It's not a matter of if, but when.
Those words were spoken by Thomas Zurbuchen, associate administrator of the Science Mission Directorate at NASA, at today’s highly-anticipated NASA press conference. NASA held the conference today to announce the discovery of a surprising set of exoplanets in a nearby system potentially capable of sustaining life. Seven Earth-sized exoplanets orbiting the ultracool dwarf star Trappist-1, found roughly 40 light-years away in the constellation Aquarius.
The seven newly discovered exoplanets are so close together that anyone standing on the surface of one of the planets would have a “wonderful view” of the other six planets akin to our own view of the Moon.
The discovery of these exoplanets was made with the space-based Spitzer telescope, which can measure the brightness and composition of objects at much higher level of precision than other telescopes. The researchers stated this is the most exciting discovery made with the Spitzer telescope to date. According to Zurbuchen, this is because these planets are the best leads so far in the search for life outside of our own solar system:
This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life. Answering the question ‘are we alone’ is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal.
Three of these new exoplanets are in the “Goldilocks Zone” around their stars, which means they are neither too cold nor too hot to support life and/or liquid water. The three planets are: Trappist-1F, which could possibly host an aqueous environment and receives the same amount of sunlight as Mars; Trappist-1E rocky, same size as Earth and receiving a similar amount of sunlight as Earth; and Trappist-1G - largest planet in the system, with a radius roughly 13% larger than Earth and which receives the same amount of sunlight as the asteroid belt between Mars and Jupiter.
The researchers described this new system as a “laboratory” for studying exoplanets surrounding relatively cool stars. Going forward, the team hopes to use the James Webb telescope to further study the chemical composition of these new exoplanets in an attempt to identify elements which might support known forms of life. According to Sara Seager, professor of planetary science and physics at MIT, this discovery gives the researchers hope that “many more life-bearing worlds out there waiting to be found.” Fingers crossed.