Keyword: haltonarp
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Astronomer Mark Lacy and colleagues used the Atacama Large Millimeter Array in Chile to observe the universe’s first light, and found evidence of gusts flowing from a type of black hole called a quasar. The wind extends about 228,000 light-years away from the galaxy that surrounds the quasar. Previously, astronomers had seen signs of these winds only about 3,000 light-years from their galaxies.The result, published November 12 at arXiv.org, could help resolve questions about how black holes can grow with their galaxies, or shut galaxies down for good.Black holes are best known for gravitationally gobbling everything that veers too close....
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A glob of material the size of Earth is getting sucked into a black hole at nearly one-third the speed of light, a new study reports. The speed of light in a vacuum is 186,282 miles (299,792 kilometers) per second, and, according to Einstein's theory of special relativity, that's the top speed for anything traveling in our universe. So, something zipping at a third the speed of light is moving nearly 56,000 miles (90,000 km) per second — fast enough to circle Earth twice in that brief time. The newly observed infall event occurred in the galaxy PG211+143, which is...
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Radio observations using a combination of NSF’s Very Long Baseline Array, the Karl G. Jansky Very Large Array and the Robert C. Byrd Green Bank Telescope have revealed that a fast-moving jet of particles broke out into interstellar space after a pair of neutron stars merged in NGC 4993, a lenticular galaxy approximately 130 million light-years from Earth.-snip- Called GW170817, the merger of two neutron stars sent gravitational waves rippling through space. It was the first event ever to be detected both by gravitational waves and electromagnetic waves, including gamma rays, X-rays, visible light, and radio waves.The aftermath of the...
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It's been nearly a century since scientists first theorized that the Universe was expanding, and that the farther away a galaxy was from us, the faster it appears to recede. This isn't because galaxies are physically moving away from us, but rather because the Universe is full of gravitationally-bound objects, and the fabric of space that those objects reside in is expanding. But this picture, which held sway from the 1920s onward, has been recently revised. It's been only 20 years since we first realized that this expansion was speeding up, and that as time goes on, individual galaxies will...
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MIT scientists have uncovered a sprawling new galaxy cluster hiding in plain sight. The cluster, which sits a mere 2.4 billion light years from Earth, is made up of hundreds of individual galaxies and surrounds an extremely active supermassive black hole, or quasar. The central quasar goes by the name PKS1353-341 and is intensely bright — so bright that for decades astronomers observing it in the night sky have assumed that the quasar was quite alone in its corner of the universe, shining out as a solitary light source from the center of a single galaxy. But as the MIT...
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A supermassive black hole has been found at the center of a tiny galaxy, a rare find. What makes the discovery even more unique is that it has been located in an ultracompact dwarf galaxy, stunning researchers. The findings, published in the Monthly Notices of the Royal Astronomical Society, note that the galaxy Fornax UCD3 is part of a set called ultracompact dwarfs (UCDs), a very rare set of galaxies. "We have discovered a supermassive black hole in the center of Fornax UCD3," said the study's lead author, Anton Afanasiev, in a statement. "The black hole mass is 3.5 million...
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Next time you eat a blueberry (or chocolate chip) muffin consider what happened to the blueberries in the batter as it was baked. The blueberries started off all squished together, but as the muffin expanded they started to move away from each other. If you could sit on one blueberry you would see all the others moving away from you, but the same would be true for any blueberry you chose. In this sense galaxies are a lot like blueberries. Since the Big Bang, the universe has been expanding. The strange fact is that there is no single place from...
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Our universe's rate of expansion keeps getting stranger. New data continues to show a discrepancy in how fast the universe expands in nearby realms and more distant locations. The study's researchers said this "tension" could mean we need to revise our understanding of the physics structuring the universe, which could include exotic elements such as dark matter and dark energy. New measurements from the Hubble Space Telescope and the Gaia space telescope together showed that the rate of expansion nearby is 45.6 miles per second per megaparsec. This means that for every 3.3 million light-years a galaxy is farther away from...
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At 13.8 billion years ago, our entire observable universe was the size of a peach and had a temperature of over a trillion degrees. That's a pretty simple, but very bold statement to make, and it's not a statement that's made lightly or easily. Indeed, even a hundred years ago, it would've sounded downright preposterous, but here we are, saying it like it's no big deal. But as with anything in science, simple statements like this are built from mountains of multiple independent lines of evidence that all point toward the same conclusion — in this case, the Big Bang,...
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1. Starlight bends — but how much? Einstein performed a series of calculations to determine the size of the predicted shift but initially muffed the effort, arriving at a number that was half the correct value. Had the astronomers managed to test this number in their initial eclipse-viewing efforts, their observations wouldn’t have matched his prediction. But their attempts were stymied by weather in 1912 and by war in 1914. By the time they made the necessary observation, in the spring of 1919, Einstein had corrected his blunder — and astronomers saw exactly the shift that he had predicted. 2....
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(The Hubble Space Telescope captured this image of ancient and brilliant quasar 3C 273, which resides in a giant elliptical galaxy in the constellation of Virgo. Its light has taken some 2.5 billion years to reach us. Despite this great distance, it is still one of the closest quasars to our home. It was the first quasar ever to be identified, and was discovered in the early 1960s by astronomer Allan Sandage.) Shining so brightly that they eclipse the ancient galaxies that contain them, quasars are distant objects powered by black holes a billion times as massive as our...
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The most massive galaxies in our neighbourhood formed their stars billions of years ago, early in the history of the universe. At the present day, they produce very few new stars. Astronomers have long believed that is because they contain very little gas – a key ingredient necessary to produce stars. But our new study, published in Nature Astronomy, is now challenging this long held view. Through probing the extreme environments of faraway massive galaxies, we can learn not only about their evolution and the history of the universe, but most importantly about the fundamental processes regulating the formation of...
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Observations of a trio of dead stars have confirmed that a foundation of Einstein’s gravitational theory holds even for ultradense objects with strong gravitational fields. The complex orbital dance of the three former stars conforms to a rule known as the strong equivalence principle, researchers reported January 10 at a meeting of the American Astronomical Society. That agreement limits theories that predict Einstein’s theory, general relativity, should fail at some level. According to general relativity, an object’s composition has no impact on how gravity pulls on it: Earth’s gravity accelerates a sphere of iron at the same rate as a...
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How Can We Save The Sun? Published: 23 Sep , 2016 by Fraser Cain Video Remember the movie Sunshine, where astronomers learn that the Sun is dying? So a plucky team of astronauts take a nuclear bomb to the Sun, and try to jump-start it with a massive explosion. Yeah, there’s so much wrong in that movie that I don’t know where to start. So I just won’t.Seriously, a nuclear bomb to cure a dying Sun?Here’s the thing, the Sun is actually dying. It’s just that it’s going to take about another 5 billion years to run of fuel in...
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When astronomers discovered a strange pattern of light near a distant star called KIC 8462852 back in October, it was like nothing anyone had observed before. When a planet passes in front of star, the star’s brightness usually dips by around 1 percent, but KIC 8462852 has been experiencing dips of up to 22 percent, suggesting that something huge is zooming past. And now a second star with strange dips in brightness has been identified. Named EPIC 204278916, the star is estimated to be about the size of our Sun in diameter, but has only half its mass. It was...
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Remember Tabby’s Star? It’s the star that astronomer Tabetha Boyajian – who reported its strangeness in a Ted Talk in February, 2016 – famously called “the most mysterious star in the galaxy.” It’s mysterious because astronomers have never seen another star do what this star does. One explanation for the strange dimming of its light is that the star has an alien-built megastructure – a Dyson sphere – around it. Does it? Will we ever know for sure? Those are unanswered questions, but, while you’re pondering it, here’s the latest on this wonderful star. On August 3, 2016, two astronomers...
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The more scientists learn about "Tabby's Star," the more mysterious the bizarre object gets. Newly analyzed observations by NASA's planet-hunting Kepler space telescope show that the star KIC 8462852 — whose occasional, dramatic dips in brightness still have astronomers scratching their heads — has also dimmed overall during the last few years. ... KIC 8462852 hit the headlines last September, when a team of astronomers led by Tabetha Boyajian of Yale University announced that the star had dimmed dramatically several times over the past few years — in one case, by a whopping 22 percent. These brightness dips are too...
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The bizarre long-term dimming of Tabby's star — also known as Boyajian's star, or, more formally, KIC 8462852 — is likely caused by dust, not a giant network of solar panels or any other "megastructure" built by advanced aliens, a new study suggests. Astronomers came to this conclusion after noticing that this dimming was more pronounced in ultraviolet (UV) than infrared light. Any object bigger than a dust grain would cause uniform dimming across all wavelengths, study team members said. [13 Ways to Hunt Intelligent Aliens] "This pretty much rules out the alien megastructure theory, as that could not explain...
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Explanation: A remarkable telescopic composition in yellow and blue, this scene features a trio of interacting galaxies almost 90 million light-years away, toward the constellation Virgo. On the right, two, spiky, foreground Milky Way stars echo the trio galaxy hues, a reminder that stars in our own galaxy are like those in the distant island universes. With sweeping spiral arms and obscuring dust lanes, NGC 5566 is enormous, about 150,000 light-years across. Just above it lies small, blue NGC 5569. Near center, the third galaxy, NGC 5560, is multicolored and apparently stretched and distorted by its interaction with NGC 5566....
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Every now and then, a distant star called KIC 8462852 dims by as much as 20 percent. That's huge. Even a passing planet as big as Jupiter would only block about 1 percent of the star's light. Ruling out a planet, scientists have no idea what could be eclipsing the star (which is informally known as 'Tabby's Star'). The leading hypothesis is a family of really big comets, but that doesn't quite fit. Astronomer Jason Wright pointed out that the light patterns are consistent with what we'd expect if aliens had built a Dyson swarm of solar collectors around the...
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