Aliens could use supernova to send us messages, claims new SETI study

Interesting Engineering has previously reported how we have been inadvertently signaling our location to aliens for years now and increasingly so due to our use of technology that uses radio waves. However, if we had to send out a message to target a large number of potential planets, the best time would be during a major cosmic activity, something that civilizations would be interested in witnessing.

Supernova SN 2023ixf

One such grand cosmic event is the supernova, the explosion of a star that is not just powerful but also luminous making it quite a spectacle to behold. A supernova typically occurs during the last stages of a massive star and just last month Japanese astronomer Koichi Itagaki spotted one.

Dubbed SN 2023ixf, the supernova is located in the Pinwheel Galaxy and is the nearest star explosion that will be witnessed from the Earth in the past decade. It is hardly a surprise then that astronomers, amateur and professional, have been watching it unravel slowly.

A team of researchers comprising members of SETI as well as prominent universities in the US, however, also look at it as an opportunity for alien civilizations to send us a message.

SETI Ellipsoid

In their paper available on the pre-print server arXiv, the researchers have suggested marking an ellipsoid around the supernova from where both the cosmic activity and planet Earth might be visible. As per researcher estimates, there are 100 stars in this region that have potentially habitable planets orbiting them, and civilizations existing on any of them could be sending us a message.

To ensure that we do not miss it, the team will be using two major telescopes, the Allen Telescope Array in California and the Green Bank Observatory in West Virginia to listen in on the signals emerging from the SETI ellipsoid. Since a supernova can shine for months and years, researchers have a wide window to monitor for signals, if it is ever sent.

The team isn't high on confidence that the exercise will actually lead to a positive outcome but is nevertheless willing to give it a shot since it can serve as a testing ground for similar cosmic events in the future in parts of the galaxies, where life might actually exist. That is if they are willing to beam their presence.

Study abstract:

Several techno-signature techniques focus on historic events such as SN 1987A as the basis to search for coordinated signal broadcasts from extraterrestrial agents. The recently discovered SN 2023ixf in the spiral galaxy M101 is the nearest Type II supernova in over a decade, and will serve as an important benchmark event. Here we review the potential for SN2023ixf to advance ongoing techon-signature searches, particularly signal-synchronization techniques such as the “SETI Ellipsoid”. We find that more than 100 stars within 100pc are already close to intersecting this SETI Ellipsoid, providing numerous targets for real-time monitoring within ∼3◦ of SN2023ixf. We are commencing a radio techno-signature monitoring campaign of these targets with the Allen Telescope Array and the Green Bank Telescope.