Lucky seven
Astronomers have discovered seven Earth–sized planets orbiting a star called TRAPPIST–1.
“The discovery gives us a hint that finding a second Earth is not just a matter of if, but when,” Thomas Zurbuchen, associate administrator of the Science Mission Directorate at NASA Headquarters. Zurbuchen called it a “major step forward” towards the goal of answering the very big question: Is there life on other worlds?
About star TRAPPIST–1
The TRAPPIST–1 star, an ultracool dwarf, has seven Earth–size planets orbiting it. The researchers believe that TRAPPIST-1f in particular is the best candidate for supporting life. It’s a bit cooler than Earth, but could be suitable with the right atmosphere and enough greenhouse gases.
What are exoplanets?
Exoplanets are planets that oribit a star other than our own sun. In 1995 two Swiss astronomers discovered the first exoplanet, 51 Pegasi b. NASA says almost 3,500 exoplanets have been confirmed in the universe.
Earth’s seven sisters
Seven small planets whose surfaces could harbour liquid water have been spotted around a nearby dwarf star. If such a configuration is common in planetary systems, our Galaxy could be teeming with Earth–like planets.