The Universe contains 10 times more galaxies than scientists thought

More than a trillion galaxies lurk in the depths of space, and a new census reveals there are 10 times more galaxies in the observable Universe than previously thought.

An international team of astronomers used deep-space images and other data from the Hubble Space Telescope to create a 3D map of the Universe, which contains between 100 and 200 billion galaxies. In particular, scientists relied on new technologies from the Hubble Deep Field, which revealed the most distant galaxies using the telescope.

The researchers then incorporated new mathematical models to calculate other galaxies that have not yet been imaged by telescopes but may exist. To add to the top of the universe, at least 10 times more galaxies than are currently known are needed. But these unknown galaxies must be either too faint or too distant to be seen with today’s telescopes.

«It’s mind-boggling that more than 90 percent of the galaxies in the universe have yet to be observed,» Christopher Conselice, a professor of astrophysics at the University of Nottingham in the UK who led the study, said in a statement. «Who knows what other interesting features we’ll find when we observe these galaxies with next-generation telescopes.»

Looking into deep space also means looking into the past, because the speed of light is limited, and it takes a long time for light to reach the next new galaxy as it travels through space. During the study, Conselice and his team «visited» almost the deepest parts of the universe—a full 13 billion light-years away. This allowed the researchers to see partial snapshots of the universe’s evolution, beginning 13 billion years ago, or less than 100 million years after the Big Bang.

They discovered that the early universe contained even more galaxies than today. Those distant galaxies were small and dwarf-sized. As the universe evolved, “young” galaxies merged together to form larger ones.

In a separate statement, Conselice said the results are “very surprising because we know that during the 13.7 billion years of cosmic evolution since the Big Bang, galaxies grew by forming stars and merging with other galaxies. Finding a larger number of galaxies in the past suggests that a significant part of evolution occurred through extensive mergers, thereby reducing the number of galaxies.”

The results of the study are published in the journal “

The Astrophysical Journal”.
Original article at Live Science.