Astronomers have detected the most distant ‘fast radio burst’ (FRB) ever, providing a potential tool to measure the Universe’s hidden matter. Upcoming telescopes promise to uncover even more distant FRBs.
An international team has spotted a remote blast of cosmic radio waves lasting less than a millisecond. This ‘fast radio burst’ (FRB) is the most distant ever detected. Its source was pinned down by the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in a galaxy so far away that its light took eight billion years to reach us. The FRB is also one of the most energetic ever observed; in a tiny fraction of a second it released the equivalent of our Sun’s total emission over 30 years.
Breaking Previous Records
The discovery of the burst, named FRB 20220610A, was made in June last year by the ASKAP radio telescope in Australia and it smashed the team’s previous distance record by 50 percent.
“Using ASKAP’s array of dishes, we were able to determine precisely where the burst came from,” says Stuart Ryder, an astronomer from Macquarie University in Australia and the co-lead author of the study published today in Science. “Then we used [ESO’s VLT] in Chile to search for the source galaxy, finding it to be older and further away than any other FRB source found to date and likely within a small group of merging galaxies.”
Weighing the Universe With FRBs
The discovery confirms that FRBs can be used to measure the ‘missing’ matter between galaxies, providing a new way to ‘weigh’ the Universe.
Current methods of estimating the mass of the Universe are giving conflicting answers and challenging the standard model of cosmology. “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,” says Ryan Shannon, a professor at the Swinburne University of Technology in Australia, who also co-led the study. “We think that the missing matter is hiding in the space between galaxies, but it may just be so hot and diffuse that it’s impossible to see using normal techniques.”
Understanding the Space Between Galaxies
“Fast radio bursts sense this ionized material. Even in space that is nearly perfectly empty they can ‘see’ all the electrons, and that allows us to measure how much stuff is between the galaxies,” Shannon says.
Finding distant FRBs is key to accurately measuring the Universe’s missing matter, as shown by the late Australian astronomer Jean-Pierre (‘J-P’) Macquart in 2020. “J-P showed that the further away a fast radio burst is, the more diffuse gas it reveals between the galaxies. This is now known as the Macquart relation. Some recent fast radio bursts appeared to break this relationship. Our measurements confirm the Macquart relation holds out to beyond half the known Universe,” says Ryder.
Future Prospects and Tools
“While we still don’t know what causes these massive bursts of energy, the paper confirms that fast radio bursts are common events in the cosmos and that we will be able to use them to detect matter between galaxies, and better understand the structure of the Universe,” says Shannon.
The result represents the limit of what is achievable with telescopes today, although astronomers will soon have the tools to detect even older and more distant bursts, pin down their source galaxies, and measure the Universe’s missing matter. The international Square Kilometre Array Observatory is currently building two radio telescopes in South Africa and Australia that will be capable of finding thousands of FRBs, including very distant ones that cannot be detected with current facilities. ESO’s Extremely Large Telescope, a 39-meter telescope under construction in the Chilean Atacama Desert, will be one of the few telescopes able to study the source galaxies of bursts even further away than FRB 20220610A.
- The ASKAP telescope is owned and operated by CSIRO, Australia’s national science agency, on Wajarri Yamaji Country in Western Australia.
- The team used data obtained with the FOcal Reducer and low dispersion Spectrograph 2 (FORS2), the X-shooter, and the High Acuity Wide-field K-band Imager (HAWK-I) instruments on ESO’s VLT. Data from the Keck Observatory in Hawai’i, US, was also used in the study.
Reference: “A luminous fast radio burst that probes the Universe at redshift 1” by S. D. Ryder, K. W. Bannister, S. Bhandari, A. T. Deller, R. D. Ekers, M. Glowacki, A. C. Gordon, K. Gourdji, C. W. James, C. D. Kilpatrick, W. Lu, L. Marnoch, V. A. Moss, J. X. Prochaska, H. Qiu, E. M. Sadler, S. Simha, M. W. Sammons, D. R. Scott, N. Tejos and R. M. Shannon, 19 October 2023, Science.
The team is composed of S. D. Ryder (School of Mathematical and Physical Sciences, Macquarie University, Australia [SMPS]; Astrophysics and Space Technologies Research Centre, Macquarie University, Sydney, Australia [ASTRC]), K. W. Bannister (Australia Telescope National Facility, Commonwealth Science and Industrial Research Organisation, Space and Astronomy, Australia [CSIRO]), S. Bhandari (The Netherlands Institute for Radio Astronomy, the Netherlands; Joint Institute for Very Long Baseline Interferometry in Europe, the Netherlands), A. T. Deller (Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Australia [CAS]), R. D. Ekers (CSIRO; International Centre for Radio Astronomy Research, Curtin Institute of Radio Astronomy, Curtin University, Australia [ICRAR]), M. Glowacki (ICRAR), A. C. Gordon (Center for Interdisciplinary Exploration and Research in Astrophysics, Northwestern University, USA [CIERA]), K. Gourdji (CAS), C. W. James (ICRAR), C. D. Kilpatrick (CIERA; Department of Physics and Astronomy, Northwestern University, USA), W. Lu (Department of Astronomy, University of California, Berkeley, USA; Theoretical Astrophysics Center, University of California, Berkeley, USA), L. Marnoch (SMPS; ASTRC; CSIRO; Australian Research Council Centre of Excellence for All-Sky Astrophysics in 3 Dimensions, Australia), V. A. Moss (CSIRO), J. X. Prochaska (Department of Astronomy and Astrophysics, University of California, Santa Cruz, USA [Santa Cruz]; Kavli Institute for the Physics and Mathematics of the Universe, Japan), H. Qiu (SKA Observatory, Jodrell Bank, UK), E. M. Sadler (Sydney Institute for Astronomy, School of Physics, University of Sydney, Australia; CSIRO), S. Simha (Santa Cruz), M. W. Sammons (ICRAR), D. R. Scott (ICRAR), N. Tejos (Instituto de Física, Pontificia Universidad Católica De Valparaíso, Chile) and R. M. Shannon (CAS).