In the mid-1990s, astronomers made history when they began to find planets orbiting stars in the Milky Way. More than eight hundred planets have been found since then, yet none of them is anything like Earth and none could support life.
Now, armed with more powerful technology, planet hunters are racing to find a true twin of Earth. Science writer Michael Lemonick has unique access to these exoplaneteers, as they call themselves, and Mirror Earth unveils their passionate quest. Unlike competitors in other races, Geoff Marcy, Bill Borucki, David Charbonneau, Sara Seager, and others actually consult and cooperate with one another. But only one will be the first to find Earth's twin. Mirror Earth tells the story of their competition.
Science writer Lemonick (The Georgian Star) offers readers an informal and accessible view into the work of exoplaneteers : astronomers dedicated to searching out not just planets orbiting distant worlds, but Mirror Earths, Earth-like planets that might harbor life. It s not an easy task. Distance and stellar brightness relative to the exoplanets make them difficult to see directly. Astronomers must rely on techniques like measuring how much a star s brightness dims as a planet passes in front of it, or how much the star appears to wobble due to the gravitational attraction between it and an orbiting planet. Lemonick introduces planet-hunting pioneers like mild-mannered Bill Borucki, indefatigable Geoff Marcy, former cosmologist Sara Seager, and nurse-turned-astrophysicist Debra Fischer, revealing personalities as well as research frustrations and successes. Exoplanets, it turns out, aren t really rare at all; they re just nothing like what we expected to find. Most are more like hot Jupiters than cozy Earths. Discoveries also raise questions about what habitable means; after all, there s no rule that says life must be Earth-like. Today s exoplanet discoveries are building the foundation for learning just what kind of life is possible out there. B&w illus.