Scientists spot 39 ancient galaxies that were 'invisible' to Hubble

These Gargantuan Galaxies, Hidden in Plain Sight, Could Rewrite Universe's Early Days

These Gargantuan Galaxies, Hidden in Plain Sight, Could Rewrite Universe's Early Days

In an effort to find more typical galaxies, an global group of astronomers led by Tao Wang from the University of Tokyo used the Atacama Large Millimeter/submillimeter Array (ALMA) radio observatory in Chile, as well as other telescopes.

Scientists knew that there should be some objects like these out there, and the researchers said that as these galaxies age, they should turn into massive elliptical galaxies like those we see closer to the Milky Way.

Wang and colleagues hope these galaxies can explain both how today's galaxies began, but also how so many of them came to exist so early in the universe, contrary to most current theories. The amount of stretching allows astronomers to calculate how far away something is, which also tells you how long ago the light you're seeing was emitted from the thing in question. So the astronomers turned to the Atacama Large Millimeter/submillimeter Array (ALMA), a spread of radio dishes in Chile.

Another reason these galaxies appear so weak is because larger galaxies, even in the present day, tend to be shrouded in dust, which obscures them more than their smaller galactic siblings.

The bigger a galaxy, the bigger the supermassive blackhole at its heart, say the scientists.

"It was tough to convince our peers these galaxies were as old as we suspected them to be", said Wang, the paper's lead author, in a press release. "Our initial suspicions about their existence came from the Spitzer Space Telescope's infrared data".

But Elmegreen compared that growth to a drip, and the discovery of these ancient massive galaxies is like leaving a faucet dripping and returning just a bit later to see the bathtub had filled up. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences.

The new prevalence of these galaxies, which are connected with supermassive black holes and dark matter, contradicts the current known models of the universe. At this point, most of the information about the mechanisms of star formation has been collected from populations of galaxies observed in rest-frame ultraviolet light. But ALMA has sharp eyes and revealed details at submillimeter wavelengths, the best wavelength to peer through dust present in the early universe.

"Residing in the most massive dark matter haloes at their redshifts, they are probably the progenitors of the largest present-day galaxies in massive groups and clusters", the team write. But if we lived in one of these massive ancient galaxies, the view would be different.

"For one thing, the night sky would appear far more majestic".

"The greater density of stars means there would be many more stars close by appearing larger and brighter". "ALMA is not good at this and we need something more".

He added that he was eager for upcoming observatories like the space-based James Webb Space Telescope to show us "what these primordial beasts are really made of".

The invention of such massive, star-forming galaxies when the universe was lower than 2 billion years outdated matches nicely with previous observations of huge, quiescent galaxies later in cosmic historical past.