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
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