The universe is filled with high-energy radiation, much of which is made of gamma rays belched out by strange pulsing stars and the remnants of supernova explosions. But nearly one-third of all gamma-ray emitting objects seen to date defy identification. The objects were spotted by NASA’s Fermi Gamma-ray Space Telescope, which scans the entire sky over the course of three hours, mapping the powerful spectrum.
An international team of researchers detected a so-called “normal-size” black hole in the distant galaxy Centaurus A, which is located about 12 million light-years away from Earth. By observing the black hole’s X-ray emissions as it gobbles material from its surrounding environment, the scientists determined that it is a low-mass black hole, one likely in the final stages of an outburst and locked in a binary system with another star.
The team of researchers from the University of Leicester (UK) and Monash University in Australia investigated how some black holes grow so fast that they are billions of times heavier than the sun. Professor Andrew King from the Department of Physics and Astronomy, University of Leicester, said that almost every galaxy has an enormously massive black hole in its center. Our own galaxy, the Milky Way, has one about four million times heavier than the sun.
Astronomers have identified the star that may be responsible for a supernova discovered by skywatchers last week. The supernova popped up in the galaxy M95 about 33 million light-years from Earth. It was first reported last week by a several different observers and soon confirmed by major observatories. Now a team led by Nancy Elias-Rosa of Spain’s Institute of Space Studies of Catalonia has compared new photos of the exploded star with pictures taken before the supernova occurred to identify what could very well have been the culprit star.
Studies using X-ray and ultraviolet observations from NASA’s Swift satellite provide new insights into the elusive origins of an important class of exploding star called Type Ia supernovae. These explosions, which can outshine their galaxy for weeks, release large and consistent amounts of energy at visible wavelengths. These qualities make them among the most valuable tools for measuring distance in the universe.
The launch of NASA’s next science mission, a spacecraft to study black holes and other high-energy enigmas of the universe, has been officially delayed. This instrument ,called NuSTAR (Nuclear Spectroscopic Telescope Array), is an X-ray space observatory that will study the universe through the shortest wavelength, highest-frequency range of light. The spacecraft is designed to collect data with greater sensitivity and clarity than any X-ray mission before. As reported Nasa the mission will advance our understanding of how structures in the universe form and evolve.
Astronomers by using NASA’s Hubble Space Telescope were able to find several examples of galaxies containing quasars, which act as gravitational lenses, amplifying and distorting images of galaxies aligned behind them. Quasars are among the brightest objects in the universe, far outshining the total starlight of their host galaxies. Quasars are powered by supermassive black holes. To find these rare cases of galaxy-quasar combinations acting as lenses, a team of astronomers led by Frederic Courbin at the Ecole Polytechnique Federale de Lausanne (EPFL, Switzerland) selected 23,000 quasar spectra in the Sloan Digital Sky Survey (SDSS).
According to new study newfound clouds of gas that stream from gigantic black holes may dictate the pace of star formation in the galaxies around them and the growth of the black holes themselves. These outflows of gas appear to feed on matter that would otherwise fall into an expanding supermassive black hole, halting its growth.As they travel outward, the clouds may also sweep away the raw materials that form new stars in a vast, roughly spherical area known as the galaxy’s bulge, slowing the pace of star formation in the process.
According to new study an intensely bright X-ray beacon shining in the Andromeda galaxy is actually a signpost for a hungry black hole that is gobbling up matter at a furious pace.NASA’s Chandra X-ray observatory first discovered the so-called ultraluminous X-ray source (ULX) in late 2009 in the Andromeda galaxy, which is located about 2.5 million light-years away from our own Milky Way galaxy. Stellar black holes are formed by the collapse of massive stars and typically contain up to 10 or 20 times the mass of the sun. According to the new studies, the black hole causing the ULX object in Andromeda is at least 13 times more massive than our sun and formed after a massive star ended its life in a spectacular supernova explosion.