First Coordinated Green Bank Telescope/Allen Telescope Array Observes Possible Source of the WOW! Signal
In May 2022, the International Journal of Astrobiology published a paper suggesting a candidate source of the WOW! Signal: a possible Sun-like star in the Gaia Archive, 2MASS 19281982-2640123, located 1,788 light-years from Earth.
The paper’s author, Alberto Caballero, suggested 2MASS 19281982-2640123 would be an ideal target for observations searching for a possible technosignature.
“The paper led to Breakthrough Listen‘s first collaboration between the Green Bank Telescope (site of the first-ever SETI observation by Frank Drake in 1961) and the SETI Institute’s Allen Telescope Array (the first radio observatory built especially for SETI observations),” said Karen Perez, graduate student at Columbia University, visiting graduate student at Breakthrough Listen and lead author on the AAS Research Note.
“This is the first time a targeted search for the WOW! Signal has been conducted, and having access to both telescopes to conduct such a search is of great importance for future interesting candidates, whether that be in relation to the WOW! Signal, or candidates from other ongoing surveys.”
“A swift response to a target of opportunity is one of the main specifications of the Allen Telescope Array (ATA), and it is remarkable to see the ATA teaming up with one of the most sensitive telescopes on the planet,” said Wael Farah, SETI Institute Research Scientist and co-author of the AAS Research Note. “This is an excellent model of how follow up of astronomical transient events, including potential SETI candidates, can be conducted.”
The WOW! Signal was first observed on August 15, 1977, by the Ohio State University’s Big Ear radio telescope near the 21-cm hydrogen line at 1420 MHz and has not been redetected.
The teams conducted their observations at the same time, on May 21, 2022. Greenbank conducted two 30-minute observations, and the ATA conducted six 5-minute observations, using its newly developed beam-former backend for signal processing. Both telescopes observed a total of 9 minutes and 40 seconds simultaneously.
While the observations did not detect a technosignature candidate, there are many more possible stars from which the WOW! Signal could have originated, presenting many more opportunities for Breakthrough Listen and the SETI Institute to collaborate on their shared quest to find technologically advanced civilizations beyond Earth.
The data is open source and can be found here: https://seti.berkeley.edu/wow/
This work is published as an AAS Research note here. Karen Perez, Columbia University, presented at the 51st IAA Symposium on the Search for Extraterrestrial Intelligence at the International Astronautical Congress in Paris, France.
