Record Meteorite Hits Norway

equex256 writes "Early Wednesday morning, a meteorite streaked across the sky in northern Norway, near Finland and Russia. A witness (Article in Norwegian) went up the mountain to where it hit and reported seeing large boulders that had fallen out of the mountainside, along with many broken trees. Norwegian astronomer Knut Jørgen Røed Ødegaard told Aftenposten, Norway's largest newspaper, that he would compare the explosive force of the impact with the Hiroshima bomb. This meteorite is suspected to be much larger than the 90-kilo (198-pound) meteorite which hit Alta in 1904, previously recognized as the largest to hit Norway. From the article: 'Røed Ødegaard said the meteorite was visible to an area of several hundred kilometers despite the brightness of the midnight sunlit summer sky. The meteorite hit a mountainside in Reisadalen in North Troms.'"

Comments

Lucifer's tack hammer.

[Ungrounded Lightning]

(See Niven and Pournelle for consequences of a larger one.)

Giant Røck

[Anonymous Coward]

Do meteørites sound different with a slash through the middle?

Re:Giant Røck

[Man Eating Duck]

I'm Norwegian.

The vowel ø in Norwegian is pronounced like the vowel sound in "sun".

Have føn :)

BTW, the astronomer mentioned (Knut Jørgen Røed Ødegaard, try it :) is something of an astronomer celebrity here. The press will always go to him when there are spectacular events, like this, or eclipses. He's done a great job to make astronomy accessible and fun to less technically inclined people, both by giving public lectures on fascinating subjects, and by writing a couple of books on "popularized astronomy".

Cheers

Obligatory Meteor Video

[Anonymous Coward]

Yeah its probably fake, but cool nonetheless:
http://video.google.com/videoplay?docid=4653448813 733199771&q=meteor

And for all you language nazis out there, meteorite is a silly word and should be abolished.

Re:Obligatory Meteor Video

[ACDChook]

And for all you language nazis out there, meteorite is a silly word and should be abolished.

I think you'll find that by definition, an object is a meteor while it falls through the atmosphere, and the rock that hits the ground is a meteorite. If it burns up in the atmosphere, then there is no meteorite, just a short-lived meteor.

Re:Obligatory Meteor Video

[morcego]

Actually, you are right:

Metoroid -> Atmosphere -> Meteor -> Ground -> Meteorite

Hiroshima?

[Durrok]

I guess but if I recall correctly hiroshima did a little bit more then just "blow in some curtains". Even if accurate this is a pretty bad metaphor, the Hiroshima bomb brings on ideas of destruction and chaos. Even if you took the radiation aspect away from the Hiroshima bomb it still would have done far more damage. Guess the whole line of "location, location, location" really is true.

Re:Hiroshima?

[iamlucky13]

Of course the meteor would not have had any noteworthy radioactivity and was not in a populated area. I don't remember exactly how often it's estimated to happen and I can't find any sources, but meteors of this size hit the earth a lot more often than most people realize...something like between once a year and once a decade. The comparison to Hiroshima really is about the energy of the impact, not the destructiveness. Little boy had a yield equivalent to approximately 15,000 tons of TNT.

Re:Hiroshima?

[Silverlancer]

The curtains were something like 150km away from the meteor impact... I expect Hiroshima would have done similar at that range.

Re:Hiroshima?

[Nutria]

I guess but if I recall correctly hiroshima did a little bit more then just "blow in some curtains".

If Little Boy was detonated in the far northern mountains of Norway, it also would have had similar minimal effect.

Re:Hiroshima?

[NewmanBlur]

I've been to Hiroshima. The atomic bomb killed 140,000 people, if you include those who died of bomb-related injuries and illnesses, within (iirc) a year after the attack. If you increase that to five years, the number increases by many thousands, though I don't recall the exact number.

The bomb levelled literally the entire city -- only one building remained, now referred to as the Genbaku Dome . It's still standing, but it has been re-inforced with a steel structure to retain the shape it was in after the war.

Anyway, the point is that even if this meteor was "substantially bigger" than the 200-pound record holder, I find it extremely hard to believe that it would do even a miniscule fraction of the what the A-bomb did.

Re:Hiroshima?

[Anonymous Coward]

If Little Boy was detonated in the far northern mountains of Norway, it also would have had similar minimal effect.

I don't know. I think that might have had a significant effect on American-Norwegian relations, even if Norway was Nazi-occupied at the time. :)

Hmmm...

[th1ckasabr1ck]

Was it as big as the one that (supposedly) fell at Tunguska? Although I'm still pretty sure that was caused by dark matter or a UFO or something.

Yeah, but...

[tool462]

he would compare the explosive force of the impact with the Hiroshima bomb.

Yeah, but how many Libraries of Congress is that?

Meanwhile in Cupertino...

[daeley]

Steve Jobs's giant wallscreen sparkles to life. A visibly pale and shaken Prime Minister Jens Stoltenberg appears with a panicked situation room full of Norwegian officials behind him.

"Ah, Prime Minister, good," Jobs says with a trademarked smile. "I see you got our little message. Let's finish our chat about DRM regulations...."

(reference)

A Meteørite ønce hit my sister

[EGSonikku]

Nø really! She was carving her initials intø the side øf a røck with a sharpened interspace tøøthbrush given tø her by Svenge -her brøther in law- an an øslø dentist and star øf many Nørweigan møvies: "The Høt Hands øf an øslø Dentist", "Fillings øf Passiøn", "The Huge Mølars øf Hørst Nørdfink"...

Mynd you, Meteørite hits kan be pretti nasti .....

Oblig. Impact Calculator

[Anonymous Coward]

Whenever the topic of meteors comes up, someone has to post a link to the University of Arizona impact effects calculator. Play with the numbers, see if you can destroy the earth.

Also worth checking out along the Lucifer's hammer line of thought is How to Destroy the Earth

I tried a quick reverse engineering of the meteor with the calculator. An iron meteor 4.5 meters in diameter moving 20 km/s hitting crystalline rock at 45 degrees will have a yield of 18 kilotons...slightly higher than the atomic bomb detonated over Hiroshima. The average interval of an impact of this size on earth is about once every 5 years. Most go largely unnoticed. The earth is a big place.

Re:Is this real?

[49152]

Yes, it's real. The impact also showed up on seismic recorders http://www.astro.uio.no/ita/nyheter/ildkule06/ildk ule06.html (You can study the images in this Norwegian article from the University of Oslo).

paging Google Earth...

[TheSHAD0W]

I wonder (1) how recent and what resolution Google Earth's latest imagery is, and (2) can we get them to take another shot ASAP and compare them?

It's how you distribute the energy.

[DigiShaman]

There is a difference in how the energy was distributed. With the A-Bomb, it was an atmospheric blast. With the space rock, the energy was absorbed into the Earths crust.

Re:It's how you distribute the energy.

[Deadstick]

Should be modded up. An airburst sends down a mongo shock wave that flattens structures over a big area (not to mention the radiation that isn't a factor in the case of a meteor impact). A ground impact/explosion "over-destroys" a much smaller area, using its energy to excavate a crater instead of knocking buildings down.

The Tunguska event of 1908 devastated a really big area because it was an airburst: apparently a comet whose ice content flashed into steam when it hit the atmosphere.

rj

Re:Hmmm...

[LaminatorX]

Actually, I saw a paper presented back in the late 90's that fairly convincingly made the case for a mostly iron meteor. The author's contention was that the object slowed due to air resistance, it would heat up. As is heated, the metal would have softenned. As it softenned, the metal would start to pancake like a dum-dum bullet. As it pancakes, its air resistance increases, causing it to slow down even more and heat up even faster, causing it to pancake even more... until you get an airbirst at an altitude with on the order of magnitude suggested by the tree angles at Tunguska. If you acept his hypothesis about the meteor's composition, there were no major contradictions in the evidence.

Re:The Hit

[Ironsides]

Im just happy that it didnt hit anywhere else. Like New York, or any other big city.

I almost (alomst!) wish it landed near enough one to cause some decent damage. Then maybe people would take the threat of a planet killer serious enough to get a properly funded space program going so a some of us could get off planet (like me). AD ASTRA!

Wish they made it easier to do rev. calcs

[jd]

I reversed the calculation to guess at how big the rock was that created the crater in Antarctica that was recently discovered, which is 300 miles across. I assumed that the asteroid had a fairly low density (porus rock). Assuming the object is travelling "slowly" (11 km/s), it would need to be 60 miles across to create a final crater of the necessary size. Even at 300 miles away (the edge of the crater), wind speeds would hit 8200 mph and the earth tremors would still be 11.3 on the Richter scale. A "typical" asteroid strike would be 17 km/s. To create the necessary crater, you'd be looking at a lump of rock 45 miles across. Most of the effects would be the same, except there would be a gigantic fireball. Again, at the crater's rim, you'd be looking at 8.53 x 10^10 joules/m^2 of energy for about 9110 seconds - enough to vaporize anything remotely close to the impact.

Assuming typical velocity, an iron asteroid would be a mere 22 miles across. The radiation would only be two-thirds that of the porus asteroid at the same speed.

If this was indeed the impact crater that triggered the initial phase of the Great Extinction, then the low density/high energy strike would produce vastly more heat and therefore affect the climate that much more.

Re:Now for the science!

[RsG]

Perhaps you're mistaking entry mass for landing mass?

A meteorite's surface vapourizes from reentry heat when it enters the atmosphere. If the meteorite is small enough, the entire object will be plasma long before it hits the ground; it takes a large or dense object to survive reentry, and even then much of it's mass is lost.

That doesn't however mean that it disperses. There is at least one theory that a meteorite could hit the ground as a ball of plasma with a solid core, due to the surrounding air pressure preventing the superheated surface from dispersing even after it vapourizes. I seem to recall seeing this put forward for the Tunguska blast in Siberia. IANA Astrophysicist, so I don't know how fast the object would need to be moving, or how large it would have to be initially, to produce this effect.

If that did happen, what would you use for your calculations? The mass of the meteorite wouldn't all be solid when it hit, and whatever material wasn't vapourized by descent or on impact would only make up a fraction of the mass present during the impact. The core might be 90kg, or 300kg, or whatever, but using that figure to calculated the speed the object on impact would be incorrect. You'd need to mass of the meteorite on reentry, minus whatever mass bled off during descent.

However, I would agree that comparing the impact to an atomic bomb blast is silly. It's like comparing a firecracker explosion to a bullet impact - yes, you can say that one has X amount of energy and the other has Y (and you could probably calculate this by measuring the gunpowder present in each, and determining how much energy you get from burning it), but that comparison doesn't actually tell you anything useful, since the energy is applied in a very different fashion. It's comparing apples to oranges.

Re:8.5 x 10^-2 bLoC

[Farmer Tim]

Meteor sizes are measured in the "Texa".

Damn it, when are you Americans going to start using internationally recognised units?!?