The mystery of a rare change in the behaviour of a supermassive black hole at the centre of a distant galaxy has been solved by an international team of astronomers using ESO’s Very Large Telescope along with the NASA/ESA Hubble Space Telescope and NASA’s Chandra X-ray Observatory. It seems that the black hole has fallen on hard times and is no longer being fed enough fuel to make its surroundings shine.
Astronomers have made the first accurate measurement of the abundance of oxygen in a distant galaxy. Oxygen is created inside stars and released into interstellar gas when stars die. Quantifying the amount of oxygen, the third-most abundant chemical element in the universe, is key to understanding how matter cycles in and out of galaxies.
A gravitational lens system has been discovered by undergraduate students examining images from the 8.2-metre Subaru Telescope’s Hyper Suprime-Cam. Dubbed the “Eye of Horus” due to the system’s uncanny resemblance to the sacred eye of the ancient Egyptian goddess, it is formed by a galaxy 7 billion light-years from the Earth bending the light from two more galaxies directly behind it.
In 2015, Dr. David Sobral of Lancaster University led a team that found the first example of a spectacularly bright galaxy in the young universe named CR7 which may harbour first generation stars. Now, astronomers have identified a family of incredible galaxies that could shed further light on the transformation of the early universe known as the “epoch of reionisation.”
This multicoloured swirl of yellow and blue shows a prominent ring of gas near the North Celestial Pole. The pole appears to be fixed in place, while the rest of the night sky slowly circles around it because of Earth’s rotation. This image comes courtesy of ESA’s Planck satellite, which spent years mapping the entire sky in exquisite detail between 2009 and 2013.
The Instituto de Astrofísica de Canarias (IAC) set out to test the limit of observation which can be reached using the largest optical-infrared telescope in the world: the Gran Telescopio CANARIAS (GTC). The observers managed to obtain an image 10 times deeper than any other obtained from the ground, observing a faint halo of stars around the galaxy UGC0180.
Astronomers recently found that a galaxy about 30 million light-years away nicknamed Leoncino, or “little lion,” contains the lowest level of heavy chemical elements, or “metals,” ever observed in a gravitationally bound system of stars. The elemental make-up of metal-poor galaxies is very close to that of the early universe.
Peering deep into the heart of our home galaxy, the Milky Way, the Hubble Space Telescope reveals a rich tapestry of more than half a million stars. Most of the stars pictured in the image are members of the Milky Way nuclear star cluster, the densest and most massive star cluster in the galaxy. Hidden in the centre is the Milky Way’s resident supermassive black hole.
Astronomers at the University of Massachusetts, Amherst report that they have observed the most luminous galaxies ever seen in the universe, objects so bright that established descriptors such as “ultra-” and “hyper-luminous” used to describe previously brightest known galaxies don’t even come close.
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