A. Marino

A bus schedule drifts: if you don't check it, you'll miss your ride. Planets around other stars have the same problem – their crossings of the star's disk gradually shift. The ExoClock project pooled 30,000 observations from Earth and space to refine the schedule for 620 distant worlds. For 45% of the planets, transits were found to be off by hours.

In a dark corner of the Milky Way, a natural metronome is at work. Every 8196 seconds, about 2 hours and 16 minutes, X-ray light flares on the surface of a neutron star. The star EP J171159.4-333253 pulls gas from a neighboring star, and this gas, falling inward, accumulates on its surface.

The black hole MAXI J1810-222 behaves like a giant vacuum cleaner with a reverse valve: it pulls in matter, but some of it gets spat back out into space. This "backflow"—a stellar wind — had been spotted by astronomers before, but only as a blurry smudge in X-rays.