Astronomers observed a binary star system that contains a low-mass star and a black hole. The black hole pulls material from its companion star extremely slowly and therefore emits only a very small amount of X-rays. “It is so quiet that it is practically a stealth black hole”.
Astronomers caught a supermassive black hole consuming a star that was drifting in space. The star was eaten so fast by the black hole that the Eddington limit –the theoretical maximum speed limit that defines how fast matter can be consumed by a black hole, was briefly exceeded.
Since the discovery of the Van Allen radiation belts, about 50 years ago, a complete explanation of their dynamics remains elusive. Now, astronomers have developed a new theoretical model than offers a plausible explanation for their formation.
The accretion disk that surrounds black holes emits X-rays that often show rhythmic pulses. These are known as quasi-periodic oscillations (QPOs) and their exact nature remains unknown.
Magnetars are the strongest magnets in the universe. 29 magnetars have been detected to date, but the exact physical mechanism(s) that creates them remains unknown. Recently, astronomers, discovered another unusual feature in one of these magnetars; a wind nebulae.
Astronomers know that supermassive black holes that live in the centre of massive galaxies are fed by hot ionized gas from the galaxy’s halo. Recent observations reveal that chaotic, cold rain is also included in their diet.
An outstanding question in modern astronomy is how can growing black holes be so critical in the formation and evolution of their host galaxy when they are billion times more compact than the galaxies in which they reside in? KMOS, an instrument operating at VLT will allow scientists to answer this question and more.
Astronomers developed a new theory for the formation of supermassive black holes. Data from NASA’s Great Observatories support their theoretical framework.
Astronomers used the W. M. Keck Observatory on Mauna Kea, Hawaii to detect the faintest galaxy of the early universe. The detection was made possible through a phenomenon known as gravitational lensing.
Last June astronomers detected the brightest supernova that has ever been observed, known as ASASSN-15lh. The object had been classified as hydrogen-poor superluminous supernova fuelled by a magnetar, altough it is hotter and more luminous than any other hydrogen–poor supernova thus making the classification uncertain. Now scientists try to uncover the nature of this mysterious source using new observational data.