Earth's Closest Star Has A Potentially Habitable Planet Orbiting It, Scientists Say

A team of scientists from around the world announced Wednesday that the closest star to Earth (besides our sun) has a planet orbiting it that could potentially harbor life.

The rocky planet is at least 1.3 times as massive as Earth, orbits the star once every 11 days and is close enough to the star that water could exist on the planet, according to an announcement from the European Southern Observatory.

The planet, named Proxima b, orbits the star Proxima Centauri, which is just four light years away from Earth. That means a spacecraft from Earth could, theoretically, one day explore the star and its just-discovered planet.

"This rocky world is a little more massive than the Earth and is the closest exoplanet to us — and it may also be the closest possible abode for life outside the Solar System," the announcement said.

Proxima b orbits the star about 4.35 million miles away from the star — more than 20 times closer than Earth orbits the sun. But this star doesn't burn near as bright as the sun does, and so this planet only receives about two-thirds the amount of heat and light that Earth does.

That still puts Proxima b in the so-called "Goldilocks Zone," a name scientists have given to the area surrounding a star where a planet could hold liquid water, believed to be a key ingredient for supporting life.

So, does this planet have water on it?

That's, obviously, the million-dollar question scientists would love to answer but can't right now.

The estimated temperature of the planet is suitable for liquid water to flow on its surface. But because the planet is so close to its sun, it receives intense radiation. Without a strong atmosphere like Earth has, that radiation may have evaporated any water that ever existed on its surface.

"So as far as we know, Proxima b could resemble Mercury, with no water and no atmosphere," reads a website put together by the team of scientists researching the planet, "or it could be covered by deep oceans beneath a thick atmosphere."

Image: Artists rendering of Proxima b, via European Southern Observatory