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Black holes are powerful cosmic reactors. They supply the energy for quasars and other active galactic nuclei (AGNs). This is due to the interplay between matter and its enormous gravitational and magnetic forces. A black hole technically lacks a magnetic field, but the dense plasma surrounding it as an accretion disc does possess a magnetic field. As plasma spirals around a black hole, the charged particles inside it create an electrical current and magnetic field. The direction of plasma flow does not spontaneously vary, hence the magnetic field is likely rather stable. Imagine the researchers’ amazement when they discovered evidence...

In an incredible world first, astrophysicists have detected multiple planets in another galaxy, ranging from masses as small as the Moon to ones as great as Jupiter. Given how difficult it is to find exoplanets even within our Milky Way galaxy, this is no mean feat. Researchers at the University of Oklahoma achieved this thanks to clever use of gravitational microlensing. The technique, first predicted by Einstein's theory of general relativity, has been used to find exoplanets within Milky Way, and it's the only known way of finding the smallest and most distant planets, thousands of light-years from Earth. As...

Explanation: Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image. The central cloverleaf is rather light emitted from a background quasar. The gravitational field of the visible foreground galaxy breaks light from this distant quasar into four distinct images. The quasar must be properly aligned behind the center of a massive galaxy for a mirage like this to be evident. The general effect is known as gravitational lensing, and this specific case is known as the...

There are supermassive black holes. There are ultramassive black holes. How large can these strange objects grow? Well, there could be something even bigger than ultramassive: stupendously large black holes, according to the latest research. Such hypothetical black holes - larger than 100 billion times the mass of the Sun - have been explored in a new paper which names them SLABs, an acronym that stands for "Stupendously LArge Black holeS". "We already know that black holes exist over a vast range of masses, with a supermassive black hole of 4 million solar masses residing at the centre of our...

NASA scientists have spotted what they are calling a “halo” around Andromeda. The halo, which is more like a huge bloom of plasma, stretches 1.3 million light-years into space. That’s roughly halfway to our own galaxy, which is an impressive feat. We often think of galaxies as self-contained collections of stars, planets, and gasses, but that’s simply not the case. The effects of a galaxy extend far beyond their outer edge. In fact, the line between the edge of a galaxy and empty space is so blurred that there’s hardly a real “edge” at all. In the case of Andromeda,...

At the center of almost every galaxy in the universe is a supermassive black hole gobbling up incredible amounts of matter, and belching out incredible amounts of radiation. The biggest and hungriest of these gobblers — called quasars (or quasi-stellar objects, because they look deceptively like stars when seen through most telescopes) — are some of the most energetic objects in the universe. As infalling matter swirls around the quasar's maw at near-light-speed, that matter heats up and flies outward, propelled by the incredible force of its own radiation. All that intergalactic indigestion makes a quasar an awesome sight, capable...

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...

(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...

Scientists using NASA’s Hubble Space Telescope have discovered that the immense halo of gas enveloping the Andromeda galaxy, our nearest massive galactic neighbor, is about six times larger and 1,000 times more massive than previously measured. The dark, nearly invisible halo stretches about a million light-years from its host galaxy, halfway to our own Milky Way galaxy. This finding promises to tell astronomers more about the evolution and structure of majestic giant spirals, one of the most common types of galaxies in the universe. “Halos are the gaseous atmospheres of galaxies. The properties of these gaseous halos control the rate...

Scientists name new ‘object’ SDSS J0100+2802 and say it is 12.8bn light years from Earth and was formed just 900m years after the Big Bang *************************************************************A monster black hole powering “the brightest lighthouse in the distant universe” has been discovered that is 12bn times more massive than the sun, scientists have revealed.The extraordinary object is at the centre of a quasar - an intensely powerful galactic radiation source - with a million billion times the sun’s energy output.For years the nature of quasars, discovered in 1963, remained a mystery. Today scientists believe they are generated by matter heating up as...

VLT reveals alignments between supermassive black hole axes and large-scale structure New observations with ESO’s Very Large Telescope (VLT) in Chile have revealed alignments over the largest structures ever discovered in the Universe. A European research team has found that the rotation axes of the central supermassive black holes in a sample of quasars are parallel to each other over distances of billions of light-years. The team has also found that the rotation axes of these quasars tend to be aligned with the vast structures in the cosmic web in which they reside.See Full Size Photo Quasars are galaxies with...

Massive Quasar Cluster Refutes Core Cosmology Principle by Brian Thomas, M.S. * Astronomers recently found a distant collection of quasars. But those quasars shouldn’t exist. And while they certainly appear connected, they’re spread too far across space for standard secular models of the structure and origin of the universe to accommodate. “It is the largest structure ever seen in the entire universe,” according to astrophysicist Roger Clowes from the University of Central Lancashire.1 Clowes led a team of researchers, who published their discovery in The Monthly Notices of the Royal Astronomical Society,2 in analyzing data from the Sloan Digital Sky...

Astronomers have discovered the largest and oldest mass of water ever detected in the universe — a gigantic, 12-billion-year-old cloud harboring 140 trillion times more water than all of Earth's oceans combined. The cloud of water vapor surrounds a supermassive black hole called a quasar located 12 billion light-years from Earth. The discovery shows that water has been prevalent in the universe for nearly its entire existence, researchers said. "Because the light we are seeing left this quasar more than 12 billion years ago, we are seeing water that was present only some 1.6 billion years after the beginning of...

This false-color composite of the triple quasar system was made using a combination of Keck Observatory's and the European Very Large Telescope's visible and infrared data. S. G. Djorgovski and colleagues, Caltech, and EPFLOf all the known objects known in the universe, quasars probably deserves the most superlatives. These blazing cosmic beacons pack the energy of an entire galaxy’s worth of stars into a volume of space the size of our solar system. Until now, astronomers have found about 100,000 of these extraordinary objects, which are fueled by supermassive black holes devouring large clumps of matter. Most quasars are solitary...

New observations of galaxies reveal perplexing concentrations in certain directions, astronomers said today. Galaxies along the sight-lines toward distant explosive gamma-ray bursts appear to be four times as abundant as in the directions of quasars. Gamma-ray bursts are massive eruptions of dying stars. Quasars are constantly bright objects are thought to involve supermassive black holes surrounded by developing galaxies. There is no known reason why foreground galaxies should have any association with these background light sources, researchers said. "The result contradicts our basic concepts of cosmology, and we are struggling to explain it," said Jason X. Prochaska, associate professor of...

 As the author of these columns describing cutting edge physics and astronomy, I get quite a few letters and E-mail from readers who are more interested in ?over-the-edge physics and astronomy?.  One recurring theme is various alternatives to the standard model of Big Bang cosmology.  Perhaps the universe is not expanding; it?s just that light ?gets tired? on its path from far away and loses some of its energy.  Perhaps quasars are closer than we think, particularly since some of them appear to be linked to closer galaxies.  Perhaps relativity is wrong, and it?s the speed of light that is...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 December 15 A Network of Microlensing Caustics Credit & Copyright: Joachim Wambsganss (Ap. Inst. Potsdam) Explanation: A virtual sky map like this would be of interest to astronomers studying gravitational microlensing. In microlensing, the gravity of stars near the line of sight can act to magnify the light of background objects such as distant stars, or quasars. Nowhere is this magnification greater than near a gravitational lensing...