galaxy mergers tagged posts

Black holes are notorious for gobbling up everything that comes their way, but astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that even supermassive black holes can be picky eaters, and this can have a significant impact on their growth.

This discovery, now published in The Astrophysical Journal, was made by an international team of astronomers led by Makoto A. Johnstone, a Ph.D. candidate with the University of Virginia. The team used ALMA to study seven nearby galaxy mergers hosting supermassive black holes separated by only a few thousand light-years.

How galaxy mergers affect black holes
When two massive, gas-rich galaxies merge, gravity drives vast amounts of cold molecular gas toward the centers of both systems, where supermassive ...

Shining like a brilliant beacon amidst a sea of galaxies, Arp 220 lights up the night sky in this view from NASA’s James Webb Space Telescope. Actually two spiral galaxies in the process of merging, Arp 220 glows brightest in infrared light, making it an ideal target for Webb. It is an ultra-luminous infrared galaxy (ULIRG) with a luminosity of more than a trillion suns. In comparison, our Milky Way galaxy has a much more modest luminosity of about ten billion suns.

Located 250 million light-years away in the constellation of Serpens, the Serpent, Arp 220 is the 220th object in Halton Arp’s Atlas of Peculiar Galaxies. It is the nearest ULIRG and the brightest of the three galactic mergers closest to Earth.

Using the European Southern Observatory’s Very Large Telescope (ESO’s VLT), astronomers have revealed the closest pair of supermassive black holes to Earth ever observed. The two objects also have a much smaller separation than any other previously spotted pair of supermassive black holes and will eventually merge into one giant black hole.

Voggel and her team were able to determine the masses of the two objects by looking at how the gravita...