First Earth-sized planets confirmed outside solar system

A local scientist working on NASA’s Kepler project helped discover the first Earth-sized planets orbiting a sunlike star outside of our solar system.

The two planets are the smallest yet discovered around a star like our sun.

“I am extremely excited,” said Villanova professor Andrej Prsa, who is on one of the Kepler teams that helped confirm the finding. “It means that the technology and the primary purpose of the mission are completely within grasp.”

 

These two planets are rocky, like Earth, but too close to their stars to support any kind of life.

But Prsa said the finding proves the Kepler telescope is sensitive enough to detect Earth-sized planets if they exist in the hospitable zone, sometimes called the “Goldilocks zone,” where it is neither too cold nor too hot to support life.

Finding such planets is Kepler’s main mission.

The space telescope detects planets by measuring dips in the light from more than 150,000 stars. Those dips signal that a body, perhaps an orbiting planet, has passed between the stars and the telescope.

Derrick Pitts, chief astronomer at The Franklin Institute, said the discovery shows just how accurate the telescope is.

“It’s as if you’re standing 200 feet in front of a set of car headlights, and a mosquito flies in front of the car headlight, could you possibly see the drop in brightness from the headlights?” Pitts said. “It’s amazing that the engineers can actually make such measurements.”

The finding doubles the number of known Earth-sized planets in the universe. Earth and Venus are the other two.