In distant planet's fluorescent glow, a new way to look for life
For the first time, astronomers detected the fluorescent signature of an exoplanet's atmosphere. Fluorescence can give scientists clues about processes that might make a planet habitable for life.
For the first time, astronomers have detected gas glowing like a fluorescent bulb in the atmosphere of a planet orbiting a distant star.
Researchers have had glimpses of the atmospheres of so-called exoplanets before, but never in this way. The fluorescent signature of HD 189733b, a Jupiter-size planet in the faint constellation of Vulpecula, could help astronomers explore exoplanets in more detail – including ways that help them in the search for life elsewhere in the galaxy.
HD 189733b is no candidate for life. But the techniques used to study fluorescence in the highest reaches of its atmosphere will help scientists tease out information that, on more Earth-like planets, could be crucial to life. These include the presence and strength of a planet's magnetic field and processes driving changes in the planet's atmosphere, researchers say.
Moreover, the work can be done with modest-size ground-based telescopes, not just mountaintop behemoths. As a result, more telescopes can be employed to try to uncover the processes at work on exoplanets, accelerating the pace of discovery, says Mark Swain, an astronomer who led a team of researchers conducting the measurements.
The team's work "is tremendously exciting," says Seth Redfield, an astronomer at Wesleyan University in Middletown, Conn. So little is known about individual exoplanets that any new window on these distant worlds is important, he continues.