Last week I spoke to a trio of astronomers hoping to point some of Earth's most powerful radio telescopes at the distant,that's "blinking" at us in a very unnatural way. The star's strange light curves could hypothetically be explained by the unlikely possibility of alien megastructures passing in front of it. Soon after the news broke, a different group of star watchers -- the SETI Institute -- started pointing its own "ears" toward the star to listen for signs of intelligent life.
Yesterday I spoke with SETI's director of interstellar message composition, Dougas Vakoch, to learn more about that search. "We thought, well, we have the instrument to see if there is an intelligent civilization at this same star that's trying to make contact," he explained. "So by Thursday night [October 15] we had begun our observations with the."
The ATA is made up of over 40 dishes at a site in northern California connected by fiber optic cable and designed specifically to look for radio signals that couldn't be created by nature. Stars and galaxies put out radio waves, but the signals they emit are broad and spread across many frequencies, whereas man-made signals transmit at much narrower bands.
"So far, we've never found anything that is a signal from E.T. ," Vakoch said. "[Radio waves from] stars and galaxies are going to be smeared out across that dial. We're looking for a signal at one spot on that radio dial."
Since last Thursday, the ATA has been working its way through checking all frequencies between 1GHz and 10GHz, one hertz at a time -- that's a total of 9 billion possible channels to check.
Vakoch says any signal the ATA might detect would have to be very powerful, like a beacon of sorts that's been intentionally set up with the purpose of making itself known.
"We're not going to pick up the alien equivalent of 'I Love Lucy'; we're not going to be able to pick up leakage radiation, we're only looking for signals that are directed to us."
To be clear, ATA is not looking for a radio signal coming from hypothetical megastructures that are still on the list of possible explanations for the weird objects theobserved passing in front of KIC 846 2852, originally putting it on astronomers' radar. Rather, the assumption is that if an alien civilization capable of building such structures is in the neighborhood, then perhaps they might also have built a beacon to announce themselves to the universe.
Don't expect to have a definitive answer on the presence of aliens in this star system far, far away too soon, though -- the SETI Institute team plans to go through the scientific process of analyzing data, writing up the findings and submitting them to peer-reviewed journals.
"We've been searching [for alien life] for over 50 years," Vakoch says. "We can easily take our time, whether the results are positive or negative, to bring our conclusions to the scientific community and see what everyone says."
Vakoch said he actually thinks the explanation of KIC 846 2852's blinking that makes the most sense is the one that was proposed in the original research paper written about the star, suggesting a swarm of comets peeled away from the pull of another nearby star, but testing that hypothesis may take months or years. Meanwhile, checking for E.T. can help eliminate aliens as a possibility and lead to a more complete picture of our universe.
"My expectation is we're not going to discover that there are little green men who are sending us a signal from this star, but we're going to understand that nature is once again freakier than we could have ever imagined."