The majority of the universe is in total darkness, meaning we cannot see it, but can only detect the gravitational effects coming from cosmic bodies hidden in the deepest parts of space. Even then, scientists can only capture a handful of signals from there. Black holes, supernovas, planets, and stars bigger than the sun – there are still billions of celestial bodies to be discovered, and many of them we won’t be able to catch a glimpse of. On the other hand, astronomers have found strange structures that might hint at one big question of the universe.
Einstein’s general relativity theory serves as the basis for every major study
Every major study about how the universe operates has to rely on Einstein’s general relativity theory. From the time he published his study in the early 1920s, to the creation of the dark energy concept by Edwin Hubble late in the decade, to Frank Zwicky with the dark matter theory, almost every major discovery is based on the general relativity theory.
Dark energy is the invisible force responsible for the expansion of the universe happening right now. Dark matter, on the other hand, is the force responsible for holding galaxies together. Recently, another major theory emerged, substituting the dark matter concept for the simplicity of gravity – anything with mass can bend spacetime, and for this reason, there are gravitational fields powerful enough to keep everything steady, like the sun in the solar system. But now, astronomers have figured out the solution to a 100-year-old universe mystery.
Astronomers find a strange structure in the universe hiding missing matter
For the first time, a group of astronomers managed to track down the universe’s so-called “missing matter” — the regular stuff like protons and neutrons that make up everything we see, but that has been suspiciously absent when scientists ran the numbers.
To find it, they used fast radio bursts (FRBs) – sudden, powerful flashes of radio waves coming from galaxies billions of light-years away. These bursts travel through space and pick up tiny changes depending on how much matter they pass through. Think of it like shining a flashlight through fog – the denser the fog, the more the light spreads out.
The team focused on 69 of these FRBs, all with known distances from Earth. One of them, named FRB 20230521B, came from 9.1 billion light-years away — the farthest FRB ever recorded. Most of these were spotted using a network of 110 radio antennas in California, while other telescopes in Hawaii, San Diego, and Australia helped determine where the signals came from and how far they traveled.
How do they measure the amount of matter?
By analyzing how the FRB signals spread out, the researchers were able to measure the amount of ordinary matter between us and those distant galaxies. It turns out that about 76% of it is floating in the vast space between galaxies – a region called the intergalactic medium. Another chunk, around 15%, is stuck in galaxy halos, while the rest is inside galaxies, in stars, or cold gas. This breakdown has been confirmed with actual observations, instead of just simulations, for the first time.
Implications for future studies and research
The findings help researchers get a clearer picture of how galaxies grow and change. They also show that FRBs can be useful tools for solving other problems in cosmology, like estimating the mass of neutrinos — subatomic particles that barely interact with normal matter. While the standard model of physics says neutrinos should have no mass, observations show they do, even if it’s a minuscule amount. Figuring out their exact mass could point to new physics beyond what current theories explain.