Astronomers have now found the first habitable rocky worlds around other stars – worlds that could have just the right temperatures to support life. So what happens next? To find out if these habitable worlds are inhabited, we need to know the global effects life can have on a planet, and crucially, which of those effects we could observe with our telescopes. We can gain some clues by looking at what life on Earth does today, but, so far, the planets we have found seem to have dramatically different environments compared to the modern day Earth. However, if we look millions, or even billions of years back through time, we start to find overlaps between conditions on these worlds and our own. The further back in time we look, the more alien our planet becomes. Strange environments, climates and weird forms of ancient life serve as perfect tools for figuring out many more of the unique “fingerprints” biology can leave behind on a planet for us to find. All of this takes us a step closer to finding extraterrestrial life – if it is there – on the un-Earth-like worlds around our nearest stars. In this talk Dr. O'Malley-James will discuss how we do this, what we might find, and what the future has in store for our quest to find other Earths.
(Image Credit: Dr. O"Malley-James)