Geomagnetic reversals have been suspected of extinction crimes for decades without ever quite being convicted. This new work finds a tight cluster of flips lining up with an extinction and a flood-basalt eruption, which is still circumstantial, but it's a much nicer alibi problem for the defence.

Mars is usually filed under geologically retired, so it is nice to see the planet's great canyon system still shifting. Worth noticing how far the evidence has to stretch: billions of years after it formed, the 4,000-kilometre scar is apparently not finished.

Textbook transit diagrams treat planets as tidy black discs, which is a fine approximation until a telescope is good enough to notice the edges disagree. Webb now is. The puffed-up evening side of this hot gas giant is the sort of detail that turns a dot into weather.

Type Ia supernovae gave us dark energy in the first place, so it is fitting that a big pile of them is now poking at whether it holds still. This joins a growing set of results nudging against the cosmological constant. Not a revolution yet, but the error bars are getting interesting.

Every Martian summer morning a cloud the length of a small continent unfurls west of Arsia Mons, then vanishes by lunch, and for decades nobody could make the atmospheric models reproduce it. A new paper offers a mechanism that textbook cloud physics hasn't had a real example of before. Weather that keeps a schedule better than most airlines.

The near side is all dark lava seas, the far side is pale and cratered, and nobody has had a really satisfying reason why. Now there are actual rocks from the far side to argue with, which beats modelling in the dark. Notice that Earth itself is the culprit here: the tidal tug of the home planet may have stirred the young Moon's interior unevenly.

Euclid was built to map the dark universe across billions of light years, so it is quietly charming that it also tripped over a fresh snowball in our own backyard. Survey telescopes that stare at everything tend to find things nobody asked them to; this is that tradition, continued.

Remember the May boom that rattled windows and startled birds all along the Cape. MIT's Haystack people and colleagues pooled an unusually large pile of ground and satellite data to work out where the rock came from. Nice local detective story with a solar-system-sized map at the end.

A pretty picture with a geology puzzle attached. The yardangs on Mount Sharp are the wrong colour and their layers tilt oddly, and one idea is that they are ancient volcanic ash. Curiosity plans to drive up and poke them with its arm in 2027, which counts as a cliffhanger by rover standards.

Japan's sample-return team, the people behind Hayabusa and Hayabusa2, is going after a moon of Mars this time. Phobos is too small to orbit in the normal sense, so landing looks more like a careful bump than a touchdown. The capsule is due back around 2031.

OSIRIS-REx brought back pieces of Bennu, and now the lab has explained a long-standing puzzle from orbit. It is a good example of sample return earning its keep: you can measure a rock from a spacecraft, but you need it on a bench to see why it behaves the way it does.

The one conference where the people who write the code that keeps spacecraft alive compare notes, and the talks go up on YouTube afterwards for the rest of us. Registration just opened and the call for abstracts is live, so if a kernel person ever wanted an excuse to talk to the JPL crowd, this is it.

Textbooks insist there are no green stars, and for good physical reasons. This one cheats: it swallowed pieces of its old planetary system, and the sodium they left behind soaks up orange light. The survey also found pink and yellow white dwarfs nearby, so the night sky is a little more colourful than advertised.

A buried crater off the English coast that geologists voted against in 2009 turns out to be the real thing after all. The clinching evidence came from shocked quartz in old oil-well rock cuttings, which is a lovely example of industrial leftovers settling a scientific argument. Close enough to the Dutch coast to count as neighbourhood news, give or take 45 million years.

Opportunity's distance record stood as a monument to plucky persistence; Perseverance matched it in about a third of the time. The interesting part is why: the rover drove itself with autonomous navigation for over 90 percent of the trip. A nice milestone for onboard software as much as wheels.

A cosy detective story: one of the earliest recorded cases of space weather affecting technology turned out to be dated before the railway in question existed. Physicists checked timetables and magnetometer records like historians, and the case closes neatly.

Amateur astronomers pointed a telescope at a well-photographed patch of sky for about a hundred hours and found things nobody had catalogued. Fitting timing for late October. Look for the faint blue wisps; those are the new arrivals.