[meteorite-list] Video footage of the impact on the ice of Lake Chebarkul finally released
Dear list members, having seen only screen shots and incomplete footage of this video in local Russian media in the last few months I had my doubts about whether this video does in fact show the impact. Finally today I saw the icy dust cloud for the very first time! Thrilling! What a wonderful fact that the impact on the ice was actually filmed by Mr Nikolaj Mel'nikov's security camera located in Chebarkul at the shore of the lake. http://www.youtube.com/watch?v=MYNPJDvTA8U Best regards Martin Postfach fast voll? Jetzt kostenlos E-Mail Adresse @t-online.de sichern und endlich Platz für tausende Mails haben. http://www.t-online.de/email-kostenlos __ 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
[meteorite-list] Video footage of the impact on the ice of Lake Chebarkul finally released
Dear list members, having seen only screen shots and incomplete footage of this video in local Russian media in the last few months I had my doubts about whether this video does in fact show the impact. Finally today I saw the icy dust cloud for the very first time! Thrilling! What a wonderful fact that the impact on the ice was actually filmed by Mr Nikolaj Mel'nikov's security camera located in Chebarkul at the shore of the lake. http://www.youtube.com/watch?v=MYNPJDvTA8U Best regards Martin Postfach fast voll? Jetzt kostenlos E-Mail Adresse @t-online.de sichern und endlich Platz für tausende Mails haben. http://www.t-online.de/email-kostenlos __ 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
[meteorite-list] Meteorite Picture of the Day
Today's Meteorite Picture of the Day: Maslyanino Contributed by: Hanno Strufe http://www.tucsonmeteorites.com/mpod.asp __ 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
[meteorite-list] SoCal Fireball - 19:50 PST 06 November 2013
Resending... message didn't post when I sent it ~2 hours ago: Hi All, Observed a very bright (mag -12) fireball on my drive home this evening at 7:50 pm PST (3:50 UT 07 November 2013). Starting direction was to my east from latitude 33.6879 N, -117.9144 W, at an elevation of about 25 degrees, and terminus was perhaps 10-15 degrees south of east (azimuth 100-105) at about 10-degree elevation. Duration was around 3 seconds, and there were multiple flashes and fragmentation. Posted my obs to the AMS website a few minutes ago and see that there are dozens of others who have already done so. My time should be very accurate as I checked my watch within a few seconds of the end of the fireball. Call it 7:50:00 pm +/- 30 seconds. This should be easy to find on all-sky cameras, and if anything survived to the ground it is definitely over land. I'd guess somewhere east of I-15 and south of I-10. --Rob __ 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
[meteorite-list] CA large meteor event 06NOV2013
List, Over 30 reports and hundreds of people searching. http://lunarmeteoritehunters.blogspot.jp/2013/11/mbiq-detects-ca-meteor-06nov2013.html Dirk Ross...Tokyo __ 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
[meteorite-list] grains of sand
Was wondering about the statement that shooting stars we see are no bigger than grains of sand??? I here it used all the time and haven't really given it any thought. I don't buy it! I don't think a grain of sand would be able to generate enough light to be visible from earth? Has anyone actually measured these grains of sand? If so how was it done. Where did this (factoid) originate and is there any validity to it? I could see gravel sized debris producing what we see but not sand and smaller. Any one care to comment? Paul Gessler __ 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
[meteorite-list] Near-Earth Object 2013 US10 Turns Out to Be a Long-Period Comet
http://neo.jpl.nasa.gov/news/news181.html Near-Earth Object 2013 US10 Turns Out to Be a Long-Period Comet Don Yeomans and Paul Chodas NASA/JPL Near-Earth Object Program Office Updated November 6, 2013 While initial reports from the Minor Planet Center in Cambridge MA categorized object 2013 US10 as a very large near-Earth asteroid, new observations now indicate that it is, in fact, a long period comet, and it is now designated C/2013 US10 (Catalina). The comet was discovered by the Catalina Sky Survey near Tucson AZ on October 31, 2013 and linked to earlier pre-discovery Catalina observations made on September 12. The initial orbit suggested this object is a large, short period, near-Earth asteroid, as reported here yesterday. An updated orbit, issued today by the Minor Planet Center removed the September 12th observations that belong to another object and include earlier pre-discovery August and September observations made by the Catalina Sky Survey, the ISON-HD observatory in Russia and Hawaii's Pan-STARRS group. The new orbit indicates that this object is in a long-period, near parabolic orbit about the sun. Furthermore, observations made last night at the Canada-France-Hawaii telescope indicate the object is showing modest cometary activity, which means that yesterday's rough estimate for the object's size (about 20 kilometers or 12 miles) must now be completely revised. A new size estimate is not yet available, but it could very well be much smaller than yesterday's estimate. __ 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
[meteorite-list] CA AZ NV UT meteor 06NOV2013 map up w about 75 reports
List, Map and about 75 sighting reports now posted. http://lunarmeteoritehunters.blogspot.jp/2013/11/mbiq-detects-ca-meteor-06nov2013.html Dirk Ross...Tokyo __ 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
[meteorite-list] What Might Happen To Comet ISON From Here On Out?
http://www.isoncampaign.org/mmk/what-might-happen What might happen to Comet ISON from here on out? by Matthew This post was written with significant input from Dr. Carey Lisse NASA Comet ISON Observing Campaign November 5, 2013 November is here and Comet ISON is just a bit over three weeks from it closest approach to the Sun (astronomers call this perihelion). As we've said from the beginning, it is impossible to predict exactly what ISON will do. However, given numerous observations of previous comets, we do have a pretty good idea of the range of possible outcomes. Now that ISON has almost completed its journey from the Oort Cloud to within a million miles of the Sun's photosphere, it seems like a good time to go over what might happen. I've grouped the possible outcomes into three scenarios, discussed in chronological order for when we would observe them occur. It is important to note up front that no matter what happens, now that ISON has made it inside the Earth's orbit, any or all of these scenarios are scientifically exciting and we would learn a lot (although I'm clearly rooting for case 3)! Case 1: Disintegration well before perihelion The first scenario, which could theoretically happen at any time, is that ISON spontaneously disintegrates. A small fraction (less than 1%) of comets have disintegrated for no apparent reason, with C/1999 S4 LINEAR in 2000 (pictured at right) and C/2010 X1 Elenin in 2011 being two recent examples. Speculation about ISON's possible demise by disintegration has been around for months, and while these predictions have so far not come to pass, disintegration is probably far more likely during the next three weeks than it has been at any point up until now. As others have discussed, ISON's activity has not been increasing particularly quickly recently, and ISON is now reaching the region of space, within ~0.8 AU (1 AU, or astronomical unit, is the distance from the Earth to the Sun) of the Sun, where comets like 1999 S4 and Elenin disintegrated. If ISON does disintegrate in the next two weeks or so, we would likely see the central condensation get less distinct and eventually dissipate into nothing. Depending on the nature of the disintegration, the brightness of the inner coma might spike briefly then fade rapidly, or it might just gradually decrease in brightness. Since ISON is currently being observed by a tremendous variety of telescopes on Earth and around the solar system, this would be the best-observed case of cometary disruption in history and would likely contribute vast new information about how comets die. While it would be extremely disappointing to miss out on a potential naked-eye comet, the scientific return from a disintegration would be phenomenal as we will be able to learn a lot about how the comet is put together. This is particularly interesting because the formation and construction of comets is still one of the major mysteries concerning how the planets in the solar system were built. Case 2: Destruction near perihelion Assuming ISON survives the next few weeks in tact, it faces an even more daunting challenge: making it around the Sun. As you are no doubt aware, ISON will face extreme temperatures as it nears perihelion. At its closest point to the Sun, the equilibrium temperature approaches 5000 degrees Fahrenheit, hot enough to cause much of the dust and rock on ISON's surface and in its coma to vaporize. While it may seem incredible that anything can survive this inferno, the rate at which ISON will likely lose mass is relatively small compared to how big it likely is (think of how a large pile of snow can last for weeks after a snowfall, even when the outdoor temperature has gotten much warmer than freezing). Furthermore, because it is moving very fast, about 400 km/sec at perihelion, it will not spend very long at such extreme temperatures. Assuming that ISON is bigger than about 200 meters in radius (current estimates suggest it is 500-2000 m in radius), it will likely survive mass loss due to sublimation of ices alone. Unfortunately for ISON, it faces a double whammy from its proximity to the Sun: even if it survives the rapid vaporization of its exterior, it gets so close to the Sun that the Sun's gravity might actually pull it apart! I discussed this in more detail in a previous post, but simulations found that ISON is more likely to survive than be pulled apart, although there is a very real chance that it could be pulled apart by these tidal forces. If ISON is destroyed within a few hours to days of its close approach to the Sun, the most likely cause will be the temperature and gravitational stresses of the near-Sun environment. However, spontaneous disintegration (Case 1) could still be the culprit, it would just be hard to prove. In any event, if ISON meets it demise before its close approach to the Sun, it will likely be among the most spectacular
Re: [meteorite-list] First Study of Chelyabinsk Meteorite
Thanks for these interesting posts Ron. I keep hearing lines like Chelyabinsk was the largest meteoroid strike since the Tunguska event. What about Sikhote-Alin? Does anyone know if there are any accurate modellings on that fall in terms of size, weight and energy? I would be interested to see a comparison. Cheers, Jeff Kuyken Meteorites Australia www.meteorites.com.au -Original Message- From: meteorite-list-boun...@meteoritecentral.com [mailto:meteorite-list-boun...@meteoritecentral.com] On Behalf Of Ron Baalke Sent: Thursday, 7 November 2013 7:44 AM To: Meteorite Mailing List Subject: [meteorite-list] First Study of Chelyabinsk Meteorite http://news.ucdavis.edu/search/news_detail.lasso?id=10764 First study of Russian meteorite UC Davis Press Release November 6, 2013 The meteor that exploded over Chelyabinsk, Russia, in February 2013 was a wake-up call, according to a University of California, Davis, scientist who participated in analyzing the event. The work is published Nov. 7 in the journal Science by an international team of researchers. If humanity does not want to go the way of the dinosaurs, we need to study an event like this in detail, said Qing-zhu Yin, professor in the Department of Earth and Planetary Sciences at UC Davis. Chelyabinsk was the largest meteoroid strike since the Tunguska event of 1908, and, thanks to modern technology from consumer video cameras to advanced laboratory techniques, provides an unprecedented opportunity to study such an event, the authors note. The Chelyabinsk meteorite belongs to the most common type of meteorite, an ordinary chondrite. If a catastrophic meteorite strike were to occur in the future, it would most likely be an object of this type, Yin said. The team was led by Olga Popova of the Russian Academy of Sciences in Moscow, and by NASA Ames and SETI Institute meteor astronomer Peter Jenniskens, and included 57 other researchers from nine countries. Our goal was to understand all circumstances that resulted in the damaging shock wave that sent over 1,200 people to hospitals in the Chelyabinsk Oblast area that day, said Jenniskens. The explosion was equivalent to about 600 thousand tons of TNT, 150 times bigger than the 2012 Sutter's Mill meteorite in California. Based on viewing angles from videos of the fireball, the team calculated that the meteoroid entered Earth's atmosphere at just over 19 kilometers per second, slightly faster than had previously been reported. Our meteoroid entry modeling showed that the impact was caused by a 20-meter sized single chunk of rock that efficiently fragmented at 30 km altitude, Popova said. (A meteoroid is the original object; a meteor is the shooting star in the sky; and a meteorite is the object that reaches the ground.) The meteor's brightness peaked at an altitude of 29.7 km (18.5 miles) as the object exploded. For nearby observers it briefly appeared brighter than the sun and caused some severe sunburns. The team estimated that about three-quarters of the meteoroid evaporated at that point. Most of the rest converted to dust and only a small fraction (4,000 to 6,000 kilograms, or less than 0.05 percent) fell to the ground as meteorites. The dust cloud was so hot it glowed orange. The largest single piece, weighing about 650 kilograms, was recovered from the bed of Lake Chebarkul in October by a team from Ural Federal University led by Professor Viktor Grokhovsky. Shockwaves from the airburst broke windows, rattled buildings and even knocked people from their feet. Popova and Jenniskens visited over 50 villages in the area and found that the shockwave caused damage about 90 kilometers (50 miles) on either side of the trajectory. The team showed that the shape of the damaged area could be explained from the fact that the energy was deposited over a range of altitudes. The object broke up 30 kilometers up under the enormous stress of entering the atmosphere at high speed. The breakup was likely facilitated by abundant shock veins that pass through the rock, caused by an impact that occurred hundreds of millions of years ago. These veins would have weakened the original meteoroid. Yin's laboratory at UC Davis carried out chemical and isotopic analysis of the meteorites. Professor Ken Verosub, also of the Department of Earth and Planetary Sciences, measured the magnetic properties of metallic grains in the meteorite. Doug Rowland, project scientist in the Center for Molecular and Genomic Imaging at the UC Davis Department of Biomedical Engineering, contributed X-ray computed tomography scanning of the rock. Put together, these measurements confirmed that the Chelyabinsk object was an ordinary chondrite, 4,452 million years old, and that it last went through a significant shock event about 115 million years after the formation of the solar system 4,567 million years ago. That impact was at a much later date than in other known chondrites of
[meteorite-list] [AD] Rare Itutinga iron ending soon (plus other rarities)
Hello all, I have an Itutinga Brazilian iron sale ending very soon on ebay. This is a very rare iron I have never seen for sale or other collections. Itutinga 2.031g slice http://www.ebay.com/itm/331056463781 Other rarities ending soon: *Serra de Mage - fragment with crust *Para de Minas 2.89g - last slice! *Macau 0.072g slice - historic hammer cattle killer Two iron only available as shale: *Santa Catharina (very rare Ataxite) *Bendego Ebay URL: http://www.ebay.com/sch/meteorite_hunter/m.html?item=331058114115 Best Andre Moutinho http://www.meteorito.com.br __ 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] SoCal Fireball - 19:50 PST 06 November 2013
lets hope this one can be found! Michael Farmer Sent from my iPad On Nov 6, 2013, at 11:34 PM, Rob Matson mojave_meteori...@cox.net wrote: Resending... message didn't post when I sent it ~2 hours ago: Hi All, Observed a very bright (mag -12) fireball on my drive home this evening at 7:50 pm PST (3:50 UT 07 November 2013). Starting direction was to my east from latitude 33.6879 N, -117.9144 W, at an elevation of about 25 degrees, and terminus was perhaps 10-15 degrees south of east (azimuth 100-105) at about 10-degree elevation. Duration was around 3 seconds, and there were multiple flashes and fragmentation. Posted my obs to the AMS website a few minutes ago and see that there are dozens of others who have already done so. My time should be very accurate as I checked my watch within a few seconds of the end of the fireball. Call it 7:50:00 pm +/- 30 seconds. This should be easy to find on all-sky cameras, and if anything survived to the ground it is definitely over land. I'd guess somewhere east of I-15 and south of I-10. --Rob __ 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 __ 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] SoCal Fireball - 19:50 PST 06 November 2013
Yes Rob! Nice captures! About 5.5 seconds in durations! Jim On 11/6/2013 11:34 PM, Rob Matson wrote: Resending... message didn't post when I sent it ~2 hours ago: Hi All, Observed a very bright (mag -12) fireball on my drive home this evening at 7:50 pm PST (3:50 UT 07 November 2013). Starting direction was to my east from latitude 33.6879 N, -117.9144 W, at an elevation of about 25 degrees, and terminus was perhaps 10-15 degrees south of east (azimuth 100-105) at about 10-degree elevation. Duration was around 3 seconds, and there were multiple flashes and fragmentation. Posted my obs to the AMS website a few minutes ago and see that there are dozens of others who have already done so. My time should be very accurate as I checked my watch within a few seconds of the end of the fireball. Call it 7:50:00 pm +/- 30 seconds. This should be easy to find on all-sky cameras, and if anything survived to the ground it is definitely over land. I'd guess somewhere east of I-15 and south of I-10. --Rob -- Jim Wooddell jim.woodd...@suddenlink.net http://pages.suddenlink.net/chondrule/ __ 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] First Study of Chelyabinsk Meteorite
Jeff- For comparison, S-A was a 100 ton body traveling at 14 km/s, and its energy output was about 10 kT. Chelyabinsk was a 10,000 ton body traveling at 30 km/s, and its energy output was about 500 kT. So these two events were in completely different classes. Had S-A been stony, no material would have arrived at the ground above terminal velocity, and we'd treat it as a much more ordinary event. Nothing like a few craters to make a fall seem much more energetic than it actually was. Chris *** Chris L Peterson Cloudbait Observatory http://www.cloudbait.com On 11/7/2013 5:13 AM, Jeff Kuyken wrote: Thanks for these interesting posts Ron. I keep hearing lines like Chelyabinsk was the largest meteoroid strike since the Tunguska event. What about Sikhote-Alin? Does anyone know if there are any accurate modellings on that fall in terms of size, weight and energy? I would be interested to see a comparison. Cheers, Jeff Kuyken Meteorites Australia www.meteorites.com.au __ 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
[meteorite-list] Need help w/ an eBay fraudster:starchild909greg
Farmerian Logic - I don't agree so it's crap. There is only one administration, unless we have broken up into different countries. Again, I have not seen or expect the house to raise taxes so what you said is total crap. Michael Farmer __ 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] Need help w/ an eBay fraudster:starchild909greg - PLEASE STOP THREAD
Good Morning; I put the List on hold yesterday as these posts were starting and opened things back up this morning - only to see it start again. Please stop this thread - thank you. Art Jones Meteorite Central -Original Message- From: meteorite-list-boun...@meteoritecentral.com [mailto:meteorite-list-boun...@meteoritecentral.com] On Behalf Of valpar...@aol.com Sent: Thursday, November 07, 2013 8:15 AM To: meteorite-list@meteoritecentral.com Subject: [meteorite-list] Need help w/ an eBay fraudster:starchild909greg Farmerian Logic - I don't agree so it's crap. There is only one administration, unless we have broken up into different countries. Again, I have not seen or expect the house to raise taxes so what you said is total crap. Michael Farmer __ 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 __ 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] Need help w/ an eBay fraudster:starchild909greg
Do we have more than one administration? Did our government change since I was in school? Saying things because you hear them on Fox news does not make them true. I the administration about to raise taxes on collectibles? If so, it means that John Boehnor and the GOP passed it in the house. Is that happening? Adam can seem to help himself these days, with near daily political rants. Why can he follow the rules and just keep politics off the list? Swartz logic, I hate Obama so anything bad said about him is true. Michael Farmer Sent from my iPad On Nov 7, 2013, at 9:14 AM, valpar...@aol.com wrote: Farmerian Logic - I don't agree so it's crap. There is only one administration, unless we have broken up into different countries. Again, I have not seen or expect the house to raise taxes so what you said is total crap. Michael Farmer __ 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 __ 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
[meteorite-list] Hubble Astronomers Observe Bizarre Six-Tailed Asteroid (2013 P5)
http://spacetelescope.org/news/heic1320/ When is a comet not a comet? Hubble astronomers observe bizarre six-tailed asteroid 7 November 2013 [Images] Astronomers using the NASA/ESA Hubble Space Telescope have observed a unique and baffling object in the asteroid belt that looks like a rotating lawn sprinkler or badminton shuttlecock. While this object is on an asteroid-like orbit, it looks like a comet, and is sending out tails of dust into space. Normal asteroids appear as tiny points of light. But this asteroid, designated P/2013 P5, has six comet-like tails of dust radiating from it like the spokes on a wheel. It was first spotted in August of this year as an unusually fuzzy-looking object by astronomers using the Pan-STARRS 1 telescope in Hawaii [1]. Because nothing like this has ever been seen before, astronomers are scratching their heads to find an adequate explanation for its mysterious appearance. The multiple tails were discovered in Hubble images taken on 10 September 2013. When Hubble returned to the asteroid on 23 September, its appearance had totally changed. It looked as if the entire structure had swung around. We were literally dumbfounded when we saw it, said lead investigator David Jewitt of the University of California at Los Angeles, USA. Even more amazingly, its tail structures change dramatically in just 13 days as it belches out dust. That also caught us by surprise. It's hard to believe we're looking at an asteroid. One explanation for the odd appearance is that the asteroid's rotation rate increased to the point where its surface started flying apart, ejecting dust in episodic eruptions that started last spring. The team rules out an asteroid impact because a lot of dust would have been blasted into space all at once, whereas P5 has ejected dust intermittently over a period of at least five months [2]. Careful modelling by team member Jessica Agarwal of the Max Planck Institute for Solar System Research in Lindau, Germany, showed that the tails could have been formed by a series of impulsive dust-ejection events [3]. Radiation pressure from the Sun smears out the dust into streamers. Given our observations and modelling, we infer that P/2013 P5 might be losing dust as it rotates at high speed, says Agarwal. The Sun then drags this dust into the distinct tails we're seeing. The asteroid could possibly have been spun up to a high speed as pressure from the Sun's light exerted a torque on the body. If the asteroid's spin rate became fast enough, Jewitt said, the asteroid's weak gravity would no longer be able to hold it together. Dust might avalanche down towards the equator, and maybe shatter and fall off, eventually drifting into space to make a tail. So far, only a small fraction of the main mass, perhaps 100 to 1000 tonnes of dust, has been lost. The asteroid is thousands of times more massive, with a radius of up to 240 metres. Follow-up observations may show whether the dust leaves the asteroid in the equatorial plane, which would be quite strong evidence for a rotational breakup. Astronomers will also try to measure the asteroid's true spin rate. Jewitt's interpretation implies that rotational breakup may be a common phenomenon in the asteroid belt; it may even be the main way in which small asteroids die [4]. In astronomy, where you find one, you eventually find a whole bunch more, Jewitt said. This is just an amazing object to us, and almost certainly the first of many more to come. The paper from Jewitt's team appears online in the 7 November issue of The Astrophysical Journal Letters. Notes [1] The comet was discovered by Micheli et al. on 27 August 2013. It was spotted in observations from 18 August 2013. The discovery was announced in a Minor Planet Electronic Circular. [2] Agarwal calculated that the first ejection event occurred on 15 April, and the last one on 4 September 2013. Other eruptions occurred on 18 July, 24 July, 8 August, and 26 August 2013. [3] A less likely option is that this emission is a result of water ice sublimating. Water ice can survive within the asteroid belt, although only at the outskirts or if buried deep enough within a large enough asteroid to be shielded. However, P5 is likely made of metamorphic rocks, making it incapable of holding ice in the same way that comets do. This, coupled with P5's orbit and its very small size, makes it very unlikely that its mass loss would be due to ice sublimation. [4] This is not the first time that Hubble has observed a strange asteroid. In 2010, Hubble spotted a strange X-shaped asteroid (heic1016). However, unlike P/2013 P5, this was thought to have been formed by a collision. Later that year astronomers observed asteroid (596) Scheila, an object with a tail that was surrounded by a C-shaped cloud of dust (opo1113a). Again, this asteroid was thought to be the result of a collision between Scheila and a much smaller body -
Re: [meteorite-list] SoCal Fireball - 19:50 PST 06 November 2013
Yes, and can we please have a first lunar fall? Oh, and I want a piece for the Museum :) Carl * Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://meteorite.unm.edu/people/carl_agee/ On Thu, Nov 7, 2013 at 7:27 AM, Michael Farmer m...@meteoriteguy.com wrote: lets hope this one can be found! Michael Farmer Sent from my iPad On Nov 6, 2013, at 11:34 PM, Rob Matson mojave_meteori...@cox.net wrote: Resending... message didn't post when I sent it ~2 hours ago: Hi All, Observed a very bright (mag -12) fireball on my drive home this evening at 7:50 pm PST (3:50 UT 07 November 2013). Starting direction was to my east from latitude 33.6879 N, -117.9144 W, at an elevation of about 25 degrees, and terminus was perhaps 10-15 degrees south of east (azimuth 100-105) at about 10-degree elevation. Duration was around 3 seconds, and there were multiple flashes and fragmentation. Posted my obs to the AMS website a few minutes ago and see that there are dozens of others who have already done so. My time should be very accurate as I checked my watch within a few seconds of the end of the fireball. Call it 7:50:00 pm +/- 30 seconds. This should be easy to find on all-sky cameras, and if anything survived to the ground it is definitely over land. I'd guess somewhere east of I-15 and south of I-10. --Rob __ 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 __ 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 __ 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
[meteorite-list] NASA's Hubble Sees Asteroid Spouting Six Comet-Like Tails
November 7, 2013 J.D. Harrington Headquarters, Washington 202-358-5241 j.d.harring...@nasa.gov Donna Weaver/Ray Villard Space Telescope Science Institute, Baltimore, Md. 410-338-4493 / 410-338-4514 dwea...@stsci.edu / vill...@stsci.edu RELEASE 13-321 NASA's Hubble Sees Asteroid Spouting Six Comet-Like Tails Astronomers viewing our solar system's asteroid belt with NASA's Hubble Space Telescope have seen for the first time an asteroid with six comet-like tails of dust radiating from it like spokes on a wheel. Unlike all other known asteroids, which appear simply as tiny points of light, this asteroid, designated P/2013 P5, resembles a rotating lawn sprinkler. Astronomers are puzzled over the asteroid's unusual appearance. We were literally dumbfounded when we saw it, said lead investigator David Jewitt of the University of California at Los Angeles. Even more amazing, its tail structures change dramatically in just 13 days as it belches out dust. That also caught us by surprise. It's hard to believe weâre looking at an asteroid. Jewitt leads a team whose research paper appears online in the Nov. 7 issue of the Astrophysical Journal Letters. P/2013 P5 has been ejecting dust periodically for at least five months. Astronomers believe it is possible the asteroid's rotation rate increased to the point where its surface started flying apart. They do not believe the tails are the result of an impact with another asteroid because they have not seen a large quantity of dust blasted into space all at once. Scientists using the Pan-STARRS survey telescope in Hawaii announced their discovery of the asteroid Aug. 27. P/2013 P5 appeared as an unusually fuzzy-looking object. The multiple tails were discovered when Hubble was used to take a more detailed image Sept. 10. When Hubble looked at the asteroid again Sept. 23, its appearance had totally changed. It looked as if the entire structure had swung around. We were completely knocked out, Jewitt said. Careful modeling by team member Jessica Agarwal of the Max Planck Institute for Solar System Research in Lindau, Germany, showed that the tails could have been formed by a series of impulsive dust-ejection events. She calculated that dust-ejection events occurred April 15, July 18, July 24, Aug. 8, Aug. 26 and Sept. 4. Radiation pressure from the sun stretched the dust into streamers. Radiation pressure could have spun P/2013 P5 up. Jewitt said the spin rate could have increased enough that the asteroid's weak gravity no longer could hold it together. If that happened, dust could slide toward the asteroid's equator, shatter and fall off, and drift into space to make a tail. So far, only about 100 to 1,000 tons of dust, a small fraction of the P/2013 P5's main mass, has been lost. The asteroid's nucleus, which measures 1,400 feet wide, is thousands of times more massive than the observed amount of ejected dust. Astronomers will continue observing P/2013 P5 to see whether the dust leaves the asteroid in the equatorial plane. If it does, this would be strong evidence for a rotational breakup. Astronomers will also try to measure the asteroid's true spin rate. Jewitt's interpretation implies that rotational breakup must be a common phenomenon in the asteroid belt; it may even be the main way small asteroids die. In astronomy, where you find one, you eventually find a whole bunch more, Jewitt said. This is just an amazing object to us, and almost certainly the first of many more to come. Jewitt said it appears P/2013 P5 is a fragment of a larger asteroid that broke apart in a collision roughly 200 million years ago. There are many collision fragments in orbits similar to P/2013 P5's. Meteorites from these bodies show evidence of having been heated to as much as 1,500 degrees Fahrenheit. This means the asteroid likely is composed of metamorphic rocks and does not hold any ice as a comet does. For images and more information about P/2013 P5, visit: http://hubblesite.org/news/2013/52 For more information about NASA's Hubble Space Telescope, visit: http://www.nasa.gov/hubble -end- __ 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
[meteorite-list] NASA's GRAIL Mission Puts a New Face on the Moon
http://www.jpl.nasa.gov/news/news.php?release=2013-322 NASA's GRAIL Mission Puts a New Face on the Moon Jet Propulsion Laboratory November 07, 2013 Scientists using data from the lunar-orbiting twins of NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission are gaining new insight into how the face of the moon received its rugged good looks. A report on the asymmetric distribution of lunar impact basins is published in this week's edition of the journal Science. Since time immemorial, humanity has looked up and wondered what made the man in the moon, said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge. We know the dark splotches are large, lava-filled, impact basins that were created by asteroid impacts about four billion years ago. GRAIL data indicate that both the near side and the far side of the moon were bombarded by similarly large impactors, but they reacted to them much differently. Understanding lunar impact basins has been hampered by the simple fact that there is a lack of consensus on their size. Most of the largest impact basins on the near side of the moon (the moon's face) have been filled with lava flows, which hide important clues about the shape of the land that could be used for determining their dimensions. The GRAIL mission measured the internal structure of the moon in unprecedented detail for nine months in 2012. With the data, GRAIL scientists have redefined the sizes of massive impact basins on the moon. Maps of crustal thickness generated by GRAIL revealed more large impact basins on the near-side hemisphere of the moon than on the far side. How could this be if both hemispheres were, as widely believed, on the receiving end of the same number of impacts? Scientists have long known that the temperatures of the near-side hemisphere of the moon were higher than those on the far side: the abundances of the heat producing elements uranium and thorium are higher on the near side than the far side, and as a consequence, the vast majority of volcanic eruptions occurred on the moon's near-side hemisphere. Impact simulations indicate that impacts into a hot, thin crust representative of the early moon's near-side hemisphere would have produced basins with as much as twice the diameter as similar impacts into cooler crust, which is indicative of early conditions on the moon's far-side hemisphere, notes lead author Katarina Miljkovic of the Institut de Physique du Globe de Paris. The new GRAIL research is also helping redefine the concept of the late heavy bombardment, a proposed spike in the rate of crater creation by impacts about 4 billion years ago. The late heavy bombardment is based largely on the ages of large near-side impact basins that are either within, or adjacent to the dark, lava-filled basins, or lunar maria, named Oceanus Procellarum and Mare Imbrium. However, the special composition of the material on and below the surface of the near side implies that the temperatures beneath this region were not representative of the moon as a whole at the time of the late heavy bombardment. The difference in the temperature profiles would have caused scientists to overestimate the magnitude of the basin-forming impact bombardment. Work by GRAIL scientists supports the hypothesis that the size distribution of impact basins on the far-side hemisphere of the moon is a more accurate indicator of the impact history of the inner solar system than those on the near side. Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow by schoolchildren in Montana, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface. JPL, a division of the California Institute of Technology in Pasadena, Calif. managed GRAIL for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. NASA's Goddard Space Flight Center, in Greenbelt, Md., manages the Lunar Reconnaissance Orbiter. Operations of the spacecraft's laser altimeter, which provided supporting data used in this investigation, is led by the Massachusetts Institute of Technology in Cambridge. Lockheed Martin Space Systems in Denver built GRAIL. For more information about GRAIL, visit http://www.nasa.gov/grail and http://grail.nasa.gov DC Agle 818-393-9011 Jet Propulsion Laboratory, Pasadena, Calif. a...@jpl.nasa.gov Dwayne Brown 202-358-1726 Headquarters, Washington dwayne.c.br...@nasa.gov Sarah McDonnell 617-253-8923 Massachusetts Institute of Technology, Cambridge
[meteorite-list] MRO HiRISE Images: November 6, 2013
MARS RECONNAISSANCE ORBITER HIRISE IMAGES November 6, 2013 o Hints of an Ancient Shoreline in Southern Isidis Planitia http://hirise.lpl.arizona.edu/ESP_033242_1845 This area--known as the Deuteronilus contact of the Isidis Basin-- has been interpreted as a possible ancient shoreline. o Breached Rim of a Circular Depression http://hirise.lpl.arizona.edu/ESP_033243_2165 This observation shows a partially-filled impact crater with sediment flow that has breached the south rim. o Cratered Cones in Tartarus Montes http://hirise.lpl.arizona.edu/ESP_033252_2070 While most craters on Mars are generated by impacts of asteroids and comets, another process might have been at play here. o Dust Covered Channels on Tharsis Tholus http://hirise.lpl.arizona.edu/ESP_033565_1945 The flanks of Tharsis Tholus are cut by large channels, similar to those visible on other Martian shield volcanos like Arsia Mons and Elysium Mons. All of the HiRISE images are archived here: http://hirise.lpl.arizona.edu/ Information about the Mars Reconnaissance Orbiter is online at http://www.nasa.gov/mro. The mission is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, for the NASA Science Mission Directorate, Washington, D.C. Lockheed Martin Space Systems, of Denver, is the prime contractor and built the spacecraft. HiRISE is operated by the University of Arizona. Ball Aerospace and Technologies Corp., of Boulder, Colo., built the HiRISE instrument. __ 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
[meteorite-list] Mars Rover Opportunity Update: October 31 - November 5, 2013
http://marsrovers.jpl.nasa.gov/mission/status.html#opportunity OPPORTUNITY UPDATE: Maneuvering Around A Sandy Dune Field - sols 3473-3478, Oct. 31, 2013-Nov. 05, 2013: Opportunity is ascending 'Solander Point' at the rim of 'Endeavour Crater.' The rover is maintaining favorable northerly tilts for improved energy production as winter approaches. Opportunity encountered an undisturbed collection of putative Martian dust, collecting in a small ripple field. On Sol 3473 (Oct. 31, 2013), the rover made a 26 feet (8-meter) approach to the dust target, now called 'Yellow-Bellied Glider.' On Sol 3475 (Nov. 2, 2013), Opportunity used the robotic arm and collected a Microscopic Imager (MI) mosaic of the dust target and then placed the Alpha Particle X-ray Spectrometer (APXS) on the same for a multi-sol integration. On Sol 3478 (Nov. 5, 2013), Opportunity continued along Solander Point towards more outcrops with a 56 feet (17-meter) dogleg maneuver to avoid driving through the dusty ripple field. As of Sol 3478 (Nov. 5, 2013), the solar array energy production was 311 watt-hours with an atmospheric opacity (Tau) of 0.536 and a solar array dust factor of 0.491. Total odometry is 23.94 miles (38.53 kilometers). __ 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
[meteorite-list] Need some small Riker boxes (3 x 4)
Hi List, I cannot get in touch with my usual source for riker boxes. I need some of the small 3 x 4 boxes. If you have some available, or know a good source for them (not eBay), then please contact me off-list : cura...@galactic-stone.com Thanks! MikeG -- - Web - http://www.galactic-stone.com Facebook - http://www.facebook.com/galacticstone Twitter - http://twitter.com/galacticstone Pinterest - http://pinterest.com/galacticstone - __ 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
[meteorite-list] First Study of Chelyabinsk Meteorite
Hello List, Jeff inquired: I keep hearing lines like 'Chelyabinsk was the largest meteoroid strike since the Tunguska event'. What about Sikhote-Alin? Does anyone know if there are any accurate modellings on that fall in terms of size, weight and energy? Here's what was able to cull from my sources: Tunguska megatons of TNT: 10-40 (probably 15) mass (tons):7 x 10^6 (if cometary) mass (tons):3.5 x 10^4 (if stony) diameter (m): 160 (if cometary) diameter (m): 60 (if stony) speed (km/s): ca. 18 (?)+ + Sekanina's opinion: from the breakup height the object was not traveling much more than 11 km/s when it entered the atmosphere Chelyabinsk megatons of TNT: ca. 0.6 mass (tons):11,000 diameter (m): 18 speed (km/s): 19 Sikhote-Alin megatons of TNT:ca. 0.0035-0.013 mass (tons):200-500 diameter (m): 600* speed (km/s): 14 * apparent diameter of the bolide with its luminous envelope Cheers, Bernd __ 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
[meteorite-list] NASA's Orion Sees Flawless Fairing Separation in Second Test
November 7, 2013 Rachel Kraft Headquarters, Washington 202-358-1100 rachel.h.kr...@nasa.gov Brandi Dean Johnson Space Center, Houston 281-483-5111 brandi.k.d...@nasa.gov RELEASE 13-328 NASA's Orion Sees Flawless Fairing Separation in Second Test The three massive panels protecting a test version of NASA's Orion multipurpose crew vehicle successfully fell away from the spacecraft Wednesday in a test of a system that will protect Orion during its first trip to space next year. The panels, called fairings, encase Orion's service module and shield it from the heat, wind and acoustics it will experience during the spacecraft's climb into space. The service module, located directly below the crew capsule, will contain the in-space propulsion capability for orbital transfer, attitude control and high-altitude ascent aborts when Orion begins carrying humans in 2021. It also will generate and store power and provide thermal control, water and air for the astronauts. The service module will remain connected to the crew module until just before the capsule returns to Earth. During Exploration Flight Test-1 (EFT-1), the spacecraft's flight test next year, a test service module will be attached to the capsule. Hardware separation events like this are absolutely critical to the mission and some of the more complicated things we do, said Mark Geyer, Orion program manager at NASA's Johnson Space Center in Houston. We want to know we've got the design exactly right and that it can be counted on in space before we ever launch. Unlike conventional rocket fairings, these panels are designed to support half of the weight of Orion's crew module and launch abort system during launch and ascent, which improves performance, saves weight and maximizes the size and capability of the spacecraft. Each panel is 14 feet high and 13 feet wide. The fairings' work is done soon after launch. They must be jettisoned when Orion has reached an altitude of about 560,000 feet. To make that possible, six breakable joints and six explosive separation bolts are used to connect the fairing panels to the rocket and each other. In a carefully timed sequence, the joints are fired apart, followed shortly by the bolts. Once all of the pyrotechnics have detonated, six spring assemblies will push the three panels away, leaving the service and crew module exposed to space as they travel onward. This test, conducted by Orion's primary contractor, Lockheed Martin, at the company's Sunnyvale, Calif., facility, was the second test of the fairing separation system. The first occurred in June, when one of the three fairing panels did not completely detach. Engineers determined the issue was caused when the top edge of the fairing came into contact with the adapter ring and kept it from rotating away and releasing from the spacecraft. Because of the engineers' confidence in successfully eliminating the interference, they maintained plans to increase this week's test fidelity by emulating the thermal loads experienced by the fairings during ascent. They used strip heaters to heat one of the fairings to 200 degrees Fahrenheit and simulate the temperatures the panels will experience. Exploration Flight Test-1 is scheduled for September 2014. During that flight, an uncrewed Orion will launch to an altitude of 3,600 miles, more than 15 times farther into space than the International Space Station. It will orbit Earth twice before re-entering the atmosphere as fast as 20,000 mph. The data gathered during the flight will influence design decisions, authenticate existing computer models, and innovative new approaches to space systems development It also will reduce overall mission risks and costs for subsequent Orion missions to an asteroid and eventually Mars. For information about Orion and EFT-1, visit: http://www.nasa.gov/orion -end- __ 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] grains of sand
Hi Paul, If what you're saying is true, then there are many many more meteors that we are not seeing (but would be visible to instruments more sensitive than are eyes, or to astronauts in Earth orbit that are closer to the action). I think that a grain of sand is large enough to ionize enough oxygen and nitrogen atoms to make the light phenomenon visible from the ground. (In the few, lucky times that I observed an actual meteor through the eyepiece of a telescope, I noticed that they had a peculisr appearance. I was struck by the two bands of diffuse light [probably ionized gas], one on each side of an extremely thin, bright line [the ablating meteor - IAU definiton]. These bands of light may have been a reflection off of thin clouds or high-altitude ice crystals, but in any case, it only adds to our ability to see a grain of sand meteor. I have the opposite opinion, as well, about a related matter. I feel that we over-estimate the percentage of material that is ablated away during the fireball/meteor phase. (Probably is too off-subject.) I also feel that the too-often-used phrase nothing made it to the ground - it all burned-up is too ill-informed. How is it physically possible for a cobble-pebble-sandgrain to continue traveling fast enough to completely ablate down to total nothingness? It's my opinion that (depending on altitude) for all sizes of incoming debris (even at cosmic-velocity) there is a certain retardation-point where, once it is reached, ablation can no longer occur. I would not be surprised if this minimum size is in the fine-pebble grain-size range, which is certainly still findable. One way that this conjecture could be substantiated, is if there were actually a gap in the population of small meteorites between pebble and micro-spherule. Has this already been recorded in Antarctica? Out the door and on my way to Imperial County, Bob V. On Thursday, November 7, 2013 6:12 AM, Paul Gessler cetu...@shaw.ca wrote: Was wondering about the statement that shooting stars we see are no bigger than grains of sand??? I here it used all the time and haven't really given it any thought. I don't buy it! I don't think a grain of sand would be able to generate enough light to be visible from earth? Has anyone actually measured these grains of sand? If so how was it done. Where did this (factoid) originate and is there any validity to it? I could see gravel sized debris producing what we see but not sand and smaller. Any one care to comment? Paul Gessler __ 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 __ 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] Need some small Riker boxes (3 x 4)
Hi Folks, The Jensens aren't answering emails for some reason and the Indian River website has no shopping cart or way to purchase instantly. Is there a website from the 21st century that offers Riker boxes? Best regards and thanks! MikeG -- - Web - http://www.galactic-stone.com Facebook - http://www.facebook.com/galacticstone Twitter - http://twitter.com/galacticstone Pinterest - http://pinterest.com/galacticstone - On 11/7/13, Philip R. Burns p...@pibburns.com wrote: At 03:52 PM 11/7/2013, Galactic Stone Ironworks wrote: I cannot get in touch with my usual source for riker boxes. I need some of the small 3 x 4 boxes. If you have some available, or know a good source for them (not eBay), then please contact me off-list : I've used the boxes that Mike Jensen sells for many years. They are very high quality unlike many other Riker clones. http://www.jensenmeteorites.com/supplies.htm -- Philip R. Pib Burns p...@pibburns.com http://www.pibburns.com/ __ 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] grains of sand
Hi Bob, You wrote, in part: I also feel that the too-often-used phrase nothing made it to the ground - it all burned-up is too ill-informed. How is it physically possible for a cobble-pebble-sandgrain to continue traveling fast enough to completely ablate down to total nothingness? It's my opinion that (depending on altitude) for all sizes of incoming debris (even at cosmic-velocity) there is a certain retardation-point where, once it is reached, ablation can no longer occur. I would not be surprised if this minimum size is in the fine-pebble grain-size range, which is certainly still findable. One way that this conjecture could be substantiated, is if there were actually a gap in the population of small meteorites between pebble and micro-spherule. Has this already been recorded in Antarctica? It never made sense to me that every part of shattered meteoroid would vaporise. I think there would be two requirements for this to be the case: 1 - Each fragment would need to be too small to survive the ablation or further fragmentation (with each fragment being subject to this condition recursively) which prevents a final solid fragment slowing and cooling so it falls to the ground in a size and location where it can be found and identified as part of the fall. 2 - Both ablation and fragmentation depend on velocity and density of air, and the smaller the fragment the faster it loses the velocity required for ablation and further fragmentation. As far as I know, most meteorites are found via visual search, though in some cases metal detectors play a role. While I recall that there have been some studies of meteorite dust by collecting material which falls on a roof or other special collecting system, these experiments are not typically - or ever - at the site of a recent meteorite fall. Perhaps if the dust particles such as 2mm and smaller, were preserved and highly visible, such as on a white sand or salt-lake surface, they might be found. I haven't heard of anyone in the Chelyabinsk area searching for dust in the run-off from their roofs, which were generally covered in snow at the time. Dust particles would have been clearly visible on the top of the snow immediately after the fall, but I don't know of any reports of these. If the meteoroid really was 10,000 tonnes, I would have thought there would be lots of dust particles falling to the ground. The only explanation I can think of which would account for dust sized particles being evaporated entirely would be that the entire environment of high altitude air they are in was raised to the required temperature primarily by compression, and a little by friction. Still, I can't imagine how all or even most fragments could be vaporised. These dust particles could be blown far away and so be difficult to find since they would be highly dispersed. There were strong winds in the Chelyabinsk event. This would preferentially drop sand-grain sized remnants further downwind, so it would not be surprising if there was little or no dust in the main strewn field. Still, theoretically, one might expect a full distribution of meteorite sizes from the main mass down to smoke particles, with wind-driven sorting of these by size to fall different distances from Lake Cherbarkul. With the snow-bound area, wide publicity and huge volume of material, I think the Chelyabinsk event should be a good opportunity to research the fate of smaller particles. On eBay, there are fragments down to fractions of a gram. I guess it would be hard to sell grain of sand like particles, and difficult to prove they were actually part of the fall, unless by destructive testing. Surely the smoke cloud of the Chelyabinsk meteor contained some dust which would have fallen. Even micron-sized smoke particles surely settle to Earth under gravitational forces, given enough time either directly by falling or more likely by being caught in a cloud and then a raindrop and falling as rain, hail or snow. If so, then in principle filtering some air here in Australia might, in principle, find a few tiny particles of the Chelyabinsk meteoroid. All the above is based on limited knowledge, how I imagine things might work out in the upper atmosphere and how this doesn't fit well with what I know about the observations. No doubt folks on this list can do better than I can with references, observations and theories. - Robin __ 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
[meteorite-list] NC Meteor 07NOV2013
List, NC Meteor 07NOV2013 http://lunarmeteoritehunters.blogspot.jp/2013/11/mbiq-detects-nc-meteor-07nov2013.html Dirk Ross...Tokyo __ 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] NC Meteor 07NOV2013
Nothing on my camera, what direction was it?? My east is blocked. * Stuart McDaniel Lawndale, NC Secr., Cleve. Co. Astronomical Society CNPA #3622 NWS Cert. Adv. Storm Spotter IMCA #9052 Sirius Meteorites Node35 - Sentinel All Sky http://spacerocks.weebly.com * -Original Message- From: drtanuki Sent: Thursday, November 07, 2013 11:07 PM To: meteorite-list Subject: [meteorite-list] NC Meteor 07NOV2013 List, NC Meteor 07NOV2013 http://lunarmeteoritehunters.blogspot.jp/2013/11/mbiq-detects-nc-meteor-07nov2013.html Dirk Ross...Tokyo __ 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 __ 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] Need some small Riker boxes (3 x 4)
Thanks to everyone who responded. I have what I need now. :) MikeG -- - Web - http://www.galactic-stone.com Facebook - http://www.facebook.com/galacticstone Twitter - http://twitter.com/galacticstone Pinterest - http://pinterest.com/galacticstone - On 11/7/13, Galactic Stone Ironworks meteoritem...@gmail.com wrote: Hi List, I cannot get in touch with my usual source for riker boxes. I need some of the small 3 x 4 boxes. If you have some available, or know a good source for them (not eBay), then please contact me off-list : cura...@galactic-stone.com Thanks! MikeG -- - Web - http://www.galactic-stone.com Facebook - http://www.facebook.com/galacticstone Twitter - http://twitter.com/galacticstone Pinterest - http://pinterest.com/galacticstone - __ 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
[meteorite-list] Ancient tool artifacts made from meteorites?
I was wondering if anyone had ever purchased a ancient tool made from a real meteorite on a site like eBay? And also, do they ever sell things like this at Tucson? Raymond Borges spacerocks.org __ 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
[meteorite-list] Meteorite Picture of the Day
Today's Meteorite Picture of the Day: Zag Contributed by: Jean-Michel Masson http://www.tucsonmeteorites.com/mpod.asp __ 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
