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Meteor Rumbles Over Houston, as Six-Pound Fragment Crashes Into a Texas Home

"It is the talk of the town today — the loud boom, the flash of light in the sky experienced by a lot of folks across the Houston area this afternoon," says a local Texas newscaster. "And then there was this — a home in northwest Harris county hit by something that crashed through their roof." Travelling at very high speed, the six-pound meteorite crashed through their roof and through their attic, crashing again through the ceiling of the floor below. It then bounced off the floor, hit the ceiling again — and then fell onto the bed. CBS News reports: NASA said in a social media post that the meteor became visible at 49 miles above Stagecoach, northwest of Houston, at 4:40 p.m. local time. The meteor moved southeast at 35,000 miles per hour, breaking apart 29 miles above Bammel, just west of Cypress Station, NASA said. "The fragmentation of the meteor — which weighed about a ton with a diameter of 3 feet — created a pressure wave that caused booms heard by some in the area," NASA said in the post. Across the Houston area, residents described hearing a low, rumbling sound that many compared to thunder, even though the skies were clear, according to CBS affiliate KHOU. Earlier this week, an asteroid weighing about 7 tons and traveling at 45,000 mph traveled over multiple states. And last June, a bright meteor was seen across the southeastern U.S. and exploded over Georgia, creating similar booms heard by residents in the area.

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« Hors de portée » : des physiciens ruinent les ambitions intersidérales d’Elon Musk

elon musk espace

Pour s’installer autour d’une autre étoile que le Soleil, il faut d’abord la rejoindre. Un groupe de physiciens nous explique qu’accélérer un vaisseau à une vitesse suffisante pour arriver vers l’étoile la plus proche de nous en un temps raisonnable demanderait une énergie comparable à celle consommée par l’humanité entière pendant des siècles, voire des millénaires. La perspective d’aller s’installer en orbite d’Alpha du Centaure peut sembler séduisante, mais elle est hors de portée.

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NASA's Hubble Unexpectedly Catches Comet Breaking Up

NASA's Hubble Space Telescope unexpectedly captured a rare, early-stage breakup of comet C/2025 K1 (ATLAS) just days after it first began disintegrating. Phys.org reports: "Sometimes the best science happens by accident," said co-investigator John Noonan, a research professor in the Department of Physics at Auburn University in Alabama. "This comet got observed because our original comet was not viewable due to some new technical constraints after we won our proposal. We had to find a new target -- and right when we observed it, it happened to break apart, which is the slimmest of slim chances." Noonan didn't know K1 was fragmenting until he viewed the images the day after Hubble took them. "While I was taking an initial look at the data, I saw that there were four comets in those images when we only proposed to look at one," said Noonan. "So we knew this was something really, really special." Hubble caught K1 fragmenting into at least four pieces, each with a distinct coma, the fuzzy envelope of gas and dust that surrounds a comet's icy nucleus. Hubble cleanly resolved the fragments, but to ground-based telescopes, at the time they only appeared as barely distinguishable, bright blobs. [...] "Never before has Hubble caught a fragmenting comet this close to when it actually fell apart. Most of the time, it's a few weeks to a month later. And in this case, we were able to see it just days after," said Noonan. "This is telling us something very important about the physics of what's happening at the comet's surface. We may be seeing the timescale it takes to form a substantial dust layer that can then be ejected by the gas." The findings have been published in the journal Icarus.

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Asteroid Ryugu Has All of the Main Ingredients For Life

Samples from the asteroid Ryugu contain all five nucleobases -- the key building blocks of DNA and RNA. "This strengthens the idea that asteroids may have brought the ingredients for the first living organisms to Earth long ago," reports New Scientist. From the report: Japan's Hayabusa 2 spacecraft visited Ryugu in 2018, where it shot two projectiles -- one small and one large -- into the surface of the asteroid and collected the resulting debris. It arrived back at Earth with the samples in 2020 and researchers have been analyzing these in detail ever since. Yasuhiro Oba at Hokkaido University in Japan and his colleagues examined two samples, one from the asteroid's surface and one comprised of subsurface materials excavated by the projectiles. In both, the team found all five primary nucleobases, which are the compounds that make up the nucleic acids DNA and RNA when combined with sugars and phosphoric acid. This isn't the first time that nucleobases have been found in asteroid samples: they have been seen in meteorites, too, and in samples from the asteroid Bennu. The researchers did find different abundances of the various nucleobases among the various samples, though, which hints that these compounds might be useful for tracing asteroids and meteorites back to the parent bodies that they broke off from in the distant past, as well as understanding the evolution of those parent bodies over time. The findings have been published in the journal Nature Astronomy.

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