One of the closest stars in the constellation Puppis has a tight family of big planets. All three of them are between 10 and 20 times as massive as Earth. That makes them comparable to Neptune, one of the giants of our own solar system. And all three are much closer to their star than Earth is to the Sun.

HD 69830 is about 40 light-years away. The star is a bit smaller and lighter than the Sun, and less than two-thirds as bright. So unless you have really sharp eyes and really dark skies, you need binoculars to pick it out.

Astronomers discovered its planets 15 years ago.

The closest planet is just eight million miles away from the star — less than a tenth of the distance from Earth to the Sun. It’s the smallest of the planets as well. The farthest planet is about twice as heavy. And it’s still only a little more than half the Earth-Sun distance. That puts the planet near the inner edge of the star’s “habitable zone” — the region that’s most comfortable for life.

And there’s been plenty of time for life to take hold there. Estimates of the star’s age range up to about 10 billion years — twice the age of the Sun. So if life exists there, it could have been around since long before the birth of our own planet.

Puppis is low in the south at nightfall on these early April evenings. HD 69830 is at its northeastern corner. That puts it well to the left of Sirius, the brightest star in the night sky.

Script by Damond Benningfield

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