Re: [meteorite-list] Geminids on Toutatis?
Hi Chris Thanks for your reply. Ah! You misunderstood my message. Certainly,no impacts on Toutatis could have been resolved from Earth observation; I suggested it was only remotely possible in Chang'e imagery of Toutatis, and then it wasn't too probable. As it turned out, no impacts happened during the encounter. But in future encounters of near Earth objects by spacecraft during meteor showers, it might be looked for again, but not expected. I think it was the character of Charlie Chan who once said, Strange events sometimes permit themselves the luxury of having occurred. Francis Graham On Thu, Dec 13, 2012 at 11:26 AM, Francis Graham fgra...@kent.edu wrote: Hello I am not familiar with the imaging devices on Chang e 2 as it heads for Toutatis. But the Geminids are here, and flashes of meteor impacts from showers have been recorded as they happen on the Moon. Presumably, some Geminid impacts might happen also on Toutatis during the Chang-e 2 encounter--not too likely, but not so improbable as to be discounted. Pushbroom imaging systems would probably miss it though...well, maybe. Something I suppose to look for, but not hope for. Francis Graham __ 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] Geminids on Toutatis?
Ah. Well, all asteroids show impacts. The impact rate is low because of the small cross section, but there is lots of time. Debris streams are mostly short lived- a few thousand years- so I don't know how much they contribute to asteroid impacts. And it's worth keeping in mind that there are far more debris streams that are not Earth-crossing than otherwise. Asteroids may encounter dense streams that are not associated with any showers because those streams don't impact the Earth. I'm sure that when we are able to image the surface of Toutatis at high resolution, we'll see impact structures. And it's possible that some might have been produced by Geminid debris. But most not, and I doubt there is any way to tell which streams produced which impacts. The key issue with respect to relatively short flybys is that even in the densest of debris streams, impacts on a small body like Toutatis will be very infrequent, so the odds of catching one in some sort of before/after image pair seem extremely small. Also, Geminid debris is so small that we're almost certainly talking about impact structures under a meter in size, so pretty high resolution imaging would be required. Chris *** Chris L Peterson Cloudbait Observatory http://www.cloudbait.com On 12/19/2012 2:37 AM, Francis Graham wrote: Hi Chris Thanks for your reply. Ah! You misunderstood my message. Certainly,no impacts on Toutatis could have been resolved from Earth observation; I suggested it was only remotely possible in Chang'e imagery of Toutatis, and then it wasn't too probable. As it turned out, no impacts happened during the encounter. But in future encounters of near Earth objects by spacecraft during meteor showers, it might be looked for again, but not expected. I think it was the character of Charlie Chan who once said, Strange events sometimes permit themselves the luxury of having occurred. Francis Graham __ 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] Geminids on Toutatis?
At just a few kilometers across, Toutatis is extremely unlikely to experience any Geminid impacts. Furthermore, is isn't optically resolved, so the light of any impact would be lost in the much greater light of the reflected Sun (Toutatis has the same albedo as the Moon, and we can only see meteoroid impacts on the unlit section of the Moon- possible because we can actually resolve just that part of it). Chris *** Chris L Peterson Cloudbait Observatory http://www.cloudbait.com On 12/13/2012 9:26 AM, Francis Graham wrote: Hello I am not familiar with the imaging devices on Chang e 2 as it heads for Toutatis. But the Geminids are here, and flashes of meteor impacts from showers have been recorded as they happen on the Moon. Presumably, some Geminid impacts might happen also on Toutatis during the Chang-e 2 encounter--not too likely, but not so improbable as to be discounted. Pushbroom imaging systems would probably miss it though...well, maybe. Something I suppose to look for, but not hope for. Francis Graham __ 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] Geminids on Toutatis?
Hello I am not familiar with the imaging devices on Chang e 2 as it heads for Toutatis. But the Geminids are here, and flashes of meteor impacts from showers have been recorded as they happen on the Moon. Presumably, some Geminid impacts might happen also on Toutatis during the Chang-e 2 encounter--not too likely, but not so improbable as to be discounted. Pushbroom imaging systems would probably miss it though...well, maybe. Something I suppose to look for, but not hope for. Francis Graham __ 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
