SETI Institute Principal Investigator
“We now have more than our own solar system to study,” says astronomer Alan Penny, “and already we have discovered planetary systems very unlike our own. Our theories of planet formation are in the process of major changes.” Unlike other planet searches that now focus on small parts of the sky, Penny examines the entire sky for Jupiter-sized planets around nearby stars. He is also exploring the technologies of future space telescopes for large-scale surveys for Earth-like planets, to supplement the already planned Kepler and Terrestrial Planet Finder (TPF) missions. Not content to know whether terrestrial planets exist around other stars, Penny’s long-term planning will help understand the range of types of Earth-sized planets - if they exist.
In the meantime, TPF will be able to study the atmospheres of these extrasolar planets. “If an Earth-like planet has a large amount of oxygen in its atmosphere, then it is probably due to biological activity,” Penny explains. “It is possible that this could be the first discovery of active life outside the Earth. Such a discovery would be a major step in planetary and atmospheric science, in the biology of the origin of life, and a step to answer the question of ‘Are we alone?’”
- SETI Institute Explorer, Special Edition 2005