A supernova-like explosion dubbed the Camel appears to be the result of a newborn black hole eating a star from the inside out.
Category: cosmology – Page 289
How can you possibly use simulations to reconstruct the history of the entire universe using only a small sample of galaxy observations? Through big data, that’s how.
Theoretically, we understand a lot of the physics of the history and evolution of the universe. We know that the universe used to be a lot smaller, denser, and hotter in the past. We know that its expansion is accelerating today. We know that the universe is made of very different things, including galaxies (which we can see) and dark matter (which we can’t).
We know that the largest structures in the universe have evolved slowly over time, starting as just small seeds and building up over billions of years through gravitational attraction.
With the help of the European Southern Observatory’s Very Large Telescope (ESO ’s VLT), astronomers have discovered and studied in detail the most distant source of radio emission known to date. The source is a “radio-loud” quasar — a bright object with powerful jets emitting at radio wavelengths — that is so far away its light has taken 13 billion years to reach us. The discovery could provide important clues to help astronomers understand the early Universe.
Quasars are very bright objects that lie at the center of some galaxies and are powered by supermassive black holes. As the black hole consumes the surrounding gas, energy is released, allowing astronomers to spot them even when they are very far away.
The newly discovered quasar, nicknamed P172+18, is so distant that light from it has traveled for about 13 billion years to reach us: we see it as it was when the Universe was just around 780 million years old. While more distant quasars have been discovered, this is the first time astronomers have been able to identify the telltale signatures of radio jets in a quasar this early on in the history of the Universe. Only about 10% of quasars — which astronomers classify as “radio-loud” — have jets, which shine brightly at radio frequencies.[1].
Astronomers using data from the eROSITA X-ray telescope aboard the Spektrum-Roentgen-Gamma (SRG) observatory have detected the largest supernova remnant ever discovered with X-rays.
They may not be black or holes.
Black holes may not be black or holes, a new theory proposes.
Supermassive black holes in the Milky Way and Andromeda will engulf each other less than 17 million years after the galaxies merge, simulations show.
Using the extinct niobium-92 atom, ETH researchers have been able to date events in the early solar system with greater precision than before. The study concludes that supernova explosions must have taken place in the birth environment of our sun.
On 21 May 2019, from a distance of 7 billion light-years away, our gravitational wave detectors were rocked by the most massive collision yet. From analysis of the signal, astronomers concluded that the detection was the result of two black holes smashing together, weighing in at 66 and 85 times the mass of the Sun respectively.
But what if it was something else? A new study offers a different interpretation of the event. It’s possible, according to an international team of astrophysicists, that the two objects were not black holes at all, but mysterious, theoretical objects called boson stars — potentially made up of elusive candidates for dark matter.
The gravitational wave event, called GW 190521, was a spectacular discovery. The object that resulted from the merger of the two objects would have been a black hole at around 142 times the mass of the Sun — within the intermediate mass range that no black hole had ever been detected before, called the black hole upper mass gap.
Researchers at the Technion-Israel Institute of Technology created a black hole analogue to confirm two of Hawking’s most important predictions, that Hawking radiation arises from nothing (it’s spontaneous) and its intensity does not change over time (it’s stationary).
A new theoretical study has proposed a novel mechanism for the creation of supermassive black holes from dark matter. The international team find that rather than the conventional formation scenarios involving ‘normal’ matter, supermassive black holes could instead form directly from dark matter in high density regions in the centers of galaxies. The result has key implications for cosmology in the early Universe, and is published in Monthly Notices of the Royal Astronomical Society.