It’s been quite a week for asteroid 2024 YR4, which looked like it was going to live up to its “city killer” moniker only to be demoted to a fraction of a percent risk of hitting us when it swings by our neighborhood in 2032. After being discovered at the end of 2024, the 55-meter space rock first popped up on the (figurative) radar a few weeks back as a potential risk to our home planet, with estimates of a direct strike steadily increasing as more data was gathered by professional and amateur astronomers alike. The James Webb Space Telescope even got in on the action, with four precious hours of “director’s discretionary” observation time dedicated to characterizing the size and shape of the asteroid before it gets too far from Earth. The result of all this stargazing is that 2024 YR4 is now at a Level 1 on the Torino Scale of NEO collision risk, with a likely downgrade to 0 by the time the asteroid next swings through again in 2028. So, if like us you were into the whole “Fiery Space Rock 2032” thing, you’ll just have to find something else to look forward to.
On the other hand, if you’re going to go out in a fiery cataclysm, going out as a trillionaire wouldn’t be a bad way to go. One lucky Citibank customer could have done that if only an asteroid had hit during the several hours it took to correct an $81 trillion credit to their account back in April, a mistake that only seems to be coming to light now. You’d think a mistake 80% the size of the global economy would have caused an overflow error somewhere along the way, or that somebody would see all those digits and think something was hinky, but apparently not since it was only the third person assigned to review the transaction that caught it. The transaction, which falls into the “near-miss” category, was reversed before any countries were purchased or fleets of space yachts were commissioned, which seems a pity but also points out the alarming fact that this happens often enough that banks have a “near-miss” category — kind of like a Broken Arrow.
We all know that near-Earth space is getting crowded, with everyone and his brother launching satellite megaconstellations to monetize our collective dopamine addiction. But it looks like things are even starting to get crowded around the Moon, at least judging by this lunar photobomb. The images were captured by the Lunar Reconnaisance Orbiter, which has been orbiting the Moon and studying the landscape for the last 16 years but stretched its capabilities a bit to capture images of the South Korean Danuri. The two probes are in parallel orbits but opposite directions and about 8 kilometers apart at the time, meaning the relative velocity between the two was an unreasonably fast 11,500 km/h. The result is a blurred streak against the lunar surface, which isn’t all that much to look at but is still quite an accomplishment. It’s not the first time these two probes have played peek-a-boo with each other; back in 2023, Danuri took a similar picture when LRO was 18 kilometers below it.
We don’t do much air travel, but here’s a tip: if you want to endear yourself to fellow travelers, it might be best to avoid setting up a phone hotspot named “I Have a Bomb.” That happened last week on American Airlines flight 2863 from Austin, Texas to Charlotte, North Carolina, with predictable results. The prank was noticed while the flight was boarding, causing law enforcement officers to board the plane and ask the prankster to own up to it. Nobody volunteered, so everyone had to deplane and go back through screening, resulting in a four-hour delay and everyone missing their connections. We’re all for fun SSIDs, mind you, but there’s a time and a place for everything.
And finally, we wanted to share this fantastic piece from Brian Potter over at Construction Physics on “Why it’s so hard to build a jet engine.” The answer might seem obvious — because it’s a jet engine, duh — but the article is a fascinating look at the entire history of jet propulsion, from their near-simultaneous invention by the principal belligerents at the end of World War II right through to their modern incarnations. The article is an exploration into the engineering of complex systems, and shows how non-obvious the problems were that needed to be solved to make jet engines practical. It’s also a lesson in the difficulties of turning a military solution into a practical commercial product. Enjoy!