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Prof Claudia de Rham’s ‘massive gravity’ theory could explain why universe expansion is accelerating Cosmologists don’t enter their profession to tackle the easy questions, but there is one paradox that has reached staggering proportions. Since the big bang, the universe has been expanding, but the known laws of physics suggest that the inward tug of gravity should be slowing down this expansion. In reality, though, the universe is ballooning at an accelerating rate. Scientists have come up with a name – dark energy – for the mysterious agent that is allowing the cosmos to expand so rapidly and which is...

The Abell 85 galaxy cluster, which is home to a black hole of 40 billion solar masses Mathias Kluge/USM/MPE ===================================================================== Astronomers from the Max Planck Institute for Extraterrestrial Physics and at the University Observatory Munich have found the largest known black hole in our galactic neighborhood using direct mass measurements. Located 700 million light-years from Earth in the Abell 85 cluster of galaxies in the constellation of Cetus, it has a mass 40 billion times that of the Sun. Ever since the existence of the first black hole was confirmed in 1971, they have gone from being a mathematical curiosity...

Three supermassive black holes found lurking in one galaxy NGC 6240 is a well-studied example of a galaxy merger. But the discovery that it hides three supermassive black holes makes it a stunning example of a galaxy formed through a triple merger. By Alison Klesman  |  Published: Friday, November 22, 2019 RELATED TOPICS: BLACK HOLES | GALAXIES The strange galaxy NGC 6240 is an ultra-rare example of a galaxy harboring three supermassive black holes near its core. Astronomers already knew of the galaxy's active, northern black hole (N), but thanks to cutting-edge 3D-mapping techniques, they've now identified two more —...

Dark Matter Still Missing After Many Decades ... "Big Bang theory in trouble". November 22, 2019 | Jerry Bergman All the proposed candidates for mysterious, unknown stuff have failed to materialize, putting Big Bang theory in trouble. by Jerry Bergman, PhD The cover story of the November 16-22 New Scientist announced prominently on the cover: “DARK MATTER: We still haven’t found it. Our theories are falling apart. Is it time to rethink the universe?” [1] Dan Hooper, author of the cover story, is worried, because Dark Matter theory is a necessary support for the Big Bang. Thus, the Big Bang...

A MYSTERIOUS supermassive black hole in a distant galaxy is spitting high energy particles after being fed by an object that has never been seen before. The baffling phenomenon has put existing theoretical models on their head, and astrophysicists are puzzled as to what is creating such a regular excretion of material from within the bowels of this supermassive black hole. According to the paper titled, 'Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus', the energy erupts from the black hole every nine hours and last for one hour and it's that precision which has baffled scientists.

American space agency, the NASA had recently observed flares of X-rays from a black hole, which goes against the conventional notion that they are compact particles with such huge gravity that even light can't escape. Last month NASA announced that two of its space telescopes caught a huge burst of X-ray spewing out of a super massive black hole. These flairs appeared to be be triggered by the eruption of a charged particle from the black hole, which according to conventional belief doesn't let anything out. The latest findings are in accordance with the theory of Indian astrophysicist Abhas Mitra...

After the first-ever image of a black hole confirmed theories posited by Einstein, it's the late scientist Stephen Hawking's turn to have parts of his life's work vindicated. In a paper published in Nature, scientists say that have verified the scientist's namesake theory, Hawking Radiation, which hypothesized that black holes emit radiation from their surfaces due to a mix of different factors regarding quantum physics and gravity. To verify the theory, scientists at the Technion-Israel Institute of Technology turned to what sounds like mad science: creating their own black hole.

By 2013, the European Planck space telescope's detailed measurements of cosmic radiation seemed to have yielded the final answer: 13.8 billion years old. All that was left to do was to verify that number using independent observations of bright stars in other galaxies. Then came an unexpected turn of events. A few teams, including one led by Nobel laureate Adam Riess of the Space Telescope Science Institute in Baltimore, set out to make those observations. Instead of confirming Planck's measurements, they started getting a distinctly different result. At first, the common assumption was that Riess and the other galaxy-watchers had...

There's a "dark impactor" blasting holes in our galaxy. Stellar streams are lines of stars moving together across galaxies, often originating in smaller blobs of stars that collided with the galaxy in question. Under normal conditions, the stream should be more or less a single line, stretched out by our galaxy's gravity, she said in her presentation. Astronomers would expect a single gap in the stream, at the point where the original globular cluster was before its stars drifted away in two directions. But Bonaca showed that GD-1 has a second gap. And that gap has a ragged edge —...

Black holes are famous for their muscle: an intense gravitational pull known to gobble up entire stars and launch streams of matter into space at almost the speed of light. It turns out the reality may not live up to the hype. In a paper published today in the journal Science, University of Florida scientists have discovered these tears in the fabric of the universe have significantly weaker magnetic fields than previously thought. A 40-mile-wide black hole 8,000 light years from Earth named V404 Cygni yielded the first precise measurements of the magnetic field that surrounds the deepest wells of...

Acceleration as a function of radius in NGC 4455, one of the studied galaxies As fascinating as it is mysterious, dark matter is one of the greatest enigmas of astrophysics and cosmologyIt is thought to account for 90 percent of the matter in the universe, but its existence has been demonstrated only indirectly, and has recently been called into question New research conducted by SISSA removes the recent doubts on the presence of dark matter within galaxies, disproving the empirical relations in support of alternative theories. The study, published in the Astrophysical Journal, also offers new insights into understanding the...

Astronomers have been grappling with the mystery of dark matter for a long time, and I mean a looong time. The history of dark-matter investigations goes back at least to 1906, when physicist Henri Poincaré’s 1906 speculated about the amount of “matière obscure” in the Milky Way. Or really, it goes to back to 1846 and the first successful detection of dark matter: the discovery of the planet Neptune, whose existence had been inferred by its gravitational pull well before it was actually observed. Since then, scientists have identified many different dark components in space: collapsed stars, interstellar dust, hot...

Scientists have finally been able to accurately calculate the weight of the Milky Way, overcoming the difficult hurdle of measuring dark matter, the European Space Agency (ESA) announced Thursday. After years of struggling to estimate the size of our galaxy, astronomers with NASA and the ESA used data from the Hubble Space Telescope and the ESA’s Gaia mission to determine the Milky Way weighs about 1.5 trillion solar masses within a radius of 129,000 light years from the center. Because dark matter makes up about 90 percent of the galaxy, estimates of the Milky Way’s weight have differed widely in...

An invisible force is having an effect on our Universe. We can't see it, and we can't detect it - but we can observe how it interacts gravitationally with the things we can see and detect, such as light. Now an international team of astronomers has used one of the world's most powerful telescopes to analyse that effect across 10 million galaxies in the context of Einstein's general relativity. The result? The most comprehensive map of dark matter across the history of the Universe to date. ... "If further data shows we're definitely right, then it suggests something is missing...

Late in 2018, the gravitational wave observatory, LIGO, announced that they had detected the most distant and massive source of ripples of spacetime ever monitored: waves triggered by pairs of black holes colliding in deep space. Only since 2015 have we been able to observe these invisible astronomical bodies, which can be detected only by their gravitational attraction. The history of our hunt for these enigmatic objects traces back to the 18th century, but the crucial phase took place in a suitably dark period of human history – World War II. The concept of a body that would trap light,...

Black holes are among the most mysterious places in the universe; locations where the very fabric of space and time are warped so badly that not even light can escape from them. According to Einstein's theory of general relativity, at their center lies a singularity, a place where the mass of many stars is crushed into a volume with exactly zero size. However, two recent physics papers, published on Dec.10 in the journals Physical Review Letters and Physical Review D, respectively, may make scientists reconsider what we think we know about black holes. Black holes might not last forever, and...

Scientists at the University of Oxford may have solved one of the biggest questions in modern physics, with a new paper unifying dark matter and dark energy into a single phenomenon: a fluid which possesses 'negative mass." If you were to push a negative mass, it would accelerate towards you. This astonishing new theory may also prove right a prediction that Einstein made 100 years ago. Our current, widely recognised model of the Universe, called LambdaCDM, tells us nothing about what dark matter and dark energy are like physically. We only know about them because of the gravitational effects they...

Broderick's work builds on earlier research by two teams that studied the galactic center of the Milky Way in near-infrared. This included the work of Reinhard Genzel, an astronomer from the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, as well as researchers Andrea Ghez and Mark Morris of University of California, Los Angeles. At the time, their work revealed that the center of the Milky Way wasn't steady, but instead would drastically brighten about once a day for about 30 or 40 minutes, Broderick said. Researchers think supermassive black holes exist at the center of most, if not...

Circling our galaxy is a stealthy giant. Astronomers have discovered a dwarf galaxy, called Antlia 2, that is one-third the size of the Milky Way itself. As big as the Large Magellanic Cloud, the galaxy’s largest companion, Antlia 2 eluded detection until now because it is 10,000 times fainter. Such a strange beast challenges models of galaxy formation and dark matter, the unseen stuff that helps pull galaxies together. “It’s a very odd object and kind of exciting because we don’t know yet how to interpret all of its properties,” says Andrey Kravtsov of The University of Chicago in Illinois,...

Let's talk about dark energy. We've known for about 20 years that the expansion of our universe is accelerating; every day, our cosmos grows bigger and bigger, doing so faster and faster. It's a subtle effect, and it takes extensive and deep cosmological surveys and studies for scientists to notice it. But multiple independent lines of evidence all point to the same conclusion: accelerating expansion. Astronomers quickly cooked up a cool name for that accelerated expansion: dark energy. But now we’re left with the much harder job of finding a culprit — what's causing it? A universal mistake We use...