In an effort to detect the radio emissions from a hypothetical extraterrestrial intelligence, it helps to know where to look. Space, after all, is a very big place and the chances of accidentally stumbling across an alien television signal is very low.

So, using data from the Kepler space telescope , astronomers are becoming more focused on "listening" for radio signals coming from stars known (or at least thought) to have planets orbiting them. And it seems the first "candidate" signals have been detected!

ANALYSIS: SETI to Hunt for Aliens on Kepler's Worlds

But before you start popping the "we've discovered ET!" champagne corks, this first signal is most likely terrestrial in origin.

"We've started searching our Kepler SETI observations and our analyses have generated some of our first candidate signals," scientists of the University of California, Berkeley announced on Friday.

Sadly, the first candidate signals aren't lucky detections of alien radio transmissions, they're "undoubtedly examples of terrestrial radio frequency interference (RFI)."

Although it's interference from a source here on Earth, the detection of any artificial signal provides the UC Berkeley team with a great opportunity to understand the kind of artificial (alien) signals they hope to eventually discover.

more here

First Look at Kepler SETI Data
Update: Friday, January 6, 2012 After posting the plots below on January 5, it became clear that we had not stated as definitively and absolutely as possible that these signals are interference. We have update the post to make this clear. Sorry for any confusion.
We've started searching our Kepler SETI observations and our analyses have generated a few 'hits,' but all are undoubtedly examples of terrestrial radio frequency interference (RFI). Each of the signals below is shown in a pair of plots, one from an observation of Kepler Object of Interest (KOI) 817 and one from an observation of KOI-812. During an observation, we alternated between targets to enable us to rule out signals seen coming from two different places in the sky. If we see a signal coming from multiple positions on the sky, like the ones below, it is very likely to be interference.

What do these plots represent?

These are plots of electromagnetic energy as a function of frequency and time. Brighter colors represent more radio energy at a particular time and frequency. For example, a radio station transmitting at 101.5 MHz would produce a large amount of energy near that frequency.

Why are these signals interesting?

We know these signals are interference, but look similar to what we think might be produced from an extraterrestrial technology. They are narrow in frequency, much narrower than would be produced by any known astrophysical phenomena, and they drift in frequency with time, as we would expect because of the doppler effect imposed by the relative motion of the transmitter and the receiving radio telescope. Even though these signals are interference, detecting events with similar characteristics to what we expect from ET is a good indication that the first steps of our detection algorithms are working properly.

What's next?

These first results are tests of the algorithms we'll apply to all our observations of Kepler planets. During the coming weeks, we'll be posting more of our results as we process the nearly 50 TB of data we collected in early 2011.