Such images reveal valuable information about how galaxies form and evolve, and help track the location of elusive dark matter, which makes up about 80% of the mass of the Universe.

In 2014, astronomers captured the first image of the cosmic web based on the radiation from a quasar, an object billions of times more massive than our Sun and considered one of the brightest objects in the Universe. In 2019, another study used data from young, forming stars to provide a proxy for the cosmic web. Now, astronomers have directly captured its light at a distance of 10 to 12 billion light years away.

According to cosmological models, more than 60% of the hydrogen created after the Big Bang approximately 13.8 billion years ago collapsed and formed spatial structures, which in turn collapsed and formed the cosmic web of filaments that we see today – threads of cosmic matter consisting from dust and gas. These filaments connect galaxies and enable their growth and star formation. Although this is just speculation, previous research has also suggested that galaxies form where these filaments intersect.

To take the latest image of intersecting filaments, the team used data from the telescope. Keck, installed at the observatory on the Mauna Kea volcano in Hawaii. The device is configured to detect radiation from hydrogen, which is the main component of the cosmic web. The resulting 2D images were then combined into a 3D map based on the detected radiation emanating from the cosmic web.

To notice these faint emissions, the team first had to deal with the problem of light pollution. The dim light of the cosmic web can easily be confused with the light of the Hawaiian sky, atmospheric aurora, and even the light of our Milky Way.

So the team decided to take photographs of two different parts of the sky at different distances. The scientists then took the background light from one image and subtracted it from the other, and vice versa. As a result, only the web’s filament network remained, as simulations predicted in 2019.

Images like those produced in the new study can help scientists better understand how galaxies form and evolve over eons.

One way to determine the mass of a galaxy is to study its rotation curve, measuring the speed of the stars in the galaxy depending on their distance from the galactic center. The speed at which a star rotates is proportional to the amount of mass in its orbit, so using the rotation curve of a galaxy, you can plot the distribution of the mass function over the radius and get an idea of ​​​​the total mass of the galaxy. Scientists have measured rotation curves for several nearby galaxies, such as Andromeda, so they know the masses of many galaxies very accurately.

But because we’re inside the Milky Way itself, we don’t have a good view of the stars throughout the galaxy. There is so much gas and dust towards the center of the galaxy that we can’t even see the stars on the far side. So instead, scientists measure the rotation curve using neutral hydrogen, which emits faint light at a wavelength of about 21 centimeters. This is not as precise as measuring stars, but it still gave a general idea of ​​the mass of our galaxy.

Astronomers also studied the movements of globular clusters rotating in the halo of the Milky Way. From these observations, the best estimate of the Milky Way’s mass is about one trillion solar masses, with small uncertainties.

This new study is based on the third dataset from the Gaia spacecraft. It contains information on the positions of more than 1.8 billion stars and the movements of more than 1.5 billion stars. Although this is only a fraction of the estimated number of stars in our galaxy, which is between 100 and 400 billion, it is a large enough number to calculate an accurate rotation curve.

That’s exactly what the team of scientists did. The resulting rotation curve is so accurate that the team was able to determine Kepler’s law for the outer region of the Milky Way, where the velocities of stars begin to decline, consistent with Kepler’s law, since virtually all of the galaxy’s mass is closer to the galactic center.

Kepler’s Law allows the team to place a clear upper limit on the mass of the Milky Way. And what they found was quite surprising. The best fit to the data estimated the mass at about 200 billion solar masses, a fifth of previous estimates. The absolute upper limit for the Milky Way’s mass was 540 billion solar masses, which means the Milky Way is at least half as large as previously thought. And given the known normal matter in the galaxy, this means that the Milky Way contains significantly less dark matter.

An Einstein ring is a rare type of gravitationally lensed object that was predicted by Albert Einstein’s theory of relativity. Gravitational lensing occurs when the gravity of a massive object, such as a cluster of galaxies or a black hole, bends the space-time around it and light emitted by more distant objects, such as galaxies or supernovae, passing through this curved space-time appears bent and distorted to an observer .

This effect “magnifies” the object being lensed, similar to how a magnifying glass works, allowing astronomers to study distant objects in more detail than is usually possible. Most gravitationally lensed objects form arcs around the object. But the “true Einstein Ring” forms a complete circle around the object.

In a new study, the astronomer discovered a complete Einstein ring, called JWST-ER1, discovered as part of the COSMOS-Web project – creating a detailed map of more than 500,000 galaxies during 200 hours of continuous JWST observations.

JWST-ER1 consists of two parts: JWST-ER1g, a compact galaxy that is the foreground lensing object, and JWST-ER1r, the light from a more distant galaxy that forms a luminous ring. JWST-ER1g is about 17 billion light-years from Earth, and JWST-ER1r is another 4 billion light-years further away.

Thanks to JWST-ER1’s full ring, the researchers calculated the mass of the lens galaxy, determining how much it distorted the space-time around it. This galaxy has a mass equivalent to about 650 billion Suns, making it unusually dense for its size. Some of this mass could be explained by dark matter, but even so, it is unlikely that there will be enough stellar mass to explain the rest of the galaxy’s mass.

Galaxies of the same age and density have been discovered before, suggesting that these ancient star factories have something in common that makes them so massive. One explanation is that these galaxies contain much more dark matter than expected, while another theory suggests that they may contain more low-mass stars than young galaxies. But to find out the true cause, scientists need additional observations and work on them.

This is not the first true Einstein Ring discovered by JWST. Until now, the farthest object discovered was a ring at a distance of about 14.7 billion light years. The age of the Universe itself is estimated to be about 13.7 billion years, but due to its constant expansion, the light of the most ancient objects must travel a much greater distance to reach our telescopes.