Space

Glow of "cosmic web" filaments directly imaged for the first time

Glow of "cosmic web" filaments...
A simulated image of the cosmic web, where each point of light represents a galaxy undergoing star formation
A simulated image of the cosmic web, where each point of light represents a galaxy undergoing star formation
View 4 Images
A simulated image of the cosmic web, where each point of light represents a galaxy undergoing star formation
1/4
A simulated image of the cosmic web, where each point of light represents a galaxy undergoing star formation
A chart illustrating the section of the universe in space and time that the team imaged in the new MUSE study – the blue squares represent the regions where the filaments were most clearly visible
2/4
A chart illustrating the section of the universe in space and time that the team imaged in the new MUSE study – the blue squares represent the regions where the filaments were most clearly visible
A hydrogen filament that stretches some 15 million light-years long, discovered by MUSE in the constellation Fornax – the background image is from Hubble
3/4
A hydrogen filament that stretches some 15 million light-years long, discovered by MUSE in the constellation Fornax – the background image is from Hubble
An illustration of the structure MUSE sees (right) compared to a simulated image (left) of the unseen galaxies that produce the diffuse light
4/4
An illustration of the structure MUSE sees (right) compared to a simulated image (left) of the unseen galaxies that produce the diffuse light
View gallery - 4 images

On a scale that’s hard to fathom, the universe is made up of a “cosmic web” of hydrogen filaments that feed and form galaxies. Now, astronomers have made the first direct observations of light from this web, by staring at a patch of sky with a powerful deep-field telescope to detect faint dwarf galaxies.

Physics and simulations have long predicted that the large-scale structure of the universe looks like it was spun by some colossal spider. Dark matter seems to have been distributed into filaments spanning lightyears, and that attracted regular matter like dust and gas to gather along those threads, too. Galaxies and clusters tend to clump in the nodes where these filaments meet.

Hints of these cosmic webs have been indirectly observed before, through gravitational lensing or thanks to the bright light from quasars illuminating the gas. But now, astronomers have managed to detect light from the hydrogen gas itself.

To do so, the team used the Multi Unit Spectroscopic Explorer (MUSE) instrument onboard the Very Large Telescope (VLT) in Chile. They pointed this instrument at one patch of sky and stared for 140 hours. This long exposure time allowed the diffuse light of the hydrogen emissions to come into focus, revealing 22 filament structures in the very early universe – between 0.8 and 2.2 billion years after the Big Bang.

A hydrogen filament that stretches some 15 million light-years long, discovered by MUSE in the constellation Fornax – the background image is from Hubble
A hydrogen filament that stretches some 15 million light-years long, discovered by MUSE in the constellation Fornax – the background image is from Hubble

It was previously thought that any glow from these filaments would have been caused by radiation from the cosmic microwave background heating up the gas in the filaments. But when the team ran follow-up simulations, they found that the light was likely coming directly from billions of dwarf galaxies.

Interestingly, while this region had already been studied as part of Hubble’s Ultra-Deep Field survey, the new observations were able to see 40 percent more galaxies that Hubble hadn’t been able to see. And even then, many more galaxies were too faint for MUSE to pick out individually.

The team says that these extra galaxies may require an update to our understanding of how galaxies form.

The research was published in the journal Astronomy & Astrophysics.

Source: CNRS

View gallery - 4 images
9 comments
9 comments
Chris Coles
It is inevitable that gravitational fields will be significantly denser along a line between large objects such as galaxies; always remembering that the filaments will be formed from electromagnetic force field attachments between gas molecules.
Pierre Collet
The actual imaage (placated over a Hubble image) is much less impressive than the simulated one, but at least, we now see that these filaments exist, and that what looked like independent stars and galaxies are in fact interconnected by these gossamer strands of hydrogen...
bwana4swahili
Our Universe never ceases to amaze!
Graeme S
We are all connected, everything is connected, now who made all that happen?
Michael Lombardi-Nash
Asking who created this is the anthropomorphic point of view; in actuality it was the technology and the scientists who created it
Worzel
Try googling ''Electric Universe'' and the ''Thunderbolts Project'' and be enlightened.
Everything in the Universe is electric!
Mark Rays
Yes for decades the Plasma Universe theory has predicted it and explained it
KrakaTaoJones
@Worzel And here I thought I was the only one who followed Wal Thornhill and Electric Universe theory.
Chris
Electrically ionized plasma forms these multilayered filaments. Known as Birkeland currents they form amazing counter-rotating conductors which probably generate current by electro- inductive action. This is suggested by Prof Don Scott.