Radio signal hits Earth after travelling for 8 billion years in space
An international team of scientists have detected an eight-billion-year-old burst of energy. This finding not only shatters the team's previous record by 50%, but also confirms that fast radio bursts (FRBs) can be used to measure the elusive matter between galaxies.
The source of this ancient FRB was identified as a group of two or three merging galaxies, supporting current theories about the origins of these cosmic phenomena.
The team also concluded that with current telescopes, we can detect and pinpoint FRBs dating back to approximately eight billion years.
The FRB, named FRB 20220610A, was detected on June 10, 2022, by CSIRO’s ASKAP radio telescope. This cosmic event released an amount of energy equivalent to our Sun's total emission over 30 years in just milliseconds.
The European Southern Observatory (ESO) Very Large Telescope (VLT) in Chile was then used to locate the source galaxy, which was found to be older and further away than any other FRB source discovered to date.
This discovery reaffirms the concept of using FRBs to 'weigh' the Universe, a theory first proposed by the late Australian astronomer Jean-Pierre ‘J-P’ Macquart in 2020. According to Dr. Ryder, "Our measurements confirm the Macquart relation holds out to beyond half the known Universe."
While the cause of these massive bursts of energy remains unknown, the study confirms that FRBs are common events in the cosmos. They can be used to detect matter between galaxies and better understand the structure of the Universe, says Associate Professor Shannon.
The future of FRB detection looks promising with the construction of the international SKA telescopes in Western Australia and South Africa. These will be even more effective in locating older and more distant FRBs. The nearly 40-metre mirror of ESO’s Extremely Large Telescope, currently under construction in Chile, will then be needed to study their source galaxies.
This discovery is a significant step towards resolving the current conflict in estimating the mass of the Universe.
Associate Professor Shannon explains, "If we count up the amount of normal matter in the Universe – the atoms that we are all made of – we find that more than half of what should be there today is missing." He adds that FRBs can 'see' all the electrons, allowing us to measure how much stuff is between the galaxies.
This could potentially help locate the 'missing' matter believed to be hiding in the space between galaxies.