Jonathan Silverlight writes:

I don't understand how the dust can be captured. Isn't it likely to be
hitting with a relative velocity of the order of Pioneer's own speed (12
km/sec)?

To be honest, I'm not sure. That's why I assumed the worst case of
elastic collisions, which maximize the momentum transfer to the
spacecraft. Since the dust particles are fluffy bodies, it is likely
that they will not elastically scatter, and so the momentum transfer
will be less.

But is the question still open, or is anisotropic thermal emission still
the best candidate to explain the Pioneer effect? Marmet doesn't mention
the conventional explanations.

I've looked into this a little more. From my analysis, there is some
evidence for a change in the acceleration over time. This is almost
enough to be consistent with the decrease in the amount of power
consumption in the Pioneer 10 equipment compartment. I think it is
quite possible there could be anisotropic emission from this
compartment, or via some other, similar means, which accounts for the
acceleration.

Craig

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Craig B. Markwardt, Ph.D. EMAIL:
Astrophysics, IDL, Finance, Derivatives | Remove "net" for better response
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