A planet in a triple star system – a little like the Gliese 677 star system illustrated here – might be a good place to look for life MARK GARLICK/SCIENCE PHOTO LIBRARY

A red sun rises, huge and blazing hot in the sky. Then another sun rises, smaller and farther away. And then, quickly, a third distant sun. Morning has broken on the planet LTT 1445Ab, and it may be the easiest place outside our solar system to look for signs of life.

Astronomers used the Transiting Exoplanet Survey Satellite (TESS), a space telescope that looks for planets orbiting distant stars, …