These galaxies could rewrite our story of the early universe.
Ancient, massive galaxies haunting the dusty areas of our Universe have hid and are invisible to the eyes of the famous Hubble Space Telescope. But now astronomers scouring infrared data have discovered 39 of them – lurking in strange places in the early universe where (and when) the night sky would look very different from our own.
If you approach any of these long-standing galaxies while you’re in a spaceship, it’s probably obvious to you at least: stars you can see with the naked eye, swirling dust, a big black oneHole in the middle. And if you were there somehow today, it would probably look very different than more than 11 billion years ago, in the early history of our universe.
But the light that came to Earth from these vast, distant galaxies in 2019 had to travel so far that it was billions of years old.It showed us what this part of the universe looked like in the first 2 billion years of its existence. And the light is so altered that the Hubble – built to look in ultraviolet, visible and near infrared – could not see it at all. That’s because these distant galaxies, like most of the distant things in our universe, speed away from us – a result of the dark energy that drives the expansion of space.
As Live Science has already reported, the light from objects moving away from us is stretched to longer, redder wavelengths. And, according to the researchers who discovered them, these super-stellar galaxies rush so fast that the ultraviolet and visible light they emit has completely shifted to the long “submillimeter” wavelength range that even Hubble can not detect. [15unforgettable pictures of stars] As a result, researchers wrote in an article published in the journal Nature on August 7 that most astronomers focusing on the first two billion years of the universe have been working on special balls: galaxies at great distances,to which they nevertheless behave relatively motionless enough that Hubble can see.
But these non-displaced galaxies are probably not the norm. This raises questions about the true abundance of massive galaxies and the density of star formation rates in the early Universe, “the researchers wrote. In other words, how many galaxies really existed at that time and how fast did they make stars? Astronomers have in the past discovered single massive galaxies from the deep past, as the researchers wrote, as well as smaller galaxies that tend to be shrouded in dust.
However, for this work, the team used a series of submillimeter-sensitive telescopes to locate these 39 previously-invisible old galaxies. It was difficult to convince our colleagues that these galaxies were as old as we suspected. Our initial assumptions about their existence were based on infrared data from the Spitzer Space Telescope, “said Tao Wang, lead author of the paper and astronomers at Tokyo University, in a statement.But [the Atacama Large Millimeter / Submillimeter Array in Chile] has sharp eyes and revealed details at sub-millimeter wavelengths that are best suited to look through dust in the early Universe. Still, we needed more data from the imaginative Very Large Telescope in Chile to really prove that we’ve seen ancient massive galaxies where none had been seen before.
These findings are important for early universe models and for explaining the origins of our modern universe. Such a large amount of massive and dusty galaxies in the early universe challenges our understanding of the formation of massive galaxies, “the researchers wrote in the article. [9 The Most Intriguing Earth-Like Planets] Several existing models predict a much lower density of this type of galaxy, although researchers have long suspected that some of them would be out there.
With this new discovery, scientists must go back and refine their models to take into account this new record of previously unseen things. These galaxies, the researchers wrote, are likely to be part of the group that produced modern massive galaxies. But they had much more dust and were much denser than the Milky Way. The night sky would seem much more majestic. The higher density of stars means that there are many more stars near when they look bigger and brighter, “Wang said in the statement.Conversely, the large amount of dust means that distant stars are far less visible, so the background adds to them. These bright nearby stars could be a huge dark void.