A recurring cloud over the Martian volcano Arsia Mons turns out to freeze straight out of water vapour, with no dust grain to seed it, a process never before caught in any planetary atmosphere. We also look at the first interstellar detection of fully deuterated methanol by ALMA, a white dwarf that may be feeding on a planet born after its star died, and three quiet dwarf galaxies near M101 found in public archive data by a first year undergraduate.

Hubble ultraviolet spectra of 29 metal-poor massive stars show their winds slowing far more sharply than models assumed, which matters for how we read JWST's puzzling early galaxies. Yale meteorite work finds the outer Solar System's first planetesimals were built from 83 to 92 per cent chondrules rather than icy dust, and a new simulation suggests the black holes that wandered away from their galaxy's centre carry the clearest record of its past. We close with NGC 4698, a Virgo spiral rotating out of step with itself.