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merc@sh.itjust.works 3 days ago
225m for a hit where there’s no atmosphere to slow it down. I wonder if something that would cause a that size of crater on the moon would even make it to the Earth’s surface, or if it would burn up before it hit.
westo232@lemmy.world 2 days ago
It depends on the material.
If the same asteroid that created the 225m wide crater on moon hit earth instead it would burn up in earth atmosphere if it was rocky in nature (~3.6m wide, 73 tons).
If the crater was made by a mostly iron asteroid, it would create a 12.5m crater on earth (~2.3m wide, 51 tons).
The reason for this is that rocky asteroids shatter thus have bigger surface area to burn up.
Iron asteroids stay solid and survive the atmosphere much easily.
Multiplexer@discuss.tchncs.de 2 days ago
Just two weeks ago we had a meteor of that estimated size range in my home region (western Germany).
The moving fireball and bright disintigration flashes were visible in a > 100km radius even though it was not completely dark yet.
Areas directly underneath also reported hearing a loud boom.
One of the fraqments caused a soccerball-sized hole in a roof and was recovered from the bedroom underneath.
wewbull@feddit.uk 2 days ago
12.5m?
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merc@sh.itjust.works 2 days ago
A 12.5m crater doesn’t sound that big. Sounds like what you get from a bomb in a war zone. Bad if you happen to be right next to it, but If you’re a few blocks away you might have shattered windows, but no structural damage.
Where did you get the numbers btw? I took a quick look and couldn’t find any details on how big the asteroid was.
westo232@lemmy.world 2 days ago
I agree it’s not big at all. Also there’s a 2/3 chance it goes into the ocean not creating any crater at all.
I just ran some scenarios through AI. I’m not any kind of physicist or anything like that, but I tested some gotchas and the results seem to be reasonable (in a What If kind of way of thinking - the numbers should be correct in order of magnitude).
Only ~8% of asteroids falling on the Earth are metallic.
You can get the size of the original asteroid from the size of crater (mass of the moon and the nature of regolith are known). The biggest variables are speed of the asteroid and angle of impact (I took a reasonable guess and assumed they are not changing in these scenarios). Whether the original asteroid was mettalic or not we may never know.