[meteorite-list] Geminids on Toutatis?
From: Chris Peterson <clp_at_meteoritecentral.com>
Date: Wed, 19 Dec 2012 08:35:50 -0700 Message-ID: <50D1DED6.5050507_at_alumni.caltech.edu> 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 Received on Wed 19 Dec 2012 10:35:50 AM PST |
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