For now, the planet is unceremoniously called Proxima Centauri b. It zips around its namesake star every 11.2 days, and is likely locked in place—like the moon, which always shows the same face to Earth. It’s at least 1.3 times as massive as our planet, and based on its likely size, astronomers think it is rocky. Its home star is only .15 percent as bright as the sun, so the planet isn’t as scorched as you might expect, given its tight orbit. Instead, it circles around in a sweet spot that might allow for liquid water on its surface. “It’s in about the same position in the habitable zone of Proxima as the Earth is in the habitable zone around the sun,” says James Kasting, an astronomer at Penn State who was not involved in the new finding.

Viewed from the planet’s surface at midday, Proxima Centauri would be a dark red, and the planet’s atmosphere, if it has one, could make its sky a mixture of purples and oranges instead of blues. If plants have colonized its surface, their leaves might be crimson instead of green. The planet’s discoverers have nicknamed it “Pale Red Dot.”

Though this biographical sketch is intriguing, scientists caution that they don't know exactly what the planet looks like. “At the moment, we have no idea what the makeup of the planet is. Does it have a magnetic field to shield itself? Does it have an atmosphere? We have no idea,” cautions James Jenkins of the University of Chile, another Scotsman working in the Southern Hemisphere and a member of the discovery team.

Still, studies of several hundred other distant worlds can help scientists make some informed guesses. If it is tidally locked the way the moon is, the huge difference in temperatures from day to night could make it difficult to maintain liquid water around the whole planet, Kasting says. It's possible water flows in a ring around the planet's day side; if so, that extra mass could stretch the planet into a slightly oval shape. But it's also possible that a thick atmosphere or a deep ocean could distribute heat around the whole world.

Proxima Centauri showers the planet in radiation that could blow away its atmosphere and water, but it might have formed farther from its star than it is now, at a distance that would have protected the planet during the star's turbulent youth. The presence of water and an atmosphere depends on the planet's history, and that's a story we don't know yet. Scientists disagree about the star's age, but think it is probably around 4.3 billion years old, a few millennia younger than the sun, and the Earth.

Could life have arisen there in that span of time? People who are alive today might live to find out. In the next two decades, a new class of giant telescopes will be built atop barren mountains, where they will begin soaking up starlight. Observatories like the European Extremely Large Telescope and the Thirty Meter Telescope could scrutinize the wee world’s atmosphere, separating the starlight that passes through it to find telltale chemical signs of life.