'No signals' detected from targeted ET hunt with VLBI
By Shin Na-yun
The hunt for other intelligent civilizations has a new technique in its arsenal, but its first use has turned up no signs of alien broadcasts, according to BBC.
Australian astronomers used "Very Long Baseline Interferometry(VLBI)" to examine Gliese 581, a star known to host planets in its "habitable zone," but they couldn't found the signal. They posted this report in the Astronomical Journal online.
VLBI is the process of using several or many telescopes that are distant from one another, carefully combining their signals to make them effectively act as one large telescope, peering intently at a tiny portion of the sky. This system is one of radio astronomy's highest-resolution techniques to work.
Gliese 581, a red dwarf star about 20 light-years away, is a particularly interesting candidate for the search for Extraterrestrial Intelligence, or SETI (Search for Extraterrestrial Intelligence). It has six planets, two of which are "super-Earths" likely to be in this habitable zone.
Although the team trained the Austrian Long Baseline Array onto Gliese 581 for eight hours, listening in on a range of radio frequencies, there was no signal from ET. “Figuring out 'is this ET or AT&T?' isn't always easy, and VLBI gives you a good way of discriminating, because if you find something from that tiny, tiny dot on the sky you can say that's not one of our satellites," Dr. Shostak said.
He added that the team's negative result was not disheartening, because the odds have it that the hunt for aliens, if it is ever to find them, will require thousands or millions of observations of this kind.
Also, " The fact that we look at one star system and don't find a signal doesn't tell you that there's no intelligent life," he said.