In last two years we had reported "Alien Laser Signal Gliese Coming From A Habitable Planet, Star System?", "Possible Extraterrestrial Alien Signal Received Says, NASA-SETI"
NASA-SETI : No one knows for sure what caused this signal. There is a slight possibility that it just might originate from an extraterrestrial intelligence. Published - 2011and "US Military Pays SETI To Check Kepler-22b For Aliens'.
Now in latest development, according to seti.berkeley.edu website "We've started searching our Kepler SETI observations and our analyses have generated a few 'hits' "but all are undoubtedly examples of terrestrial (Earth) radio frequency interference (from our own satellites) [Check down below SETI clarification: U-turn update].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 (from our own satellites).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.
Above signal looks similar to NASA-SETI 2011 signal 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.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.
Source: http://seti.berkeley.edu/kepler-seti-interference
Earlier SETI tried to downplay the finding by branding it as "undoubtedly earthly interference" but after coming under-fire, now in their latest update they said "we had not stated as definitively and absolutely as possible that these signals are just interference (Earthly)." So they declared its highly likely signals are of Extraterrestrial in nature.