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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

#61

Post by dEnigma »

Aachen wrote: post #49
caporaltito wrote: post #48

Earlier quoted context omitted.

> Holy crap that was exhilarating A perfect occasion to... laachen?

> exhilarating - causing strong feelings of happy excitement and elation TIL that refers specifically to feelings that would cause laughing. Took me a while to get your pun, also because (to this dutchman) aachen is two sounds removed from lachen and not one like it might be for a german (where they hardly differentiate between short a and long aa). I find it hard to describe feelings (in any language), maybe "shocki…

"Aufregend" sounds fitting to me as a native German speaker. In most contexts I would translate it as "exciting". It can have some more negative connotations, in the "getting worked up" sense, but mostly when used like "sich über etwas aufregen" (so as a verb not an adjective), and when describing your feelings regarding this event it's more on the "exciting/thrilling" side.

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

#62

Post by rvba »

kijin wrote: post #26
version_five wrote: post #16

Earlier quoted context omitted.

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.

Some sort of a bunker buster perhaps? ( https://en.m.wikipedia.org/wiki/Bunker_buster ) Or a tungusten rod with no warhead at all.

Not sure if they arent much bigger than an anti sat missile though.

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

#63

Post by timthorn »

Aachen wrote: post #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 locat…

UKMON has received 40 reports and 4 videos so far, from which they have the meteor coming into Dieppe http://ukmon.imo.net/members/imo_view/event/2023/937

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

#65

Post by roenxi »

rvba wrote: post #60
throwanem wrote: post #20

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…

There are bunker busters but most of them are conventional bombs, or cruise missiles (with a propeller). If they can bust few (double digit?) meters of concrete, they could bust a rock. Assuming they dont miss and assuming they dont slip. https://en.m.wikipedia.org/wiki/Bunker_buster Obviously it would have to be some combination of an anti sat missile (so it can fly in space) and a bunker buster (so it can crush thr…

My physics is a bit rusty. Would that help? There is a rock with huge amounts of kinetic energy and you hit it with a bunker buster, then what? You've then got the same amount of mass (mass being conserved) and the same amount of energy (energy being conserved) on more or less the same trajectory.

I'm not sure that counts as shooting it down. In the context of a celestial object usually "shoot it down" means "deflect it so it misses earth".

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

#66

Post by tehc-uk »

Aachen wrote: post #41
tehc-uk wrote: post #33

I happened to be up watching the Super Bowl in the UK, saw the ESA tweet across my timeline and was able to pop outside to see it at the time they predicted - was also able to grab a video [0]. So cool to see how far our detection of these objects is coming along, especially for something as small as this was. [0] https://twitter.com/teh_c/status/1624967399131824130

Would you be willing to share your exact location, perhaps in an email to sar2667observation@lgms.nl? From a sibling comment: > 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…

https://snipboard.io/4T8Qvf.jpg

Does this help at all? The line on the left is when the object first becomes visible in the video, and the line on the right is when it explodes and disappears from view - it's actually pretty similar to what you had already.

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

#67

Post by throwaway4aday »

Aachen wrote: post #51
spenczar5 wrote: post #39

Earlier quoted context omitted.

Two related reasons. 1m is quite small, so it needs to be close for us to detect it. Since we don’t have many observations, the error in estimates of its orbital path is high. In general, it also is extra difficult to calculate the exact last little bit of a trajectory that will impact earth because the force models start getting really wild as something gets very close to earth - approximations stop working.

> it also is extra difficult to calculate the exact last little bit of a trajectory that will impact earth because the force models start getting really wild What kind of forces? I assume you're talking about the space part, before atmosphere, so I would assume it's the same gravity effects that you also get in space, just that gravity is a bit larger value. I wrote a gravity simulator at lgms.nl/p/badgravity so I ha…

My guess is that the uncertainty has little to do with gravity, although there is gravitational variation in both the Moon and Earth depending on what part you are close to but I don't think that comes into play here. The error is likely more to do with the observational data. Try pinpointing the exact distance and trajectory of a 1m rock using ground based telescopes. Hard enough but remember there is also atmospheric distortion and you only get limited time on the scope.

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

#68

Post by throwaway4aday »

roenxi wrote: post #65
rvba wrote: post #60

Earlier quoted context omitted.

There are bunker busters but most of them are conventional bombs, or cruise missiles (with a propeller). If they can bust few (double digit?) meters of concrete, they could bust a rock. Assuming they dont miss and assuming they dont slip. https://en.m.wikipedia.org/wiki/Bunker_buster Obviously it would have to be some combination of an anti sat missile (so it can fly in space) and a bunker buster (so it can crush thr…

My physics is a bit rusty. Would that help? There is a rock with huge amounts of kinetic energy and you hit it with a bunker buster, then what? You've then got the same amount of mass (mass being conserved) and the same amount of energy (energy being conserved) on more or less the same trajectory. I'm not sure that counts as shooting it down. In the context of a celestial object usually "shoot it down" means "deflect…

If you break it apart then you have more surface area to interact with the atmosphere.

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

#69

Post by throwaway4aday »

version_five wrote: post #16
rvba wrote: 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?

Does an anti-satellite missile work by catching up to a satellite or by intercepting it head on or at a tangent?

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

#70

Post by johnaspden »

rvba wrote: post #13
GalenErso wrote: post #12

Could a F-22 shoot it down? /s

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

it's an ironic sarcasm marker
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