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Norwegian skydiver nearly struck by meteorite
- 3327 13y agoHe almost got taken out by 1/100bn odds.
- netcan 13y agoWe all do.
- jon_black 13y agoIs it me or does it look like the "meteorite" is moving quite slow. Shouldn't it be moving so fast that you'd need a high speed camera to see it in that detail? Also...his parachute is always above him, maybe it fell out of that.
- cjensen 13y agoYep; so slow that there is no motion blur. Odds of a meteor are absurdly really low. Much more likely this is a fake or a rock packed in his chute.
- JohnBooty 13y agoMy understanding is that chutes are packed with great care since they're the only thing stopping one from going "splat!" I could believe that it's an intentional fake, maybe, but unintentionally packing a good-sized rock seems unlikely... although, I guess it's not as improbable as a meteor sailing past your head while you're skydiving!
- yan 13y agoIt's probably not a fake or packed inside the chute, since he was under canopy for some time when this occurred. Low odds are not zero odds, but then again, it can be a clever April fools segment. Also, chutes are not packed with great care. A main (the parachute you generally use) takes an experienced packer 5-10 minutes to fully pack and some people hurry through it to get on the next load. Outside of two things you need to get right (make sure the slider is up, make sure lines aren't over the fabric), it will open. Most of the packing is all about reducing the pack volume and slowing down the opening, not ensuring it. A reserve however (the second chute sport jumpers wear), gets packed by a certified packer and gets re-inspected and repacked at least once every 180 days.
- bradleysmith 13y agoVideo was shot on 17 June 2012 according to video at 0:44, so strange april fools timing.
- MrScruff 13y agoMotion blur is a function of distance travelled in screen space per frame and shutter duration, which can be very short for go pro type cameras in bright sunlight. So I wouldn't necessarily expect obvious motion blur.
- wreegab 13y ago> Odds of a meteor are absurdly really low Odds that I win the lottery this week are absurdly low. Odds that someone will win the lottery this week are quite high.
- a3n 13y agoOnce the friction of the atmosphere has had a chance to slow it down, what then is the terminal velocity of a rock that size? Not fast is my intuition. As for falling out of the parachute, and whether it really is a meteorite, the article discusses that: probably not, and almost certainly yes.
- binarymax 13y agoIt had already entered the atmosphere, and probably slowed down significantly due to friction, then based on its mass it reached a low terminal velocity. https://en.wikipedia.org/wiki/Terminal_velocity https://en.wikipedia.org/wiki/Terminal_velocity
- stouset 13y agoRam pressure, not friction
- xenophonf 13y agoTo get really technical, it's wave drag. ;) There's a fascinating discussion here: http://cosmoquest.org/forum/showthread.php?35327-meteors-ram-pressure-vs-friction-vs-impact-ionization http://cosmoquest.org/forum/showthread.php?35327-meteors-ram...
- deleted 13y ago[deleted]
- danbruc 13y agoThe article states that the meteorite already slowed down to around 300 km/h because the incident happened at a low altitude and the heavy braking was already over.
- JshWright 13y agoThat seems about right... It looks like it travels roughly a meter or so between frames, and the GoPro was likely recording at 60fps, so it was traveling somewhere around 60m/s relative to the parachutist. So add another 10 m/s for rate of descent of the camera and you come up with 252 km/h.
- angusb 13y agoI just spent a while looking up the maths on this and was really surprised to find that the terminal velocity of a spherical rock (diameter 10cm, density 2.5g/cm^3) at this altitude is remarkably close to 300 km/h (I got 340). Aside: up until now I had imagined that if a skydiver were to ever drop a rock of that size (or a dense piece of equipment like a DSLR) during freefall they would never be able to catch it, but as the terminal velocity of a skydiver in "dart" position is about 320km/h that's not the case. Pretty cool.
- kzrdude 13y agoIt's right after his parachute opens, so he hasn't slowed down that much yet.
- simias 13y agoYeah, Occam's razor tells me that it's much more likely that a stone got stuck somewhere in their skydiving apparatus than having a meteorite fly right past you while you're skydiving. Maybe I'm underestimating the quantity of meteorites falling on the earth but since the newspapers aren't exactly filled with news of people getting killed by falling rocks I'm not yet ready to believe that was a meteorite.
- ThomPete 13y agoI am not sure how you are using Occams razor there. It's well known that metorites falls to earth. Also see top comment right now.
- nicksergeant 13y agoHe explains in the video why it's not possible to have been from the aircraft or other flyers.
- jmulho 13y agoThe first guy's chute was open. The rock flew past the first guy. Then a second guy (with his chute not yet open) flew past the first guy. When the rock flew past the first guy, the second guy was above him, and whatever aircraft the second guy jumped from must have also been above him.
- jessedhillon 13y agoIf you look at how a parachute is packed, and how it unfolds when deployed, what you described is definitely not the simpler explanation preferred by Occam's razor.
- simias 13y agoWell, since it seems I'm in a minority here I'll accept that I might be misjudging the odds on this one, especially since I know nothing about skydiving. I guess it goes to prove that since nowadays we're almost all carrying video recorders with us at all times the probability of catching the most elusive events on video gets increasingly large. I expect to see a video of someone standing at the foot of a rainbow any day now.
- dimman 13y agoNo it did not fell out of the parachute. To the obvious: If it would have been in the parachute, it would be moving at the same velocity as both the parachute and the man. It obviously can't have been under the parachute, it would have droppped instantly, it doesn't. If it would have been on top of the parachute it would have gotten a push upwards to reduce speed (but its still moving _downwards_ unless some magic explosion happened). Now according to the video, from the time the parachute opens, it takes roughly 8 seconds (!) until the rock passes. During that time the mans velocity decreased substantially due to the parachute... Well just do the math.
- amirmc 13y agoYou can skip to the photo collage to get a better look at it. http://www.youtube.com/watch?feature=player_detailpage&v=jfEdEIwhj6s#t=153 http://www.youtube.com/watch?feature=player_detailpage&v=jfE...
- binarymax 13y agoI did some quick googling and found this interesting research from Oberlin, with a history of meteorite injuries and deaths: 1420 BC Israel - Fatal meteorite impact. 588 AD China - 10 deaths; siege towers destroyed. 1321-68 China - People & animals killed; homes ruined. 1369 Ho-t'ao China - Soldier injured; fire. 02/03/1490 Shansi, China - 10,000 deaths. 09/14/1511 Cremona, Italy - Monk, birds, & sheep killed. 1633-64 Milono, Italy - Monk killed. 1639 China - Tens of deaths; 10 homes destroyed. 1647-54 Indian Ocean - 2 sailors killed aboard a ship. 07/24/1790 France - Farmer killed; home destroyed; cattle killed. 01/16/1825 Oriang, India - Man killed; woman injured. 02/27/1827 Mhow, India - Man injured. 12/11/1836 Macao, Brazil - Oxen killed; homes damaged. 07/14/1847 Braunau, Bohemia - Home struck by 371 lb meteorite. 01/23/1870 Nedagolla, India - Man stunned by meteorite. 06/30/1874 Ming Tung li, China - Cottage crushed, child killed. 01/14/1879 Newtown, Indiana, USA - Man killed in bed. 01/31/1879 Dun-Lepoelier, France - Farmer killed by meteorite. 11/19/1881 Grossliebenthal, Russia - Man injured. 03/11/1897 West Virginia, USA - Walls pierced, horse killed, man injured. 09/05/1907 Weng-li, China - Whole family crushed to death. 06/30/1908 Tunguska, Siberia - Fire, 2 people killed. (referenced throughout paper) 04/28/1927 Aba, Japan - Girl injured by meteorite. 12/08/1929 Zvezvan, Yugoslavia - Meteorite hit bridal party, 1 killed. 05/16/1946 Santa Ana, Mexico - Houses destroyed, 28 injured. 11/30/1946 Colford, UK - Telephones knocked out, boy injured. 11/28/1954 Sylacauga, Alabama, USA - 4 kg meteorite struck home, lady injured. 08/14/1992 Mbole, Uganda - 48 stones fell, roofs damaged, boy injured. http://www.oberlin.edu/faculty/bsimonso/group9.htm http://www.oberlin.edu/faculty/bsimonso/group9.htm
- raimondious 13y agoHey, I took that class in 2004!
- icambron 13y agoI grew up in Oberlin and was friends with Bruce's kids, so this is cool to see in this context.
- bennyg 13y ago
- lotsofcows 13y agoApril Fool?
- lotsofcows 13y agoPresumably the downvote means, "No, but I'm not going to tell you why"? Any Nordic types following this story?
- erokar 13y agoNot April fools'. The story was published by NRK today, 3. of April.
- marvin 13y agoThis was published by NRK, the Norwegian equivalent of BBC on April 3rd, and the guys in the video seem sincere. I suppose it could convievably be an elaborate April fools prank by the skydivers if they talked to NRK on the 1st, I suppose. But I suppose they would have come clean by now.
- dang 13y agoComments that are (a) really short and (b) not obviously substantive almost always get downvoted. If instead you had written: "Could this be an April Fool?", people would have probably have recognized it as a sincere question. Please don't add comments about getting downvoted, though. As the guidelines say, it makes for boring reading.
- CalRobert 13y agoGo to 2:12 if you want to skip the fluff.
- sgt 13y agoThe fluff is actually worth watching as well. The guy is clearly taken back by this experience.
- aDevilInMe 13y agoJFYI To be hit by a meteorite you would either need to be close to the Earth's surface or for somebody strong to throw it. Technically it is not a meteorite until it impacts with the Earth's surface, therefore this object may actually be a meteoroid.
- Crito 13y agoAh, technically correct.. the best sort of correct. It seems to me though that a meteoroid that has evidently survived reentry but has not yet reached "the surface" properly might be something of a previously unhandled edge case. Normally you would avoid naming meteoroids to be meteorites until after you have found them safely on the ground because it is possible that they burned up during their observation, but this one was observed well after the point where it may have burned up. Also from a delta-v perspective, it had already performed the majority of its transition (from kilometers per second to likely less than a hundred meters per second).
- lutusp 13y ago> Technically it is not a meteorite until it impacts with the Earth's surface, therefore this object may actually be a meteoroid. Not quite. Before entering Earth's atmosphere, it's a meteoroid. While passing through the atmosphere, it's a meteor. After landing, it's a meteorite. http://www.livescience.com/27183-asteroid-meteorite-meteor-meteoroid.html http://www.livescience.com/27183-asteroid-meteorite-meteor-m...
- escapologybb 13y ago> While passing through the atmosphere, it's a meteor. Just to be an absurdly pedantic, it's actually only the flash of light that is the meteor and not the rock itself. http://hubblesite.org/reference_desk/faq/answer.php.id=22&cat=solarsystem http://hubblesite.org/reference_desk/faq/answer.php.id=22&ca...
- aDevilInMe 13y agoMeteor is a description of the burning in the atmosphere not the object itself, which is still a meteoroid.
- d_theorist 13y agoIsn't it more likely that the rock fell out of their plane?
- protek 13y agoHe says at 1:20 that the plane is below them the entire time. That was my initial thoughts too, though.
- JshWright 13y agoThe plane is well below the skydiver (about to land) when the rock passes by. There's no way it came from the plane.
- dredmorbius 13y agoHe addresses that in the video: other jumpers and the plane are not above him at this point, so odds are the rock came from elsewhere. The presumes a reliable narrator, but it seems plausible. This is one guy with an in-flight asteroid sighting. Not as if they're crawling out of the woodwork. And the experts called in seem to find this credible. Though people hamming up an act for cameras is also not unheard of.
- base698 13y agoGiven its a wingsuit jump he's likely miles from where they exited the plane. The rock would have a more straight down trajectory as well. You can tell the forward speed when the other jumper comes by.
- hdevalence 13y agoI wonder if it's possible to use computer vision techniques on the video footage to calculate the position and altitude of the skydiver at the time, and then also estimate the trajectory of the rock?
- chillax 13y agoSome analysis going on here at least (text in norwegian though): http://norskmeteornettverk.no/wordpress/?p=1329 http://norskmeteornettverk.no/wordpress/?p=1329
- ForHackernews 13y agoThey keep talking about how lucky he is it missed him, but I almost think the opposite is true: He'd have to have been staggeringly unlucky to have been hit by it.
- FatalLogic 13y agoIn fact, he was doubly lucky. Firstly, he was incredibly lucky to have witnessed a meteorite passing a few meters from him. Secondly, he was very lucky not to be killed by the meteorite that was passing a few meters from him.
- gandalfu 13y agoTriple lucky for capturing those events in video!
- tummybug 13y agoSeems strange that the other diver is following the same path as the meteorite and passes by just a few seconds later. Could he have dropped it and it accelerated to a speed faster than he was travelling?
- ynniv 13y agoie, thrown it? That does seem far more likely than it being from space.
- CodeCube 13y agoIf he threw a rock of that size at his buddy ... what a jerk
- cratermoon 13y agoPeople are stupid, sometimes. Especially on internet videos.
- peterwwillis 13y agoPossibly. A small rock would have a lot less air resistance than a person, and those suits are designed to increase air resistance. So it might end up with a higher terminal velocity and fall slightly faster. http://www.wired.com/2013/10/do-heavier-objects-really-fall-faster/ http://www.wired.com/2013/10/do-heavier-objects-really-fall-... http://www.physicsclassroom.com/mmedia/newtlaws/efar.cfm http://www.physicsclassroom.com/mmedia/newtlaws/efar.cfm
- lutusp 13y ago> A small rock would have a lot less air resistance than a person, and those suits are designed to increase air resistance. So it might end up with a higher terminal velocity and fall slightly faster. This is a bit more complicated than it appears at first glance. Other things being equal, a 3D object's mass increases as the cube of a single dimension's increase, but its surface area increases only as the square. Therefore a smaller object's atmospheric terminal velocity can be expected to less than that for a large one. This is why many kinds of small animals can fall great distances through the atmosphere and land unharmed. (Until objects approach terminal velocity, they all fall with the same profile. Only when approaching terminal velocity do their speeds change.) On the other hand, a typical rock (non-metallic) has 3.5 times the density of a human, so that argues in favor of a greater terminal velocity. A full analysis would need to take into account the human's flight suit, which turns vertical kinetic energy into horizontal kinetic energy, and the rock's size, shape and composition. But without any of this and a priori, the idea of a rock flying past a human, as in the video, is perfectly reasonable. One more thing. The picture of the rock passing by the human is actually most likely a person flying horizontally past a rock that's dropping vertically.
- dredmorbius 13y agoA related question: what's the probability of an aircraft being struck by a meteor. Seems this question was asked in the wake of the Air France flight 447 disappearance (since resolved as pitot tube freezing combined with pilot error and control feedback failures of the Airbus design). But still, the odds of a strike on _an_ aircraft over the next 20 years are about 4%: http://blog.revolutionanalytics.com/2009/06/how-much-of-a-threat-are-meteors-to-aviation.html http://blog.revolutionanalytics.com/2009/06/how-much-of-a-th... at any given time, airliners cover 2 billionths of the Earth's surface. There are 125 meteors an hour, each with probability 2x10-9 of striking some airplane. In 20 years, that's about 22 million independent possible impact events. The chance that every one of those meteors misses every airplane is: ppois(0,2e-922e6)* (Using R). So the odds of an asteroid flying past a skydiver aren't as infinitesimal as one might otherwise think. It also makes one wonder at the possibility of space-junk collisions being the cause of past aviation accidents. There's little enough evidence this would leave, particularly for a flight which disappeared entirely without a trace, or whose wreckage was only found much later.
- bitL 13y agoThat would be under an assumption that the distribution of planes around the globe is even. Given most jetliners are flying in corridors, I would say the actual probability is much much lower. The same can be probably said about meteorites - I guess their geographic distribution is uneven as well.
- surrealize 13y agoIf the meteorite strikes are evenly distributed, and if the planes aren't actually stacked (i.e., flying directly above one another) very much, then I don't think the plane positions matter for this calculation.
- rz2k 13y agoIf the distribution of meteors is perfectly even and all of the planes are parked next to each other in the desert, then the probability should be the same 4% expectation within the next 20 years of one of those parked aircraft being hit. While staying within corridors would not matter, the distribution by latitude probably does, and my guess is that they align enough to actually increase the odds.
- dclowd9901 13y agoI'm... skeptical. If you look at the frames of the meteorite falling, it looks like each frame has the fragment at about 3 feet from its last position. If that's a 60fps camera (I think it is?), that's 180 f/s speed or 122mph. That seems really slow for a rock flying into the atmosphere from space, and far slower than a rock would have to be going for it to "cut him in half." My guess: a rock that fell off the undercarriage panel of an airliner, and was carried by strong winds. Or a particularly slow meteorite.
- ProAm 13y agoThese rocks slow down considerably when they move through the atmosphere (Unless they are massive and this one was not). What is also interesting is most the time they are cold to the touch immediately after impact.[1][2] [1]http://misconceptions.us/are-meteorites-hot-or-cold-when-they-hit-the-earth/ http://misconceptions.us/are-meteorites-hot-or-cold-when-the... [2] http://curious.astro.cornell.edu/question.php?number=215 http://curious.astro.cornell.edu/question.php?number=215
- Zigurd 13y agoGoPros have high frame-rate modes.
- allthatisgold 13y agoCamera isn't stationary.
- dclowd9901 13y agoEven if it's not, the relative speed is what's the issue here. The thing I take most issue with is his statement that this rock would've killed him. If it's only moving 120 or so mph in relation to his speed, it probably wouldn't kill him, let alone cut him in two.
- jameshart 13y agoLet's say that meteorite is about the size of a baseball. 120mph is faster than a fastball baseball pitch, and getting hit by a fastball? That can do damage, which is why baseball players wear protective gear (the catcher's padding is not for show). An iron nickel meteorite is maybe five-six times denser than water; a baseball? Well baseballs float - they're about 2/3 as dense as water. So the meteorite is maybe 3-4 times as dense as a baseball, going 20% faster than the fastest fastball ever recorded; so it's carrying more than 4 times the kinetic energy of a fastball. If that hit you, it could certainly be immediately fatal, or at least cause severe injuries; I would imagine that becoming severely injured while skydiving comes with a significantly increased risk of death. But maybe he's just being a drama queen.
- uptown 13y agoCould it have fallen from some other plane, they weren't aware of, that was above their altitude or do the principles of terminal velocity and gravity not support that hypothesis?
- woodchuck64 13y agoShouldn't we be expecting a rock that has just been heated to plasma stage by atmospheric friction only seconds earlier to be glowing, steaming or leaving little molten fragments of itself behind? Update: maybe not. The last stage of flight is "dark and cold" according to this: http://www.meteorite-recon.com/en/Meteorite_fusion_crust_1.htm http://www.meteorite-recon.com/en/Meteorite_fusion_crust_1.h...
- deleted 13y ago[deleted]
- jessriedel 13y agoI imagine the rushing air can cool a rock pretty rapidly. The increase in terminal velocity will also tend to partially counteract the increased volume:surface-area ratio of larger rocks.
- jccooper 13y agoIt has to be a pretty big rock to be hot when it hits the ground. Smaller pieces, on landing, are often found to be quite cold, entry heating not being long enough to remove the in-space cold soak, and the upper atmosphere being chilly.
- goodcanadian 13y agoAs I understand it, the rock doesn't get especially hot. The hot surface ablates, and the rock underneath remains relatively cool (doesn't have time to heat up). From http://en.wikipedia.org/wiki/Atmospheric_reentry#Blunt_body_entry_vehicles http://en.wikipedia.org/wiki/Atmospheric_reentry#Blunt_body_... (admittedly about spacecraft rather than meteorites): "Through making the reentry vehicle blunt, air cannot 'get out of the way' quickly enough, and acts as an air cushion to push the shock wave and heated shock layer forward (away from the vehicle). Since most of the hot gases are no longer in direct contact with the vehicle, the heat energy would stay in the shocked gas and simply move around the vehicle to later dissipate into the atmosphere."
- InclinedPlane 13y agoSmall rocks will experience substantial heating around their outside and will form a melt crust, but this cools down very quickly once the rock has slowed down. Most small meteorites are still cold in their interiors when they land.
- nly 13y agoI don't know why everyone is assuming it was so close. It looked further away from the dude to me... i'd guess ~100 feet or more. In any case, given camera optics, you can only solve for size or distance given the other.
- FatalLogic 13y agoThis site has more information. It's in Norwegian, but there are some charts and graphics which give an idea how they've been trying to locate the rock by analyzing the video and checking wind speed records. http://norskmeteornettverk.no/wordpress/?p=1329 http://norskmeteornettverk.no/wordpress/?p=1329 They estimate the speed of the falling rock at 280km/h (vertical) and the speed of the guy in the wingsuit at 148km/h (at 37 degr). It seems like they're still uncertain about the exact speed, though. The wind speed was about 5m/s. One document in the video suggests the altitude that the rock passed him was 1200m... so the rock would have hit the ground 15 seconds later at 280km/h The research website mentioned in the article is linked on that page, but it isn't up yet.
- BigTuna 13y agoIt's extremely hard to discern but it looks like there was possibly another smaller piece that goes flying by just before the camera stabilizes and the main meteor comes into view.
- jccooper 13y agoThat would make sense; it's clearly a fragment from a larger object that broke up during entry, probably late in the heating phase. (There is a visible dark "outside" and light "inside" on the piece we see.) So there are likely to be other pieces nearby.
- olt 13y agoCould it be Blue Ice[0] or a similar leakage from an airplane flying above the skydivers? [0] http://en.wikipedia.org/wiki/Blue_ice_(precipitation) http://en.wikipedia.org/wiki/Blue_ice_(precipitation)