Jennifer A. Burt

The TESS telescope, usually hunting for planets around other stars, spotted 24 dimmings around RZ Psc. These were comets — chunks ranging from 1 to 7 km in size, transiting the star's disk. Like a distant searchlight momentarily blocked by a tiny pebble: the deeper the shadow, the larger the object.

Jupiter is a colossal ball of gas that sits five times farther from the Sun than Earth. Now imagine a similar ball, but around another star, at a distance tens of times greater. These are called cold Jupiters, and they remain a puzzle: how did they get there? Astronomers studied four such planets around distant stars.

Around the star Epsilon Indi, visible to the naked eye from the Southern Hemisphere, orbits a planet the size of Jupiter. The temperature there is like a good freezer: minus 200 degrees Celsius. The James Webb Space Telescope has for the first time directly imaged it and measured the light the planet emits in the thermal range.