Astronomers find three new planets in Gliese 667's habitable zone
Gliese 667 C is a well studied triple-star system in the constellation Scorpius, and at 22.1 light years away, it's relatively close to Earth. Previous studies of the star system revealed that it contained only three planets in all, with only one of them in the habitable zone (the region around a star that supports planets with liquid water on the surface). But new research from astronomers at the European Southern Observatory (ESO) shows that the system contains seven total planets, with three inside the habitable zone.
Using multiple precision telescopes and the High Accuracy Radial velocity Planet Searcher (HARPS)—a high precision spectrograph on ESO's 3.6-meter telescope—the ESO astronomers gathered and evaluated new data on the Gliese 667 C system, which they then compared to existing data.
As lead researcher Mikko Tuomi of the University of Hertfordshire, UK, explained:
“We knew that the star had three planets from previous studies, so we wanted to see whether there were any more... By adding some new observations and revisiting existing data we were able to confirm these three and confidently reveal several more. Finding three low-mass planets in the star’s habitable zone is very exciting!”
What's even more fascinating is that the number of habitable planets in our galaxy may be much larger than previously thought if we consider that there may be other systems out there with not just one habitable planet (like our own system), but with several habitable planets just like the Gliese 667 C system.
Not only that, but Gliese 667 C is actually pretty close to Earth and believe it or not, but it's close enough that it might actually be possible that some of us may live to see the results of an actual mission to Gliese 667 C and its planets: NASA has a Skunkworks project called "Eagleworks" whose purpose is to enable interstellar spaceflight by the end of the century.
To learn more about this discovery be sure to check out the full details at the ESO.