Re: [meteorite-list] Noblesville IN possible meteorite landing December
Correct. Generally, the strongest indication that something fell really far away is people reporting that it fell at most a few miles away. If something actually falls within a few miles, this is what you would experience: The meteor climbs pretty much exactly vertically after been first seen before it breaks up or fades high in the sky. The terrain will be illuminated before it fades. After 0.5 to 1.5 minutes there would likely be a loud sound followed by rumble. The rumble could start as a strange sound with rapidly falling pitch. Further away there will be just regular rumble. -Steinar Chris Peterson via Meteorite-list writes: > If you saw it break up near the horizon, any meteorites produced are > 100 miles or more away from you. For meteorites to be within a few > miles of your location you would have seen it break up directly > overhead. > > Chris > > *** > Chris L Peterson > Cloudbait Observatory > https://www.cloudbait.com > > On 1/19/2022 6:09 PM, Chris Friedman via Meteorite-list wrote: >> Hello all, >> >> First week of December 2021, I was hanging out in my hot tub when a >> large blue/green trailing sighing that stretched from the left to >> right across the entire horizon and then broke apart into pieces and >> fell to the ground. We spend a lot of time back there staring at the >> skies and I have a good feeling that this landed approximately >> within 2 miles from our home. I’ve never seen anything like this in >> my life. >> >> I feel like me and my family may be the only people that are aware >> of this sighting and I feel like I should share this with the >> group. There was nothing in the local news or social media about the >> sighting. If you are a serious hunter of meteorites and would like >> to reach out to me for more info, send me an email. >> >> Thanks! >> Chris >> >> Sent from my iPhone >> __ >> >> Meteorite-list mailing list >> Meteorite-list@meteoritecentral.com >> https://pairlist2.pair.net/mailman/listinfo/meteorite-list >> > __ > > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > https://pairlist2.pair.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist2.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] hot vs. cold meteorite falls
A meteoroid could possibly travel in the Earth's shadow for several hours before it reaches the atmosphere, and this could be enough to cool down its interior if not a particularily large meteoroid. But a core temperature near 0° C sounds reasonable as a typical value. Earth would be -18° C without an atmosphere, but has a much higher albedo than the typical meteoroid. Obviously, 10 seconds or less of heating in the atmosphere will not change the core temperature much. And a couple of minutes of falling in temperatures well below freezing will cool down the melted crust. In some cases the dark flight can be as low as one minute or so, like the 2020-11-07 iron meteorite that fell in Sweden and it wouldn't surprise me if the meteorite was pretty warm to touch just after impact in that case. Most people view meteorites as fireballs smashing into the ground leaving a flaming crater, so the expectation is usually that they're very hot. I have received many reports of melt holes in icy lakes that people are convinced must have been caused by red-hot meteorites. -Steinar Chris Peterson via Meteorite-list writes: > A meteoroid in space is nominally at or just above freezing (i.e. 0° > C), but there is a fair range around that, especially toward the > higher end, depending on its emissivity. It almost certainly will not > be very cold. Space is not "cold". It is, of course, dominated by > radiative heating and cooling. While it is radiating into something > just barely above absolute zero, it is also absorbing the same amount > of solar energy as a rock on the ground. > > In most cases, I would expect a meteorite to be on the cold side when > it impacts. The heating that occurs during its brief ablative phase > will have almost no effect on its internal temperature. But it will > spend several minutes falling through air at one or two hundred meters > per second, and for almost all of that time the air will be on the > order of -40° C. That will result in significant cooling of typical > meteorites of a few hundred grams to a few kilograms. > > I think that what can easily happen is that people who touch a freshly > fallen meteorite actually experience cold as hot, due to their > expectations. Whether we perceive something as hot or cold can be > unrelated to the actual temperature. Remember that kids' game where > you dare somebody to keep their back to you while you touch the back > of their neck with a hot iron, and then actually touch them with an > ice cube? Most people startle and believe you've burned them. > > Chris __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Ådalen, Sweden: 14 kg iron meteorite found
Probably the main fragment of the 7 Nov fall. https://www.thelocal.se/20210223/meteorite-hunters-find-swedens-first-ever-new-fallen-iron-metoerite I think this is the world's first iron meteorite with known oribital elements. And the sound of the meteorite, the "projectile sound" (falling pitch) sometimes reported can be heard here, recorded only a few km away: https://www.youtube.com/watch?v=XwY1Wib5d5U -- Steinar __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Rocks found from November Sweden event?
Bob Loeffler via Meteorite-list writes: > "It was very lucky that this meteorite hit the rock first," Langhof > explained. "If it hits soft ground, an iron meteorite will be buried four or > five metres down, and you > won't find it afterwards. It's gone." > > Huh? Sounds very fishy to me. If an iron meteorite hits soft ground like peat, that is quite possible. An iron meteorite weighing tens of kg or more probably wont reach terminal velocity, so if it hits soft peat, it will be very hard to find. But in this case it hit a rock, then the forest ground and it should not be buried. Yet, no meteorite was seen. Which leaves a likely explanation: Somebody had already removed it and did not report it. And that is a sad situation, since the material found is not sufficient for proper classification. And the finder has a lump of iron of limited value. If properly confirmed as an iron meteorite, I think it will be the first iron meteorite with known orbit. -- Steinar __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Northern Taurid as bright as the full Moon
Hi We just set up new cameras in Skibotn, Norway and calibrated them last night. Today at 14:30 local time this happened: https://youtu.be/6ZDEO75mR8w This was a northern Taurid, as bright as the full moon, visible for 7 seconds. Shallow entry angle and it fully disintegrated 60 km above ground. -- Steinar Midtskogen __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Fireball 'as bright as full moon' spotted in night sky over Japan
Some more videos of the fireball off the Swedish west coast: http://norskmeteornettverk.no/bilder/2020/videos-20201128.mp4 The full moon is visible in a couple of the videos, which gives an idea of the brightness. It was visible for more than 10 seconds. -- Steinar __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Fireball 'as bright as full moon' spotted in night sky over Japan
Another one peaking much, much brighter than the full moon last night: http://norskmeteornettverk.no/wordpress/?p=3187 http://norskmeteornettverk.no/bilder/2020/ildkule-20201128.mp4 http://norskmeteornettverk.no/meteor/20201128/173801/trondheim/cam1/trondheim-20201128173757-gnomonic.mp4 Apparently quite audible along the coast north of Gothenburg, Sweden. Visible from most of southern Sweden, southern Norway and Denmark desipite cloudy conditions most places. Shallow angle, possibly around 13 km/s entry speed. It went to sea, though. -Steinar drtanuki via Meteorite-list writes: > Fireball 'as bright as full moon' spotted in night sky over Japan > > https://english.kyodonews.net/news/2020/11/1630e7941a64-fireball-as-bright-as-full-moon-spotted-in-night-sky-over-japan.html > __ > > Visit our Facebook page https://www.facebook.com/meteoritecentral and the > Archives at http://www.meteorite-list-archives.com > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > https://pairlist3.pair.net/mailman/listinfo/meteorite-list __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Norwegian Sea fireball 2016-12-06
Hello, Old news, but: http://norskmeteornettverk.no/bilder/2016/video-20161206.mp4 A pity it fell over the ocean. -- Steinar __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Geminids
I reprojected each of the 108 exposures moving the radiant to the centre and stacked them (I also removing noise and aurora, so some faint meteors were probably lost), and the resulting image is: http://norskmeteornettverk.no/bilder/2015/geminidene-radiant.png -Steinar Steinar Midtskogen via Meteorite-list writes: > Hello, > > The Geminids surely didn't fail this year. I've made this composite > image of last night's catch: > > http://norskmeteornettverk.no/bilder/2015/geminide-2015.jpg > > Observed from Solobservatoriet, Harestua, Norway. > > A couple of geminids reached an altitude of 33 km and could even have > dropped tiny fragments. __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Geminids
Hello, The Geminids surely didn't fail this year. I've made this composite image of last night's catch: http://norskmeteornettverk.no/bilder/2015/geminide-2015.jpg Observed from Solobservatoriet, Harestua, Norway. A couple of geminids reached an altitude of 33 km and could even have dropped tiny fragments. -- Steinar Midtskogen __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Daytime meteor observed by the Norwegian meteor network
Thank you, and in case anyone is interested I can give some technical details for the network that we're currently building in Norway. We do not use allsky cameras, but rather a combination of wide angle cameras. We currently use four 5 MP IP cameras to cover the entire sky. Each record video in 2560x1920 resolution, 5 frames per second (we can increase that to 10 frames per second, but due to some technical issues we don't then get continuous exposure). This setup gives us better resolution in particular near the horizon where most meteors are seen, and I believe it also works better in winter conditions. The cameras are calibrating using the Hugin/panotools software (written for panorama stitching but works well for us as well!) and astrometry.net. The grid you see was made from a model of the lens based on a few thousand star positions. We obtain an accuracy of a few arc minutes in many cases. Hugin/panotools also make it trivial to change the projection of the images into a gnonomic projection (which straightens the meteor paths), making analysis much more convenient. We run the software on credit card size computers (currently Odroid XU4), simplifying maintenance and keeping costs down. Video gets stored on cheap external hard drives (a few TB can store a couple of months of video). We currently have three stations, but more are on their way and we cooperate (observations and software) with the Swedish, Danish and Finnish networks. Here's an example of a Taurid detected by all three stations last night: http://norskmeteornettverk.no/meteor/20151122/173455/ This is work in progress. Meteor detections are automatically reported to this page: http://norskmeteornettverk.no/meteor/ -Steinar ian macleod writes: > Hi Steinar Midtskogen, thank you for sharing this data and superb cam > image! A very clear daytime fireball indeed! Not to worry that the > stones for this one landed at sea, eventually one will be detected and > meteorite(s) will be located. These all European networks and the > Desert networks being built on large scale here in Australia are the > cutting edge of Meteoritics! Exciting times to not just find > meteorites but to also back track them to their parent bodies in our > solar system. The grid system on the cam image is nice, I like it! You > may have already seen the work being done in Australia, mainly Western > and South Australia. The project is called the DFN or Desert Fireball > Network. Upon completion it will consist of 50-70 cameras spread > across about 1/3 of Australia. The DFN data is streamed to the Czech > Republic researchers and also to the Australian network leader Prof > Phil Bland in Perth. Information is or will be processed via a super > computer in WA also that is used for the Square Kilometer Array. > http://fireballsinthesky.com.au/ Thank you again for sharing your > website and info, keep us updated! Kind Regards Ian Macleod > > > * This email has been sent from a virus-free computer protected by > Avast. > www.avast.com > > * __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Daytime meteor observed by the Norwegian meteor network
http://norskmeteornettverk.no/meteor/20151122/101502/ Unfortunately, only recorded by one camera (manual inspection has so far not revealed anything) and the end azimuth likely puts any meteorites in the sea southwest of Mandal, Norway's southernmost point. -- Steinar __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Possible meteorite dropper south of Stockholm, Sweden
Widely observed in a radius of at least 600 km: http://norskmeteornettverk.no/meteor/20151023/165824/ http://www.astro.uu.se/~meteor/UAA/data/trigger/event2015-10-23-18-58-31/ -- Steinar Midtskogen __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Norway Bolide Meteor 12AUG2015 w/ Video Likely Produced Meteorites!
More images/videos: http://norskmeteornettverk.no/bilder/2015/tinn-20150812-gnomonic-grid.jpg http://norskmeteornettverk.no/bilder/2015/tonsberg-20150812.jpg http://www.astro.uu.se/~meteor/meteor_20150813-0151.avi http://norskmeteornettverk.no/meteor/20150812/235039/voksenlia/cam3/voksenlia-20150812235039-gnomonic.mp4 http://norskmeteornettverk.no/bilder/2015/bergen-20150812.jpg https://www.youtube.com/watch?v=_KS28TiyqQI Yes, small fragments dropped from ~28 km quite likely. -Steinar drtanuki via Meteorite-list writes: > List, > Norway Bolide Meteor 12AUG2015 w/ Video > Likely Produced Meteorites! > > > http://lunarmeteoritehunters.blogspot.jp/2015/08/norway-bolide-meteor-12aug2015-w-video.html > > > Dirk Ross...Tokyo > The Latest Worldwide Meteor/Meteorite News > http://lunarmeteoritehunters.blogspot.com/ > __ > > Visit our Facebook page https://www.facebook.com/meteoritecentral and > the Archives at http://www.meteorite-list-archives.com > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > https://pairlist3.pair.net/mailman/listinfo/meteorite-list __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Bright bolide near the Swedish/Norwegian border
At 23:50:39UTC 2015-08-12 a bright bolide appeared in Scandinavia. Not a Perseid, but observed by many Perseid observers. It lasted 9 seconds, bright as the full moon for about 6 seconds and peaked around -14 at 100 km distance. It fragmented into two groups and faded in a spray. Green and yellow colour. A preliminary analysis gives: Incidence about 22 degrees. Terminal height about 30 km. Average speed about 17 km/s. Pictures and videos at: http://norskmeteornettverk.no/wordpress/?p=2112 -- Steinar Midtskogen __ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Huh? PhD has a Meteor? over Houston, TX? Looks like an aircraft contrail to me.
Meteors, or perhaps more frequently space junk, can move over the horizon for a few minutes, but what gives this away is that the sun has just set near the "fireball". It's getting dark on the ground, whilst the contrail is still in the light of the setting sun making it an impressive sight. The aircraft might be too far away to be seen. We see a lot of reports, pictures and videos like this every winter here in Norway since the short winter days are really a long sunrise and sunset blended, so such sights are common, and frequently misinterpreted. -Steinar drtanuki via Meteorite-list writes: > List, > > Huh? Physics/Astronomy PhD has a Meteor? over Houston, TX? > Looks like an aircraft contrail to me. Tell me that I am wrong. > Expert explains strange fireball flying over Houston area > KHOU > A slow moving meteor can make one full swing around the world before > crashing or disintegrating. The fireball Sterling captures is similar > to the one ... > http://www.khou.com/story/news/local/2015/01/21/expert-explains-strange-fireball-flying-over-houston-area/22088689/ > > > Dirk Ross...Tokyo > __ > > Visit the Archives at http://www.meteorite-list-archives.com > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > https://pairlist3.pair.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
[meteorite-list] Space junk re-entry over Svalbard
http://norskmeteornettverk.no/wordpress/?p=1820 -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] A Managua, Nicaragua meteorite?
Without ruling out that this is indeed a meteorite impact, I take the near miss of asteroid 2014 RC rather as an argument against than for. Given the news exposure that the asteroid has had, early investigators might have jumped to conclusions. We should wait for more evidence. The impact seems to have taken place about 13 hours before the closest approach. That places it half a million km away or so. The link seems to be a stretch. -Steinar "Sterling K. Webb via Meteorite-list" writes: > Kevin, List, > > It looks a great deal like the Carancas > crater, although it's a little smaller, > about 80% of its size. The test would be: > are there meteorites scattered about? __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] GA NC TN AL KY Meteor Approx 2320 EDT // 2220 CDT 02AUG2014
Anne Black via Meteorite-list writes: > But is it? > Or is all our modern fancy equipment all for naught? Well, most recently the two Annama meteorites so far found were located primarily based on photographic evidence (i.e. "modern fancy equipment") in pretty difficult and remote terrain, precisely within the predicted area for fragments of the sizes found. So hardly naught. As high resolution cameras are getting very affordable now, we should see more successful recoveries. I think it boils down to having enough people to set up and maintain such cameras, and to write better software. This is perfect for citizen science. -- Steinar Midtskogen __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://three.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Kola peninsula meteorites found
"Galactic Stone & Ironworks" writes: > The Google translation of the Finnish press release said one of the > meteorites was given the field name "Annama" after a nearby river > where it was found? Is this also the "unofficial" or generic field > name that is being used for this meteorite fall? In the Ural Federal University article, http://urfu.ru/en/news/news/5444/ "Now RAS Committee is preparing to apply to the international Meteoritical Bulletin. It is suggested that the meteorite should be called “Annama meteorite”, for it fell near Annama river." So, this is the unofficial name at the moment, but might well become the official name. The fairly elongated debris field runs in the same direction as the river, so any new finds will also likely be within a few km of the river. -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://three.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Kola peninsula meteorites found
Ural Federal University news: http://urfu.ru/en/news/news/5444/ Norwegian Meteor Network: http://norskmeteornettverk.no/wordpress/?p=1612 (Norwegian) Tähdet ja avaruus: http://www.avaruus.fi/uutiset/aurinkokunnan-pienkappaleet/suomen-tulipalloverkon-ensimmainen-meteoriitti-loytyi-itarajan-takaa.html (Finnish) Ursa press release: https://www.ursa.fi/index.php?id=6404 (Finnish) -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://three.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Murmansk Fireball
Here's a Finnish preliminary analysis: http://www.avaruus.fi/uutiset/tahtiharrastus-ja-taivaanilmiot/kuolan-tulipallon-lentorata-selvisi-putoamisalue-venajan-ja-norjan-rajan-lahella.html It seems very likely that something survived. This analysis places the expected debris area in Russia a few km from the Norwegian border. -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Murmansk Fireball
There seems to be numerous other video recordings of this fireball from Russian dashcams: http://www.youtube.com/watch?v=8OJRwIHn4rg http://www.youtube.com/watch?v=G-xsbzvR3Lk http://www.youtube.com/watch?v=AThsm7etclk I'll post something on this on the web pages of the Norwegian Meteor Network since it was seen also from Norway, but I currently have little time to track down the sources of the YouTube videos to get positions and directions. Anyone willing to help out? If this produced any meteorites, I cannot say yet whether they fell in Russia, Finland or Norway. -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Murmansk Fireball
The Norwegian Meteor Network has received a report of a fireball observed 2014-04-18 22:15UTC at 70.08482N 29.71802E towards SSW. That would place it near the Russian/Norwegian or Russian/Finnish border. Not over the sea. It was reported to illuminate the sky, but not the terrain. So probably up to full moon luminocity. Since the time agrees by 1 minute (assuming the camera was set to local Murmansk time), it's very likely the same fireball. Are there other sightings or any information about the video? -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] HUGE Meteor Sighting in Cottonwood AZ - Stats from fall
Chris Peterson writes: > The majority that produce _falls_, yes, but not _finds_, I think. That > is, your typical find (either a single individual or several pieces) > probably didn't come from a spectacular meteor event. Of course, finds > in large strewn fields are a different matter. Yes. A meteor travelling at 11 km/s only has a 1/4 of the energy of an equally sized meteor travelling at 22 km/s. The fall of the two most recent meteorite finds in Norway can be dated, but none had reports of sound. Most of these meteorite dropping fireballs are not bright enough to be detected because of clouds or daylight, and anything audible can easily be mistaken for thunder or human activity anyway. > Atmospheric entry models demonstrate that it's not difficult for a > small body to drop a few rocks on the ground without ever depositing > the sort of energy into the atmosphere we associate with bright > fireballs lasting several seconds and producing audible acoustics at > ground level. The most recent find in Norway, a 4,5 kg chondrite, seems to have come from this innocent looking fireball, seen from about 200 km: http://norskmeteornettverk.no/bilder/2013/ildkule-20120203.mp4 The brightness normalised to 100 km distance seems to be around -10, and it was visible for 3.3 seconds, not very impressive. It was photographed by two cameras and the bearings match very well (but there is a ±25 km or so uncertainty, so there is a slight possibility that the fireball is unrelated). The speed was 13 km/s, angle of incidence 57 degrees, and it burned out between 25 and 30 km altitude. I originally dismissed it as a somewhat unlikely meteorite candidate, but when a meteorite was found by chance 16 months later, I'm much less sure and I rather lean towards that it did produce this meteorite. -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Fake Norway Rock
http://www.universetoday.com/111076/follow-up-on-skydiving-meteorite-crowdsourcing-concludes-it-was-just-a-rock/ As one of the people who tried to analyse the video before it was made public, let me add a few points: We were stuck, only left with a solution that seemed consistent with the videos, but extremely unlikely. So we went public with the videos and with the only solution that we had, asking for help. And that we got. We considered several scenarious, but could not get them to match the videos, including the debris in the chute scenario. I'd say it was the prime suspect (cf the TV interview), but I'll openly admit that I was totally unable to see how it could match the video unless teleportation was involved. Even with Occam in mind, a meteorite beats teleportation. The main problems with the debris scenario was that the rock appeared several seconds after the chute had been deployed, it was passing fast (also taking into account that it could be close to the lens), it didn't seem to accelerate as expected if it fell out of the chute, and it seemed to fall from above the chute. Our mistake was that we didn't see that debris could fall much slower than the skydiver at first and then overtake him near terminal velocity later. So when an explanation for how this is possible was given (by several people independently), along with Phil Metzger's analysis of the speed/size/distance relations, it took us very little time to accept the new solution. It was clearly the missing possibility that trumps the meteorite. So let's move on. It's safe to say there's no meteorite. -- Steinar __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
