Astronomers have discovered the first evidence of giant black holes in colliding dwarf galaxies, and it offers important information about the formation of galaxies and the growth of black holes in the early universe. Results are from data from NASA’s Chandra X-ray Observatory, WISE and CFHT.

Astronomers have discovered the first evidence of giant black holes in dwarf galaxies on a collision course. This result from NASA’s Chandra X-ray Observatory has important implications for understanding how the first black hole and galaxy wave grew in the early universe.

Collisions between pairs of dwarf galaxies found in the new study caused the black holes to grow, pulling gas towards the giant black holes contained within each. Eventually, a possible black hole collision will cause them to evolve into much larger black holes. Galaxy pairs will also merge into a single galaxy.

Scientists believe that several hundred million years after the Big Bang, the universe was filled with small galaxies known as “dwarf galaxies.” Many merged with others in the crowded, smaller volume of the early universe, beginning the construction of the larger and larger galaxies currently observed around the immediate universe.

Dwarf galaxies, by definition, contain stars with a total mass of about 3 billion times the mass of the Sun, compared to the total mass of about 60 billion Suns for the Milky Way.

The earliest dwarf galaxies are impossible to observe with modern technology, as they are extremely dim at great distances. Astronomers were able to observe both in the process of merging at much closer distances to Earth, but neither galaxies had any signs of black holes.

“Astronomers have found many examples of black holes on their collision course in large galaxies that are relatively close,” said Marko Michik of the University of Alabama in Tuscaloosa, who led the study. “But looking for them in dwarf galaxies is much more difficult and has been unsuccessful so far.”