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Coincidence of meteor strike and close asteroid approach at same time.
On Feb 27, 1:33*pm, wrote:
In sci.physics Robert Clark wrote: That video I linked to previously and ones like it may also be able to address this question: An Asteroid's Parting Shot. By Phil Plait Posted Tuesday, Feb. 19, 2013, at 8:00 AM http://www.slate.com/blogs/bad_astro...r_earth_astero... The video shows 2012 DA14 slowing moving through the frame, and meteors and artificial satellites streaking rapidly through the frame. Assuming we are able to distinguish the satellites, perhaps by knowing already their positions, perhaps we can determine if the number of meteors shown here are higher than normal. Better would be longer exposures that include at least the time period of the Russian meteor impact. *Bob Clark While people here have been speculating all sorts of nonsense, astronomers from the University of Antioquia in Medellin, Colombia have figured out where the Russian meteor came from and that it has no relationship to the other close passing asteroid. http://www.space.com/19974-russian-m...igin-size.html The Fireballs of February. Feb. 22, 2012 .... "They all hail from the asteroid belt—but not from a single location in the asteroid belt," he says. "There is no common source for these fireballs, which is puzzling." "This isn't the first time sky watchers have noticed odd fireballs in February. In fact, the "Fireballs of February" are a bit of a legend in meteor circles. "Brown explains: "Back in the 1960s and 70s, amateur astronomers noticed an increase in the number of bright, sound-producing deep- penetrating fireballs during the month of February. The numbers seemed significant, especially when you consider that there are few people outside at night in winter. Follow-up studies in the late 1980s suggested no big increase in the rate of February fireballs. Nevertheless, we've always wondered if something was going on." "Indeed, a 1990 study by astronomer Ian Holliday suggests that the 'February Fireballs' are real. He analyzed photographic records of about a thousand fireballs from the 1970s and 80s and found evidence for a fireball stream intersecting Earth's orbit in February. He also found signs of fireball streams in late summer and fall. The results are controversial, however. Even Halliday recognized some big statistical uncertainties in his results." .... http://science.nasa.gov/science-news...uaryfireballs/ Note this was from last year, not this year in regard to this February's unusual meteor and asteroid encounters. But what's key is the article notes this has been noticed in other February's. The article suggests greater number of fireballs in February. It also mentions they are typically slow, long-lasting, and penetrate deep in the atmosphere. I don't know about the slow part, but the long-lasting and deep penetration aspects could be due to larger meteors during February's. If there is an association with the 2012 DA14 asteroid, then since it has approximately a year long orbit, this could explain why the fireballs are seen frequently in February. Note it was discovered last year in February also during a close approach. Also notable as Steve Willner mentioned the two orbital crossings could result in rather close approaches on the second crossing as well: On Feb 26, 1:56 pm, (Steve Willner) wrote: ... Does this mean there are two close approaches per orbit? It doesn't necessarily have to be since where the two orbits "cross" does not mean the two bodies have to be there at the same time. Yes, exactly. Typically one body will be far away when the other is near a crossing point. if they are close at one "crossing" point, they should be relatively close at the other. About half a day away at the next crossing point, given the period of 366.24 days. That's about 400 Earth radii if I've done the arithmetic right. The distance is cumulative, so a simple estimate is that it will take another 366 years (365 orbits for the asteroid) before there's another close approach. However, the recent Earth encounter must have changed the orbit, so the simple estimate is probably wrong. There are also likely to be non-gravitational effects. This object is probably not one to worry about in the near term, but this sort of rough estimate is no substitute for a proper orbit calculation. This could explain the observation of Halliday that there seems to be a statistical increase also in late Summer and Fall. In any case, the Air Force needs to release its satellite detections of these fireballs. For one thing they might be able to detect the meteors before they have any appreciable interaction with the atmosphere. For large meteors, of oblong shape, the atmospheric interaction could alter their direction, thus giving a misleading interpretation of their original orbits. For many people the Air Force not sharing all the technical means at its disposal led to the loss of the shuttle Columbia crew. It must not be said that its keeping its meteor detections capability secret led to the loss of an entire city. Bob Clark |
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Coincidence of meteor strike and close asteroid approach at same time.
On Feb 28, 11:38*am, Robert Clark wrote:
On Feb 27, 1:33*pm, wrote: In sci.physics Robert Clark wrote: That video I linked to previously and ones like it may also be able to address this question: An Asteroid's Parting Shot. By Phil Plait Posted Tuesday, Feb. 19, 2013, at 8:00 AM http://www.slate.com/blogs/bad_astro...r_earth_astero.... The video shows 2012 DA14 slowing moving through the frame, and meteors and artificial satellites streaking rapidly through the frame.. Assuming we are able to distinguish the satellites, perhaps by knowing already their positions, perhaps we can determine if the number of meteors shown here are higher than normal. Better would be longer exposures that include at least the time period of the Russian meteor impact. *Bob Clark While people here have been speculating all sorts of nonsense, astronomers from the University of Antioquia in Medellin, Colombia have figured out where the Russian meteor came from and that it has no relationship to the other close passing asteroid. http://www.space.com/19974-russian-m...igin-size.html The Fireballs of February. Feb. 22, 2012 ... "They all hail from the asteroid belt—but not from a single location in the asteroid belt," he says. "There is no common source for these fireballs, which is puzzling." "This isn't the first time sky watchers have noticed odd fireballs in February. In fact, the "Fireballs of February" are a bit of a legend in meteor circles. "Brown explains: "Back in the 1960s and 70s, amateur astronomers noticed an increase in the number of bright, sound-producing deep- penetrating fireballs during the month of February. The numbers seemed significant, especially when you consider that there are few people outside at night in winter. Follow-up studies in the late 1980s suggested no big increase in the rate of February fireballs. Nevertheless, we've always wondered if something was going on." "Indeed, a 1990 study by astronomer Ian Holliday suggests that the 'February Fireballs' are real. He analyzed photographic records of about a thousand fireballs from the 1970s and 80s and found evidence for a fireball stream intersecting Earth's orbit in February. He also found signs of fireball streams in late summer and fall. The results are controversial, however. Even Halliday recognized some big statistical uncertainties in his results." ...http://science.nasa.gov/science-news...12/22feb_febru.... *Note this was from last year, not this year in regard to this February's *unusual meteor and asteroid encounters. But what's key is the article notes this has been noticed in other February's. *The article suggests greater number of fireballs in February. It also mentions they are typically slow, long-lasting, and penetrate deep in the atmosphere. I don't know about the slow part, but the long-lasting and deep penetration aspects could be due to larger meteors during February's. *If there is an association with the 2012 DA14 asteroid, then since it *has approximately a year long orbit, this could explain why the fireballs *are seen frequently in February. Note it was discovered last year in February also during a close approach. *Also notable as Steve Willner mentioned the two orbital crossings could result in rather close approaches on the second crossing as well: On Feb 26, 1:56 pm, (Steve Willner) wrote: ... *Does this mean there are two close approaches per orbit? It doesn't necessarily have to be since where the two orbits "cross" does not mean the two bodies have to be there at the same time. Yes, exactly. *Typically one body will be far away when the other is near a crossing point. *if they are close at one "crossing" point, they should be relatively close at the other. About half a day away at the next crossing point, given the period of 366.24 days. *That's about 400 Earth radii if I've done the arithmetic right. *The distance is cumulative, so a simple estimate is that it will take another 366 years (365 orbits for the asteroid) before there's another close approach. *However, the recent Earth encounter must have changed the orbit, so the simple estimate is probably wrong. *There are also likely to be non-gravitational effects. *This object is probably not one to worry about in the near term, but this sort of rough estimate is no substitute for a proper orbit calculation. *This could explain the observation of Halliday that there seems to be a *statistical increase also in late Summer and Fall. *In any case, the Air Force needs to release its satellite detections of these fireballs. For one thing they might be able to detect the meteors before they have any appreciable interaction with the atmosphere. For large meteors, of oblong shape, the atmospheric interaction could alter their direction, thus giving a misleading interpretation of their original orbits. *For many people the Air Force not sharing all the technical means at its disposal led to the loss of the shuttle Columbia crew. It must not be said that its keeping its meteor detections capability secret led to the loss *of an entire city. * Bob Clark Since when do mainstream oligarchs care about the rest of us? |
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Coincidence of meteor strike and close asteroid approach at same time.
Robert Clark:
For many people the Air Force not sharing all the technical means at its disposal led to the loss of the shuttle Columbia crew. It must not be said that its keeping its meteor detections capability secret led to the loss of an entire city. It doesn't matter how many people believe some nonsense about the Columbia, it's not true. Can you imagine how many hours or days in advance the AF would have to have known a meteor was going to collide with the Columbia!? Not possible. The Air Force has no "meteor detections capability," secret or otherwise, because the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. The AF does not operate the U.S. space reconnaissance program. By that token, if a meteor destroys a whole city it won't be the fault of the Air Force except in deranged minds. For each nutter who blamed the Air Force for not detecting a meteor there would be two other nutters who blamed the AF for not shooting down a UFO. We mustn't let conspiracy theorists and other nut cases run our science. -- I agree with almost everything that you have said and almost everything that you will say in your entire life. usenet *at* davidillig dawt cawm |
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Coincidence of meteor strike and close asteroid approach at same time.
On Feb 28, 3:21*pm, Davoud wrote:
Robert Clark: *For many people the Air Force not sharing all the technical means at its disposal led to the loss of the shuttle Columbia crew. It must not be said that its keeping its meteor detections capability secret led to the loss *of an entire city. It doesn't matter how many people believe some nonsense about the Columbia, it's not true. Can you imagine how many hours or days in advance the AF would have to have known a meteor was going to collide with the Columbia!? Not possible. The Air Force has no "meteor detections capability," secret or otherwise, because the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. The AF does not operate the U.S. space reconnaissance program. By that token, if a meteor destroys a whole city it won't be the fault of the Air Force except in deranged minds. For each nutter who blamed the Air Force for not detecting a meteor there would be two other nutters who blamed the AF for not shooting down a UFO. We mustn't let conspiracy theorists and other nut cases run our science. -- Needless to say, the implication was not that Columbia was destroyed by a meteor, but that the Air Force's various imaging and detection capabilities were not shared before Columbia attempted re-entry. In regards to the Air Force having meteor detection capability the Air Force has acknowledged this. Bob Clark On Feb 23, 6:09 pm, Robert Clark wrote: ... Meteor expert Clark Chapman and former astronaut Rusty Schweickart urge U.S. military to re-initiate sharing of satellite detections of meteor impacts: Russian Meteor Fallout: Military Satellite Data Should Be Shared. by Leonard David, SPACE.com’s Space Insider Columnist Date: 18 February 2013 Time: 09:03 AM EThttp://www.space.com/19846-russian-meteor-fallout-military-satellites... From links in the article, the military formerly did share this information but the policy was changed in 2009. This is important because the satellites reportedly have the capability to detect meteors down to 1 meter wide and below. This would well have the capability to determine if close asteroid flybys result in increased meteor impacts. Bob Clark |
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Coincidence of meteor strike and close asteroid approach at same time.
On Thu, 28 Feb 2013 15:21:53 -0500, Davoud wrote:
The Air Force has no "meteor detections capability," secret or otherwise, because the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. Actually, the military has superior meteor detecting capability. The DOD satellites that continuously monitor the Earth looking for covert nuclear explosions provide some of the best data available on meteors. Unfortunately, this data is only shared with the academic community on rare occasions. What the military doesn't have (and doesn't much need) is the capability of detecting meteoroids. The only practical way of detecting those is optically, and while most are too small for current technology, the most likely detectors of meteoroids are non-military sky surveys. |
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Coincidence of meteor strike and close asteroid approach at same time.
"Robert Clark" wrote in message
... For many people the Air Force not sharing all the technical means at its disposal led to the loss of the shuttle Columbia crew. In what reality? The Air Force would have gladly shared the data had it been asked for. They had done so in the past when asked. It must not be said that its keeping its meteor detections capability secret led to the loss of an entire city. Bob Clark -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net |
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Coincidence of meteor strike and close asteroid approach at same time.
Davoud:
The Air Force has no "meteor detections capability," secret or otherwise, because the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. Chris L Peterson: Actually, the military has superior meteor detecting capability. The DOD satellites that continuously monitor the Earth looking for covert nuclear explosions provide some of the best data available on meteors. So it's like I said, the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. -- I agree with almost everything that you have said and almost everything that you will say in your entire life. usenet *at* davidillig dawt cawm |
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Coincidence of meteor strike and close asteroid approach at same time.
On Feb 28, 7:27*pm, Davoud wrote:
Davoud: The Air Force has no "meteor detections capability," secret or otherwise, because the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. Chris L Peterson: Actually, the military has superior meteor detecting capability. The DOD satellites that continuously monitor the Earth looking for covert nuclear explosions provide some of the best data available on meteors. So it's like I said, the AF is not in the business of detecting meteors, even if it does so inadvertently from time to time. -- I agree with almost everything that you have said and almost everything that you will say in your entire life. usenet *at* davidillig dawt cawm In other words, our USAF isn't in the business of tracking an incoming 50 Mt nuke from Russia or any other nation. |
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Coincidence of meteor strike and close asteroid approach at same time.
On Sat, 2 Mar 2013 10:10:42 -0800 (PST), Brad Guth
wrote: In other words, our USAF isn't in the business of tracking an incoming 50 Mt nuke from Russia or any other nation. Meteors are atmospheric phenomena, lasting a few seconds. The Air Force can and does record such events (inadvertently, as Davoud pointed out) while monitoring for nuclear blasts and rocket launches. What the Air Force does not currently do (because they have little reason) is to monitor space for asteroids or meteoroids in Earth intersecting orbits. That is a task best left to civilian agencies and amateur astronomers, and the ability to detect smaller and smaller objects is steadily improving. The Air Force does monitor bodies in Earth orbit (using radar) because those are the things most likely (by far) to damage space assets, not sporadic meteoroids. |
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Coincidence of meteor strike and close asteroid approach at same time.
On Sat, 02 Mar 2013 11:23:52 -0700, Chris L Peterson
wrote: Meteors are atmospheric phenomena ....and the science studying them is called meteorology... :-) |
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