Asteroid 2024 BX1 entered Earth's atmosphere over Germany 21 Jan 2024

[Astronuc]

Asteroid 2024 BX1 that exploded over Berlin was fastest-spinning space rock ever recorded
https://www.livescience.com/space/a...was-fastest-spinning-space-rock-ever-recorded

Scientists have calculated the rotational speed of asteroid 2024 BX1, which exploded over Berlin earlier this year, by letting it trail in images of the sky. It turns out, 2024 BX1 was spinning faster than any other near-Earth object ever seen.

The space rock, dubbed 2024 BX1, turned into a fireball and exploded over Berlin in the early hours of Jan. 21. Although small asteroids on collision courses with Earth are typically detected only when they crash into the atmosphere, scientists spotted this one roughly three hours before impact.

That's not the only way 2024 BX1 was unusual, according to a paper published to the preprint database arXiv on April 5. Researchers think the asteroid, which was traveling 31,000 mph (50,000 km/h), was rotating once every 2.6 seconds — the fastest spin ever seen for an asteroid.

Visualisation of the trajectory and impact of asteroid 2024 BX1 on 21 January 2024
https://www.esa.int/ESA_Multimedia/...mpact_of_asteroid_2024_BX1_on_21_January_2024

Asteroid 2024 BX1 left a rare type of meteorite
https://www.astronomy.com/science/asteroid-2024-bx1-left-a-rare-type-of-meteorite/

2024 BX1’s meteorite fragments were hard to differentiate from the natural rocks in the area. While meteorites usually have a glossy black crust of glass, the recently crashed meteorites are coated with glass that is translucent, instead. “We only spotted the meteorites after a Polish team of meteorite hunters had identified the first find and could show us what to look for,” said Peter Jenniskens, a meteor expert at the SETI Institute.

Aubrites, named after Aubrés, a village in France where the first such meteorite fell in 1836, is a type of achondrite. These meteorites don’t contain chondrules — round mineral inclusions found in the most common types of meteorites, called chondrites. Instead, aubrites come from parent bodies that underwent significant melting. Some studies suspect aubrites might have formed in magma oceans in a region around the distance of Earth from the Sun.

Achondrites have a gray, granitelike appearance and can easily be mistaken for rocks found on Earth. These meteorites contain magnesium silicates enstatite and forsterite, but not much iron, according to Christopher Hamann, a meteorite researcher at the Museum für Naturkund involved with the classification.