Proxima Centauri b...

Breakthrough Starshot concept would use a giant Earth-based laser array to accelerate a space sail to a significant fraction of the speed of light. Destination: Proxima Centauri b? (Credit: Breakthrough Initiatives)
Image Source: Astronomy Magazine

Topics: Astronomy, Astrophysics, Exoplanets, Solar Sail, Space Exploration

The hunt for exoplanets has, in some ways, been about the hunt for an Earth-like planet - something warm where water could exist. Headlines tout each discovery as "the most Earth-like planet yet." Many of these planets are far away.

But a new discovery published August 24 in Nature hits closer to home, with an Earth-like planet in the habitable zone of a star. Whats more, that star is Proxima Centauri, only 4.24 light-years away. That means that there is no solar system that will be closer to Earth in our lifetimes.

And so far, the exoplanet, named Proxima Centauri b, is shaping up to be quite Earth-like, roughly the mass of our planet and in just the right place where, if it has an atmosphere, liquid water could exist on the surface.

This is as in our backyard as it gets.

Astronomy: The exoplanet next door
John Wenz is an associate editor at Astronomy magazine