Astronomers have found more than 750 alien planets to date, and NASA’s Kepler Space Telescope has flagged 2,300 additional “candidates” awaiting confirmation by follow-up studies. This haul has not yet included an Earth-like exoplanet — one that’s the size of our planet and orbits at the right distance from its star to support liquid water and, possibly, life as we know it.
But that could change soon, according to Shawn Domagal-Goldman, a researcher at NASA Headquarters in Washington, D.C. who specializes in exoplanet biology.
“I believe Kepler will find a ‘Goldilocks planet’ within the next two years,” Domagal-Goldman said in a statement. “We’ll be able to point at a specific star in the night sky and say ‘There it is — a planet that could support life!’”
They’re planning on both a probe (Finesse) and an observatory (Tess) using a method called orbital transit spectroscopy, taking advantage of the light reflected off of the planet’s atmosphere to determine its chemical composition. The will measure the spectra when the planet is in front of – and then behind – its star. Doing so will allow it to filter out the spectrum of its parent star, leaving only that of the planet behind.
Of course, I always take these claims that “we’ll find an earth-like planet within X number of years” with a grain of salt … but the fact is that we’ve made tremendous leaps in the last 20 years in the number and type of exoplanets we’ve discovered. It’s likely, given our findings, that we’ll soon get a much better idea about the frequency of earth-like planets in our own neck of the woods.