Re: Thickness of Saturn's rings


Jonathan Silverlight wrote:
In message <1145648957.085673.210690@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Weatherlawyer <Weatherlawyer@xxxxxxxxxxx> writes

Seeing that there is so much solar exploration going on, might now be a
time to ask if anyone has actually pinpointed a star yet? I imagine a
distance of several astronomical units should be enough to get a
paralax measurement by now. How far is Saturn; 10?

If you mean "has a deep space probe been used to do parallax
measurements ?" the answer is "no". It's been considered, but so far the
small size of the instruments and relatively low pointing accuracy
outweigh the long baseline. Of course, measurement from Earth orbit has
been revolutionised by HIPPARCOS and GAIA should be a similar advance
over HIPPARCOS.

So the stellar distances are just as hypothetical as their heat source?

And yet interferometry has deduced the Jupiter sized planets of some
stars or doubles or whatever they are called. Or is that to do with
oscillations too, not actual geometry?

.

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