While the Universe is a big place, and everything in it may look just like all higgledy-piggledy places, there is more structure than we can see.
According to our models of the Universe, and ascending evidence, filaments of dark matter connect large objects such as galaxies and galaxy assemblages in a vast cosmic web.
It is on these filaments that hydrogen flows, feeding into the galaxies, but they are not so easily seen – among the bright stars and galaxies and galactic nuclei, the diffuse diffusion from diffuse hydrogen in a place difficult to see, forever a map of mind.
We got a step closer, though. At the end of years of work, an international team of astronauts led by Roland Bacon of the Lyon Astrophysical Research Center in France has just designed several filaments of the cosmic web early in the Universe, about 12 billion years old. light away.
Hydrogen filaments (in blue). (Roland Bacon / David Mary / ESO / NASA)
Their results are just some of the strongest evidence yet for the cosmic web; they also found evidence that a large population of corrosive galaxies powers hydrogen glow within the filaments. This discovery could dramatically change our understanding of galaxy formation in Earth’s childhood.
Because the cosmic web is so difficult to see, much of our evidence so far has been inconclusive. Some scientists have looked at the way a mass bends space-time – a gravitational lens – for battles in the path of distant light, which shows that strands of the cosmic net are between the his store and us.
Other researchers use light quasars, distant bright galaxies, to search for light with hydrogen throughout the filaments.
(Jeremy Blaizot / projet SPHINX)
Above: A cosmological simulation of the distant Universe, with light emitted by hydrogen atoms in the cosmic net in an area of about 15 million light-years across.
Bacon and his team took a different approach – looking at a tiny teenage piece of space for a very long time, with an awesome telescope. Using the MUSE instrument on a Very Large ESO Telescope in Chile, the team delivered an amazing 140-hour view of a segment of space that also appeared in the Hubble Space Telescope Ultra-Deep Range.
A similar search was made, with astronauts looking for layers of light in a browser of galaxies – gas fibers ionized by the galaxies themselves. Here, too, the work of the Bacon team differs from previous efforts: the earlier research examined an extreme environment, while the new research deliberately looked somewhere anonymous.
After the design phase, the team’s ideas took months to get, from August 2018 to January 2019. They had to be taken in blocks through the new Moon to deter humans.
(Thibault Garel / Roland Bacon)
Above: A cosmological simulation of a filament made up of hundreds of thousands of tiny galaxies (as seen in the space on the left, as seen by MUSE on the right).
The team then had to process and analyze the data, which took another year. But it was worth it – not only were 40 percent of the galaxies in their data unknown in the Ultra Deep Field, but the researchers had revealed an image of clear hydrogen in filaments of the net. cosmic, spanning millions of light years.
Surprisingly, the team’s study shows that the majority of hydrogen emissions could be accounted for by a large population of star-forming shadowy galaxies, spread out throughout the filament. . We do not see them alone, of course – they are far too long to solve – but future work could help to confirm this discovery, with a profound impact on our understanding of the Universe.
If dwarf galaxies are also guided across cosmic web filaments, such as water drops down a piece of string, it may help to explain how galaxies formed and grew – and grew to precious early sizes. in the Universe, a question that cosmologists are concerned about.
In addition, detecting the scattering of star-forming dwarf galaxies could help us find more filaments of the cosmic web, and a deeper understanding of how everything is in the connected Universe.
The research was published in Astronomy & Astronomy.