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The galaxy clusters Abell 0399 and Abell 0401 are some of the most massive objects in the universe. In a new study, researchers have discovered a 10-million-light-year-long bridge of radio waves (shown in blue in this composite image) linking them, and it’s doing crazy things to electrons. On the big roadmap of the universe, bustling clusters of galaxies are connected by long highways of plasma weaving around the wilderness of empty space. These interspace roadways are known as filaments, and they can stretch for hundreds of millions of light-years, populated only by dust, gas and busy electrons driving very close...

There’s a crisis brewing in the cosmos. Measurements over the past few years of the distances and velocities of faraway galaxies don’t agree with the increasingly controversial “standard model” of the cosmos that has prevailed for the past two decades. Astronomers think that a 9 percent discrepancy in the value of a long-sought number called the Hubble Constant, which describes how fast the universe is expanding, might be revealing something new and astounding about the universe. The cosmos has been expanding for 13.8 billion years and its present rate of expansion, known as the Hubble constant, gives the time elapsed...

Measurements of gravitational waves from approximately 50 binary neutron stars over the next decade will definitively resolve an intense debate about how quickly our universe is expanding, according to findings from an international team that includes University College London (UCL) and Flatiron Institute cosmologists. When neutron stars collide, they emit light and gravitational waves, as seen in this artist's illustration. By comparing the timing of the two emissions from many different neutron star mergers, researchers can measure how fast the universe is expanding. Credit: R. Hurt/Caltech-JPL The cosmos has been expanding for 13.8 billion years. Its present rate of expansion,...

Something isn't quite right in the universe. At least based on everything physicists know so far. Stars, galaxies, black holes and all the other celestial objects are hurtling away from each other ever faster over time. Past measurements in our local neighborhood of the universe find that the universe is exploding outward faster than it was in the beginning. That shouldn't be the case, based on scientists' best descriptor of the universe. If their measurements of a value known as the Hubble Constant are correct, it means that the current model is missing crucial new physics, such as unaccounted-for fundamental...

The light released from around the first massive black holes in the universe is so intense that it is able to reach telescopes across the entire expanse of the universe. Incredibly, the light from the most distant black holes (or quasars) has been traveling to us for more than 13 billion light years. However, we do not know how these monster black holes formed. New research led by researchers from Georgia Institute of Technology, Dublin City University, Michigan State University, the University of California at San Diego, the San Diego Supercomputer Center and IBM provides a new and extremely promising...

The question of how quickly the universe is expanding has been bugging astronomers for almost a century. Different studies keep coming up with different answers—which has some researchers wondering if they've overlooked a key mechanism in the machinery that drives the cosmos. Now, by pioneering a new way to measure how quickly the cosmos is expanding, a team led by UCLA astronomers has taken a step toward resolving the debate. The group's research is published today in Monthly Notices of the Royal Astronomical Society.At the heart of the dispute is the Hubble constant, a number that relates distances to the...

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....

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...

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...

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...

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...

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...

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...

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...

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,...

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....

(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...

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...

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...

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...