[X] My Assistant

[angel1801]

I was using the solar system simulator for Enceladus for March 20, 2006 and I noticed something.

Cassini will be within 391,000km (at 17:00:00 UT) of almost all of the area that is poorly imaged right now. That is the area from about 20W to 150W longitude. Will this area be imaged on this orbit?

If so, one would have about 2km/pixel resolution.

[edstrick]

My arm waving understanding is that any star approaches within closer than 2 light years is very rare or statistically less than 50% chance over the age of the solar system. I'm not sure on the number but I think it's something rather surprisingly large.

And Oort cloud comets have typical aphelions of a light month or so. Part of the problem is larger orbits interact with the radial tides and vertical gravity field of the galaxy and progressively get peturbed and are eventually lost. That was an essential arguement against the proposed Nemesis sub-stellar object that hypothetically caused periodic extinctions... Such an object in an orbit with a ?27? (is that the number) million year period would last a few hundred million years and be lost to interstellar space.

Sedna... it was being discussed a bit ago in some forum... may not be an Oort cloud object.. it's in way too short period an orbit for an inner-Oort cloud object (as predicted.. NONE are known yet) yet has a perihelion way too far out for solar system planetary peturbations to have pushed it out that far. That's a big reason they are looking at late or just post nebular phase close stellar encounters from another star in the cluster or association the sun formed in.... far more likely than any encounter over the age of the solar system with a random "field" star.