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Lost in space: Nasa reveals ‘loneliest galaxy’ floating in a 150 million light year-wide abyss Astronomers have captured a spectacular image of a 'lonely' galaxy stranded on the edge of an abyss. The galaxy is located next to a 150 million light year-wide patch of interstellar emptiness called the Local Void. Perched on its cusp, NGC 6503 also known as the 'Lost in Space Galaxy' is thought to be around 18 million light years away from Earth. 'Although the universe may seem spacious most galaxies are clumped together in groups or clusters and a neighbour is never far away,' Nasa wrote. 'But this galaxy, known as NGC 6503, has found itself in a lonely position.' NGC 6503 spans some 30,000 light-years, about a third of the size of the Milky Way. This Hubble Space Telescope image shows NGC 6503 in striking detail and with a rich set of colours. Bright red patches of gas can be seen scattered through its swirling spiral arms, mixed with bright blue regions that contain newly forming stars. |
Black hole is a region of spacetime exhibiting such strong gravitational effects that nothing not even particles and electromagnetic radiation such as light can escape from inside it. The theory of general relativitypredicts that a sufficiently compact mass can deform spacetime to form a black hole.
The boundary of the region from which no escape is possible is called the event horizon. Although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed.In many ways a black hole acts like an ideal black body, as it reflects no light.
Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe.
Black holes of stellar mass are expected to form when very massive stars collapse at the end of their life cycle. After a black hole has formed, it can continue to grow by absorbing mass from its surroundings. By absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses may form. There is general consensus that supermassive black holes exist in the centers of most galaxies.
