Two of the eight planets of the solar system highlight the western evening sky. Venus is the brilliant “evening star.” Saturn is below it. It looks like a fairly bright star, although not nearly as bright as Venus.

A bunch more planets lurk in the background. They’re in the star system Trappist-1. It’s in the constellation Aquarius, right next to Saturn’s current location.

The star is a red dwarf. It’s only a fraction the size and mass of the Sun. In fact, it’s just about as puny as it’s possible for a true star to be.

Trappist-1 has seven known planets. Only our own solar system is known to have more. All seven planets are extremely close to the star – no more than a few million miles away. But several of them are in the star’s habitable zone – the region where conditions are most comfortable for life. And the system is about three billion years older than our own, so there’s been plenty of time for life to evolve there.

In fact, a project that’s looking for extraterrestrial civilizations took a look at the system. Scientists wondered whether more than one planet might be inhabited, and whether they might talk to each other via radio. We see the system edge-on, so any transmissions between planets might leak out in our direction. So the project tried to “eavesdrop” on the conversations.

The search came up empty. So if the planets of Trappist-1 are inhabited, the folks there don’t seem to be talking to each other.

Script by Damond Benningfield