The eerie silence? SETI discussion (video).
A technologically advanced extraterrestrial civilization could likely detect life on Earth if such beings exist. Life on Earth would be detectable in our planet’s atmospheric spectral lines for over a billion years.
Most of our atmospheric oxygen is due to life, and can be observed over interstellar distances — across thousands of light-years. Over this long time, many stars have swept near our solar system and Earth.
So, if extraterrestrial intelligence on such nearby planets did send probes to remotely observe our planet, where in the Solar System should we look to find evidence of their past visitation?
Jump into this topic with a 40-minute-long panel video between astrophysicist Dr Brian Keating, Prof. Paul Davies, SF author Dr. James Benford, and Mat Kaplan of the Planetary Society.