So far, astronomers have found thousands of planets orbiting far-away stars, ranging from hot Jupiters to super-Earths. How do we find these distant worlds? EXOPLANETS — Discovering New Worlds describes the two main methods astronomers use: the radial velocity method studies minute “wobbles” of stars, and the transit method detects eclipsing planets from flickers in a star’s brightness.
Discovering planets is one thing; finding life on those worlds is the next challenge.
What about moons in our own Solar System? Could they support life? What these worlds reveal could help in the search for life beyond the solar system. No extraterrestrial life has been found anywhere else — yet. The possibility of finding life drives our extrasolar planet searches. What if that life is intelligent? Has it tried to contact us?
EXOPLANETS — Discovering New Worlds speculates on the existence of such life, and points out nearby civilizations may already know about us — from our radio and TV broadcast signals. Someday, we may find those societies and marvel at their technological achievements.