It’s kind of pathetic there’s so little news about this. I stumbled across it perusing the Space.com site. They say the impact caused an explosion comparable to a small nuclear bomb. Fortunately, the thing hit a mountainside in a remote region of the country, so no one was hurt that I can tell. Kind of wish I’d been around to witness it (from a safe distance, of course). I’m hoping more news, and some photos of the impact site, get published soon.
"This is simply exceptional. I cannot imagine that we have had such a powerful meteorite impact in Norway in modern times. If the meteorite was as large as it seems to have been, we can compare it to the Hiroshima bomb. Of course the meteorite is not radioactive, but in explosive force we may be able to compare it to the (atomic) bomb," Røed Ødegaard said.
If that thing had hit a city…yikes. Wonder how long it would take to cool off enough for study?
Wow that is news !! As others have said, the media has its priorities straight. :rolleyes: As you know, it is much more vital that we know about Brad Pitt, Angelina Jolie and their baby.
I guess this is one “near Earth object” that escaped detection. I would hope something like this would alert people to the need for a much more ambitious program for detecting these objects. This stuff must be important - afetr all, they recently made two movies about such an event.
Not that impressed? Well, according to the brief article, reports of multi-kiloton events may have been quite exaggerated. Initial estimates of the size of the rock may have been off by about an order of magnitude. Still pretty cool, but not as spectacular or unique as originally claimed, it seems likely.
I suppose, upon reflection, that one possibility could account for both the rather wimpy impact crater, and the reports of a large blast: The thing blew up before impact (as space rocks do quite often), and some good-sized chunks survived the explosion to strike a mountain or two. If I recall correctly, kiloton or bigger explosions caused by stony meteorites or comet fragments that don’t survive the intense friction of entry occur not infrequently in the upper atomosphere.
In fairness, I did hear about this impact last week. I don’t remember where I read about it, but it had to have been a mainstream media outlet. They didn’t compare it to an A-bomb though.
An asteroid 5-10 meters in diameter can cause a 10 kiloton explosion. With our current technology, they are undetectable in space. There are hundred of thousands of them in near-earth orbit–and that’s probably a lowball estimate. On average, roughly speaking, one hits the Earth each year. Luckily the Earth has a lot of uninhabited surface such as, say, the oceans and mountainous regions of Norway. Short of a godlike increase in our ability to a) detect asteroids, b) determine their orbits and c) keep track of all the predictions, astronomers will never be able to give any warning that one of these little guys are going to hit.
Well, I think what the guy was trying to say is your typical stony meteorite isn’t hot when it lands, as it stays remarkably cool during reentry, except for a thin crust on its surface, shedding a lot of heat by ablation, and conducting almost none of that heat to its interior. In fact, it’s not the heat that makes them explode during reentry, but the pressure differential from the leading surface of the meteor to the wake. So much air piles up on one side the thing just gets pulverized.
An iron-nickel meteorite conducts heat from its surface a bit better, and may remain pretty hot for a while after landing. I don’t know if those would ever be incandescently hot, though. Probably not. Does anyone know how much, say, uranium a metal-rich meteorite might have in it?
