hi Brent,
thank's for the link, all good I hope,
opened face book account for the astronomy course,
also, too the right area, now sit back and study,
regards,
Peter.
Well I've taken the plunge and signed up too. I was never any good at study, so I'll see how far I can go. So far the reading hasn't been to bad, just need to brush up on my algebra.
Do you mean the equation in Point 3 (solving for 'G')? If so, yes. From memory we did that level of algebra in high school.
Yes, although I think they are requiring you to solve for D, unless my understanding of algebra terminology is completely wrong, which is a very real possibility. The solution is given, I just can't work to it from the original equation.
It likely is high school algebra, but high school is somewhere I haven't been for a very long time.
It likely is high school algebra, but high school is somewhere I haven't been for a very long time.
Hi Malc,
Sorry if my comment came across wrong, it was meant as an encouragement (i.e. they don't appear to require a uni degree as a prequisite for this course). It's been a long time since I was at school too
I'm happy to provide a worked example if it helps.
Ahh ... I wasn't aware that cuberoot(x) was the same as x^1/3, I was a lot closer to solving it than I thought. There may yet be hope for me!
mprenzler, absolutely no offense taken, I didn't read it in the negative at all.
mithrandir, thanks for the workings, super helpful. Although obvious in retrospect, the reciprocate step didn't occur to me and so my workings were a little more long winded.
hi All,
Mick & Barry,
I see the result of the equasion
that you both have solved,
what is D standing for in the equasion?,
as it has been along time since I was at high school, not too much of this was going on when I was there, so I have a lot of learning and understanding too do,
there again, may be alot of tuition too,
regards,
Peter.
The Roche limit for a rigid spherical satellite excluding orbital effects, is the distance, , from the primary at which the gravitational force on a test mass on the surface of the object is exactly equal to the tidal force pulling the object away from the object:
and further down the page:
Quote:
This is the orbital distance inside of which loose material (e.g., regolith or loose rocks) on the surface of the satellite closest to the primary would be pulled away
If I understand this correctly, if the surface of the moon were inside the Roche Limit (i.e. if the diameter of its orbit was less than the value of d calculated for the earth and the moon), then anything on the surface of the moon would be pulled towards earth.
hi Michael,
thank you,
I understand the mechanics of what is going on,
the equasions are the tricky ones, and I shall be trying to
work it out, still studying,
regards,
Peter.
Good Stuff guys !!! 
