Pitesky: Welcome to the NASA's PlanetQuest Podcast, Episode 1. This Podcast series will bring you regular updates and features about NASA's search for new planets and life around other stars. I'm Dr. Jo Pitesky, a scientist working on the SIM PlanetQuest mission. SIM PlanetQuest is a future space telescope designed to find Earthlike planets beyond our solar system.
Since the first planet was discovered around another star in 1995, there has been an explosion of discoveries of new solar systems. More than 150 new planets have been found so far, most of them gas giant planets, like Jupiter and Saturn. These planets are unlikely to support life as we know it. Roughly two-thirds of these planets have been discovered by planet-hunter Geoff Marcy and his team at UC Berkeley.
Marcy: "The discovery of planets around other stars is extraordinarily difficult. The problem, in a nutshell, is that a planet is about 1 billion times fainter than its host star, so the planets get lost in the glare of the host star.
"The real key is to find is to find planets that have a rocky, wet surface. It is that liquid water that provides the solvent for biochemistry -- the chemistry of life -- to flourish. So we're looking desperately for planets with a surface that can hold those pools of biochemistry that we think would eventually lead to complex life."
Pitesky: Marcy says the search for other Earths requires going into space, to avoid the distorting effects of Earth atmosphere. The SIM PlanetQuest mission, scheduled for launch in 2012, is the most powerful planet-hunting space telescope ever devised. Using two separated mirrors and combining their light with a technique known as interferometry, SIM PlanetQuest will able to detect planets nearly as small as Earth. These are the kind of planets that scientists believe have the most potential to support life.
Marcy: "What fraction of the twinkling lights you see at night have Earths? We're going to know the answer in ten years or less."
SIM PlanetQuest will also pave the way for future space telescopes, like Terrestrial Planet Finder, that will be able to directly image these distant worlds, and probe their atmosphere for the signatures of life. For NASA's PlanetQuest, this Dr. Jo Pitestky.
