Every space telescope launch story eventually has a chapter about mirrors, and usually it is the anxious kind. This one is the opposite: a nudge smaller than a sliver of a hair and the Wide Field Instrument now beats its own error budget by a wide margin. Nice to see the alignment engineers get the headline for once.

When two supermassive black holes merge, the gravitational waves can carry away momentum unevenly and give the newborn hole a shove. Theory has said so for decades; the fun part is the image of a monster black hole pacing back and forth through its own galactic centre like a pendulum. The evidence is statistical rather than a single smoking gun, which is exactly how these things usually start.

A palate cleanser from 10,000 Birds: species given the opinions their natural history implies. The cuckoo on parenting, the starling on native species, the hoatzin on personal hygiene. Silly, yes, but every joke is a real bit of biology, which is the best kind of silly.

Taylor's quiet point: economists have a decent recipe for a demand collapse, and much less of one when the shock hits what the economy can produce. Spending and rate cuts can prop up demand, but they cannot conjure up missing goods. A calm, useful frame for a lot of recent economic news.

Vermont spent fourteen years as its own republic, and some of the furniture from that era is still in use. Its county courts have had elected assistant judges continuously since then, and no other state does it. The kind of local oddity that only makes sense once you know the history.

A spiral staircase with no newel post, held together by wooden pegs, rising two full turns to a choir loft. Nobody recorded who built it, which has given legend plenty of room to work. Go for the carpentry; the mystery is a bonus.

Old TV collectors have the same problem as old radio fans: nothing on the air. Someone who worked in a 1990s transmitter control room solved it by building a miniature broadcast chain, waveform monitor and vectorscope included, mostly out of Raspberry Pis. Pure hobbyist joy, and a good tour of what a TV station actually had in its racks.

Homologation specials were road cars built in just enough numbers to let the racing version compete, and they are mostly extinct. Toyota's GR Yaris is the modern exception, and Mihail Rakovskiy has captured its odd three-door rally stance in bricks. Car MOCs live or die by their shaping, so look at the curves.

From the archive: Adrian Colyer working through Shapiro and colleagues' 2011 tour of state-based and operation-based replicated data types. The appeal is principled eventual consistency, with consensus pushed off the critical path rather than waved away. Still the paper people mean when they say CRDT.

Thomas Gainsborough wanted to paint landscapes but had portraits to pay the bills, so he brought the countryside indoors. Broken stones, moss, vegetables and shards of mirror, all set on a folding table and painted by candlelight. An eighteenth-century model railway enthusiast, minus the railway.

Aerocapture is the orbital equivalent of parking by scraping the curb: one pass through a planet's atmosphere to shed enough speed to stay, no big braking burn required. It has been on the wish list since before most flight software engineers were born, because guidance, heat shielding and orbital mechanics all have to be right at once, with no second try. Worth noticing how much of the problem is closed-loop control rather than hardware.

Long before distributed SQLite became a crowded category with funding rounds attached, one engineer bolted Raft onto SQLite over a weekend because a clustered system needed a little relational storage and no node wanted the job. This is the founder's own history, written partly to correct the record, and it's at its best on the unglamorous parts: what replicating every write actually costs and what a decade of users taught him.

Every database's isolation-level dropdown descends from this paper, which defined consistency in numbered degrees decades before the ANSI committee muddled the names. Adrian Colyer's write-up walks through what Gray and colleagues meant by each degree and where the later standard parted ways with them. A good reminder that the anomalies we still argue about were catalogued half a century ago.

The Apple Network Server was a Power Mac 9500 in a big case that Apple deliberately stopped from running Mac OS, then promised a ROM swap that everyone assumed was vapourware. Leaked preproduction ROMs proved otherwise, and here a hobbyist who discovered he owned one has packaged up the extensions needed to make it usable. Peak retrocomputing: archaeology, stubbornness and a working result.

SHIPtember asks builders for a spaceship at least a hundred studs long in a month, and the real treat is always the work-in-progress photos. This one is built around swirling vortex shapes that look as if they shouldn't be possible in LEGO, and the progress shots show they began as a chain of Technic frames. Technique first, spaceship second, which is exactly how it should be.

Newport is mostly known for gilded mansions, but out in the harbour sits a small lighthouse on an island with a military past of its own. It isn't even Rhode Island's oldest light, which makes its story more interesting rather than less. Bring binoculars; the all-round view across Narragansett Bay is the point of the climb.

Kyla's starting premise is hard to argue with: most career advice was written for an economy that has since moved out. Her new show with Vox asks what still holds and what the job market really looks like now, which is the kind of question she answers with data and calm rather than doom. A good fit for her style of explaining.

Ospreys are the raptor that made a full comeback in living memory, and a reservoir in a state park is exactly where you'd go looking. This guide comes from a young birder who has been at it since she wandered into a neighbour's feeder-filled yard at seven, and the affection shows. Nice photography, and a reminder that good local patch knowledge beats a long trip.

Low-tech Magazine makes a case for the humble handcart that is part history and part engineering argument: cheaper than a cart animal, easier than carrying, and it doesn't have opinions about where to go. The lead photo shows one fitted with a sail, which tells you what kind of read this is. Thoughtful, slightly contrarian, and oddly calming.

The Public Domain Review has gathered kite pictures from 1430 to 1929 and about a dozen countries, which turns out to be a tour of what each era thought a kite was for: play, war, science or simple showing off. The early ones sit somewhere between toy and military signal. Good browsing for an idle five minutes.

The quiet Sun is the bit solar physicists used to treat as wallpaper between the exciting active regions. Lift a telescope above most of the atmosphere on a balloon and the wallpaper turns out to be full of wiring. Worth noticing is the claim that surface twisting shapes the threads, which is the sort of cause-and-effect that coronal heating models have been short on.

A short one, but the rule here is that anything from the flight software crowd gets through. The call for abstracts went out earlier; now you can actually sign up to sit in the room where people swap war stories about patching code a hundred million kilometres away.

Keeping a lone positron alive is a bit like keeping a soap bubble in a room full of pins, so the endurance alone is impressive. The real point is precision: an isolated antiparticle you can watch for weeks is how you compare matter and antimatter closely enough to catch them disagreeing, if they ever do.

A proper field note from Ipoh, just down the road in birding terms, about a bird most people drive past without a second look. The interesting bit is the asynchrony: in one flock some birds are in full ginger breeding dress while others have barely started, and the species is now breeding further south in Perak than the books used to say.

Everyone who has watched Jepsen take apart a database has wondered whether it's luck. This Morning Paper write-up of Majumdar and Niksic's POPL 2018 paper says no: for the bugs that need only a few partitions in the right order, random exploration covers them with high probability in a modest number of tests. A nice bit of theory explaining something practitioners already trusted.

Doom gets the credit for squeezing miracles out of old hardware, but this author argues the city builders did something harder: simulate an economy, not just draw walls. A good read on the tricks game programmers used when every cycle was spoken for.

A war fought mostly over lumber, with militia, surveyors and a great deal of indignation, and settled by diplomats before it really got going. It explains why the top of Maine looks the way it does on a map, and why the largest county east of the Mississippi is up there at all.

Before Conan Doyle's dinosaurs became the template, a curator at the American Museum of Natural History was writing his own lost-world fiction with fresh science folded in. The essay is honest that the book is a slog, which is part of the fun: you get the history of the genre without having to finish the novel yourself.

A 1677 book of alchemy with no text at all, just engraved plates, which makes it the IKEA manual of the Philosopher's Stone. This copy belonged to Carl Jung, who naturally read a great deal into it. Look for the couple working side by side at the furnace: the 'humid way' was apparently a two-person job.

A sleepy amateur race in County Meath, a single phone line, and one man who had thought very carefully about both. Damn Interesting tells it at length and with obvious relish; it's one of those Irish stories that gets better every time it's told in a pub, and this is the long version.