular windstorms are ripping through the universe at 10,000 times the speed of the most powerful Earth hurricane. These super-sized storms can strip galaxies of the raw materials needed to make new stars in just 100 million years. More »
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