Searching for extraterrestrial life — by keeping an eye on supernovae

We are not alone in the universe! How close is extraterrestrial life? What is it like?

Finding a needle in a haystack is child's play! 😊

"... For the study, ... chose four historical supernovae — exploding stars — from the past 1,000 years and compared how long it took their light to travel to Earth with light signals from more than 10 million stars recorded by the European Space Agency’s Gaia orbiting observatory. ... found 465 stars whose light took the same amount of time to reach Earth as one of the four supernovae (about 6,300 years, 8,970 years, 16,600 years, and 168,000 years, respectively). He found another 403 stars whose light signals come from an advantageous angle in relation to one of the supernovae. ...

And although none of the 868 star systems yielded evidence of an alien “technosignature” — or signs of extraterrestrial technology, past or present — ... authors said the effort provides a valuable blueprint for conducting additional searches. ..."

From the abstract:

"Spatiotemporal techniques for signal coordination with actively transmitting extraterrestrial civilizations, without the need for prior communication, can constrain technosignature searches to a significantly smaller coordinate space. With the variable star catalog from Gaia Data Release 3, we explore two related signaling strategies: the SETI Ellipsoid, and that proposed by Seto, which are both based on the synchronization of transmissions with a conspicuous astrophysical event. This data set contains more than 10 million variable star candidates with light curves from the first three years of Gaia's operational phase, between 2014 and 2017. Using four different historical supernovae as source events, we find that less than 0.01% of stars in the sample have crossing times, the times at which we would expect to receive synchronized signals on Earth, within the date range of available Gaia observations. For these stars, we present a framework for technosignature analysis that searches for modulations in the variability parameters by splitting the stellar light curve at the crossing time."

Searching for extraterrestrial life — by keeping an eye on exploding stars | YaleNews In a new study, Yale undergrad Andy Nilipour used supernovae to narrow the search for alien civilizations.

Signal Synchronization Strategies and Time Domain SETI with Gaia DR3 (open access)

Geometry in the universe! Pythagoras in space

Figure 3. Diagram of the SETI Ellipsoid, which has its foci at the source event (purple dot) and Earth (green dot).