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ESA: Small meteorite will safely impact atmosphere tonight over northern France

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Re: ESA: Small meteorite will safely impact atmosphere tonight over northern France

#21
Wow!! From just east of Aachen, perfectly visible. Turning from a point of light coming down into a "oh wow that's really cool" into an actual fireball at >400 km horizontal distance! Holy crap that was exhilarating

Edit: I was expecting that it would be too far away, also with Aachen's city glow and the highway, that nothing would be visible, or at best, a point appearing and disappearing at basically the same location in the haze of city glow. Compared to that, I'm absolutely blown away. Will post a video in a few minutes, just took the 380MB thing off my phone, now cropping to the right ~10 seconds, rotating, that stuff

Edit again: here we are finally https://lgms.nl/files/Sar2667-Aachen.mp4 Quite sad it defocused, and you'll need an x264 decoder in your browser I think (I used `ffmpeg -c:v copy` to avoid losses, so it's whatever encoding my phone uses), should work in a local video player if you download it.

A friend found this one https://www.youtube.com/watch?v=8owpwqzBEPA

Location estimate, based on where I saw it plus this video https://twitter.com/meteordoc/status/1624967987294765059 from Brighton looking over a pier: https://www.openstreetmap.org/?mlat=50.0761&mlon=0.5335#map=...>. It became visible to me at 03:59:13 GMT+1/CET and exploded 5 seconds later, with my phone's clock sync being ~0.6s behind so it might have been 03:59:14

Got so lucky finding that Brighton video as the 2nd result earlier. Spent another 15 minutes looking for a third angle but the "looking east", "looking south" indicated angles are either implausible or too inaccurate to be useful. A Paris video is of such quality that I couldn't for the life of me find out which buildings are in view to map it to an angle. This location guess is going to be my final estimate.

Re: ESA: Small meteorite will safely impact atmosphere tonight over northern France

#25

Impactor is ~1m in size, and projected impact time is 04:00 +/- 10 minutes CET (03:00 UCT). That's about three hours from now as I write this. My very off-the-cuff estimate is that a 1m impactor might mass anything from a few hundred kilos to a few tonnes, depending on composition (less for ice / chondrites, more for a heavy nickel-iron meteorite). Looking forward to the skycam views.

Stupid question: if the impact time is +/- 10 minutes, doesn't that translate into a lot of uncertainty for where it will hit? How do they know it's going to be Rouen?

Think of a bell curve, more or less. It's much, much, much more likely for the asteroid to come down near the center of the predicted range than some place 5 standard deviations away.

Re: ESA: Small meteorite will safely impact atmosphere tonight over northern France

#26
post #13

Earlier quoted context omitted.

Ignoring the sarcasm marker. F15s could fire anti satelite missiles in early 1980s. Who knows what "toys" are available 40 years later. https://en.m.wikipedia.org/wiki/ASM-135_ASAT

But this isnt an orbiting satellite, it's an object moving at 20 km/s (quoting another post, I dont really know in what direction or relative to what) which is ~Mach 60. I don't know how that compares to satellites - is it close enough we'd expect an anti-satellite missile to work?

Depends on what kind of warhead you have on that missile. :)

A small nuke could definitely obliterate a 1-meter rock, if you don't mind contaminating a large part of Europe with radioactive dust.

Re: ESA: Small meteorite will safely impact atmosphere tonight over northern France

#29

Could a F-22 shoot it down? /s

The continuous-rod warhead in a Sidewinder will rip the hell out of an aircraft, which is made of tinfoil wrapped around complications. A rock from space, by contrast, is made out of rock wrapped around rock. Assuming charitably that the missile could generate an intercept, you would probably get some sparks, maybe more or less depending on how much of the rock is actually nickel and iron. But basically, the rock is…

This site truly is where humor goes to die.

Re: ESA: Small meteorite will safely impact atmosphere tonight over northern France

#30

Earlier quoted context omitted.

The continuous-rod warhead in a Sidewinder will rip the hell out of an aircraft, which is made of tinfoil wrapped around complications. A rock from space, by contrast, is made out of rock wrapped around rock. Assuming charitably that the missile could generate an intercept, you would probably get some sparks, maybe more or less depending on how much of the rock is actually nickel and iron. But basically, the rock is…

This site truly is where humor goes to die.

I didn't think I was keeping that straight a face. But on the other hand, now I get to check "twit Cegłowski" off my bucket list, and that's worth a joke falling a little bit flat.
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