The Webb Telescope looks back to the beginning of time. He saw early galaxies there that were nothing like today’s. They are not elliptical, nor irregular, nor spiral. They are like baguettes or beer sticks. Or perhaps caterpillars that chew their way through reality a few hundred million years old. This is probably how the germ of the Milky Way looked.
Cosmic caterpillars from the dawn of time. Credit: Pandya et al. (2024), arXiv.
As I’m sure everyone knows by now, the James Webb Space Telescope sees further than any comparable telescope has ever seen. It looks into the very early universe. And as it turns out, he sees remarkable things there.
Viraj Pandya. Credit: Columbia University.
Viraj Pandya of Columbia University and his colleagues used the Webb Telescope to survey very early galaxies. They analyzed images taken by Webb as part of the Cosmic Evolution Early Release Science (CEERS) Survey, covering the early universe up to just 600 million years after the Big Bang.
Pandya seems to have a penchant for Italian pastries. It turns out that galaxies in the early universe are typically flattened, with most of them reminding Pandya of Italian baguettes, or “bread” sticks known as grissini. In our country, they are more common as “beer” or “bakery” sticks in various variants.
Galaxies in the early universe. Credit: NASA, ESA, CSA, STScI, Steve Finkelstein (UT Austin), Micaela Bagley (UT Austin), Rebecca Larson (UT Austin).
Less common in the early universe are galaxies that look like a pizza crust. Spherical galaxies are rare there, which Pandya likens to balls of pizza dough. In the end, Pandya gets somewhat lost in the comparisons, because their publication talks about bananas, which the authors rather unhappily derive from some kind of graph that is not very comprehensible to the layman. According to the author of this text, early galaxies are bright cosmic caterpillars that bite through the reality of the early universe.
If we were to go back in time, what would the Milky Way look like in this Italian bakery, or perhaps an insectarium? According to the authors of the study, the young (proto)Milky Way was most likely a “caterpillar.” At the same time, it is clear that it was much smaller than today. Galaxies at the time had understandably little time to grow. The galaxies we observe today in the nearby universe have undergone billions of years of development, full of dramatic galactic cannibalism – and have sprung up accordingly.
But why the caterpillar/rod shape? It is a mystery to scientists. According to one hypothesis, the early universe was full of filaments of dark matter, which formed a cosmic “skeleton,” on which cosmic material and stars were then “hung.” Such filaments, if they existed, should still be in space today. However, with the expansion of the universe, they would increase in size and become rarer, due to which they would no longer shape the galaxies into the form of caterpillars. Which obviously they don’t shape. The fascinating research into early galaxies will undoubtedly continue.
Video: Galaxies Are Going Bananas. And Breadsticks, Too
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2024-01-21 17:42:19
#ellipses #spirals #Early #galaxies #resembled #caterpillars
