Astronomers have developed a new method to probe the atmospheres of extrasolar planets, which should greatly expand the search for planets that have the right temperature and composition for life.
The technique allowed researchers to precisely calculate the mass of a planet named Tau Bootis b for the first time since its discovery 15 years ago.
ďThe coolest thing about this technique is we basically can now see the planet itself and its orbital movement,Ē said astronomer Simon Albrecht of MIT, who co-authored a paper describing the method and the Tau Bootis b findings, which appeared June 28 in Nature.
Researchers have several ways of learning about exoplanets. One of the most common and useful methods is used by the Kepler space telescope, which watches to see if the brightness of a star periodically dips, indicating that a planet is passing in front and eclipsing its light. When the exoplanet is just at the starís edge, starlight can seep through the planetís atmosphere, carrying a fingerprint of the atmospheric composition when it arrives at telescopes on Earth. Researchers can also sometimes block out a starís light and directly image an exoplanet, but only when it is farther from its star than Pluto is from our sun.