Real estate markets have been pretty volatile in recent years. And that’s true even beyond Earth. Astronomers have been trying to figure out whether it’s possible for anything to live on planets orbiting red-dwarf stars. That’s important to know because red dwarfs are by far the most common stars in the galaxy. So if such star systems can support life, they could increase the Milky Way’s habitable real estate by a factor of 10.

Red dwarfs are the smallest, coolest, and faintest of all stars. But they’re also the longest-lived — the smallest could shine for trillions of years. And they account for three-quarters or more of all the stars in the galaxy.

Small, rocky planets similar to Earth should be common around such stars. And a large fraction of the planets could be in the best location — inside the habitable zone — the region where temperatures are just right for liquid water. That could mean tens of billions of potentially habitable worlds.

But there are lots of caveats. Because a red dwarf is so feeble, its habitable zone is narrow and close to the star. But red dwarfs produce powerful outbursts of X-rays, so any close-in planets would be zapped by radiation. And close planets would be locked so that the same side always faces the star, creating big differences in the daytime and nighttime temperatures.

So astronomers are still trying to figure out the real estate market around red-dwarf stars.
 

Script by Damond Benningfield

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