Thanks to data from NASA’s Hubble Space Telescope, a team of astronomers has discovered that a dwarf galaxy is home to a supermassive black hole with a mass equivalent to 21 million suns , making it the smallest known galaxy to host a so massive object. This galaxy, which has a mass of 140 million solar masses, is approximately 54 million light years from Earth .
” It is the smallest and lightest object that we know contains a supermassive black hole,” says Anil Seth, leader of the study that has been published in the journal Nature .
To locate them, the scientists used both the Gemini 8.1-meter optical / infrared telescope located on the Mauna Kea volcano, in Hawaii (USA), as well as the Hubble space telescope. The small galaxy, which has been dubbed M60-UCD1 , suggests that it is likely that there are many ultra-compact galaxies, the result of collisions with other galaxies, that also host supermassive black holes .
The supermassive black hole in this mini galaxy is huge: it is five times bigger than the Milky Way; this is extremely surprising, since our galaxy is 500 times larger and more than a thousand times heavier than the newly discovered galaxy.
“ We think it was once a large galaxy with maybe 10 billion stars in it, but then it passed very close to the center of an even larger galaxy, M60, and in that process all the stars and dark matter on the outside. of the galaxy were ripped apart and became part of M60. That was maybe ten million years ago, ”Seth explains.
