Skip to main content

Ancient cosmic signals: 8-billion-year-old transmission reaches Earth

A recent discovery unveils the most ancient and remote radio burst signals ever detected, originating from a collision of ancient galaxies.

Simulating radio bursts escaping from galaxy clusters and propagating to the Milky Way. Image: ESO

These radio burst signals, known as Fast Radio Bursts (FRBs), emanate from ancient galaxy collisions, providing astronomers with potential clues to unravel the mysteries of missing matter in the cosmos. This discovery marks the most ancient and remote FRB ever observed, confirming that scientists can efficiently employ these signals to “weigh” the universe. FRBs are typically brief, lasting just a few milliseconds. They have remained enigmatic due to their elusive origins. The existence of this record-setting FRB is attributed to a merger of two or three galaxies, offering a potential solution to this cosmic puzzle.



Dubbed FRB 20220610A, it was detected by the Australian Square Kilometre Array Pathfinder (ASKAP), an array of radio telescopes located in Western Australia. In a matter of milliseconds, this FRB appeared to release an amount of energy equivalent to that produced by the Sun over 30 years. The research team published their findings in the journal Science on October 19.

Stuart Ryder, the team leader and researcher at Macquarie University, said, “Using ASKAP’s signal-receiving array, we could precisely pinpoint the source of the burst. Subsequently, we utilized the Very Large Telescope (VLT) at the European Southern Observatory (ESO) in Chile to hunt for the galaxy source, uncovering that it is the most ancient and remote FRB known to date, likely residing within a small group of merging galaxies.”



Through cosmic modeling, starting from the Big Bang and extending to the present day, scientists are aware that roughly half of the matter that should exist in the universe today is missing. This missing matter is not dark matter, the invisible substance that doesn’t interact with light. Researchers believe the missing matter is “ordinary matter,” composed of atoms containing protons and neutrons, also known as baryons. Over many decades, this missing matter has eluded detection by even the world’s largest and most sophisticated telescopes, but recent hypotheses suggest it may be found in the vast voids between some galaxies.

The challenge lies in the sparse distribution of this missing matter, with the equivalent of just two atoms occupying the space of a standard office on Earth. Since the early 2020s, some scientists have contemplated using FRBs as “cosmic scales” to detect this missing matter. As FRBs traverse millions or even billions of light-years, their radiation scatters due to interactions with the missing matter. This scattering allows for the measurement of the FRB’s distance, aiding in determining the universe’s density and, consequently, the localization of the missing matter. Currently, researchers have identified the sources of 50 FRBs, and astronomers anticipate the detection of thousands more similar signals at greater distances.



(Source: Space)