Ars Technica has a cautiously not-quite-freaked-out-yet look at what radio astronomers think might well be evidence of an extraterrestrial civilization:
According to Paul Glister, author of the Centauri Dreams website, the Italian astronomer Claudio Maccone and other astronomers affiliated with the search for extraterrestrial intelligence have detected “a strong signal in the direction of HD164595.” HD 164595 is a star of 0.99 solar masses about 95 light years from Earth, with an estimated age of 6.3 billion years. The system is known to have at least one planet, HD 164595 b, which is similar in size to Neptune and orbits its star in 40 days. Other planets may exist in the system as well.
The observation was made with the RATAN-600 radio telescope in Zelenchukskaya, in southern Russia, Glister reports. He cautioned that the evidence is very preliminary:
No one is claiming that this is the work of an extraterrestrial civilization, but it is certainly worth further study. Working out the strength of the signal, the researchers say that if it came from an isotropic beacon, it would be of a power possible only for a Kardashev Type II civilization. If it were a narrow beam signal focused on our Solar System, it would be of a power available to a Kardashev Type I civilization. The possibility of noise of one form or another cannot be ruled out, and researchers in Paris led by Jean Schneider are considering the possible microlensing of a background source by HD164595. But the signal is provocative enough that the RATAN-600 researchers are calling for permanent monitoring of this target.
[via Mr. Coates]