The Naked Scientists

The Naked Scientists Forum

Author Topic: Does The Moons Orbit Change In Speed When Orbiting The Earth ?  (Read 6018 times)

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Dearest Lunar-tics !

Happy Sunday ! Hope ewe all had a nice Saturday. My Dorty came back from Skiing last night and that was nice. Has your dorty or any relative recently come home from skiing ?

As a sheepy I of course luff cheese. This is why I luff the Moon because as ewe well know, this is what the Moon is made from and this is true.

As ewe know the cheesy Moon orbits the Earth. See picture which I have labelled to avoid confusion.



The Moon Orbiting The Earth- labelled to avoid confusion !

When the cheesy Moon goes away from the Sun as it orbits behind the Earth, does it's orbital speed reduce and then speed up when it appears on the other side going towards the Sun ? I'm thinking that the suns gravity must have a drag and pull factor yes?

What is the speed difference ?


Ewe see I need to know as I am lecturing at the cheese board astronomy club after dinner tonight and I know the Stilton is a pedant and will want to know.

Hope ewe can help


hugs and shmishes


mwah mwah mwah



Neil
Something Smells Cheesy
xxxxxxxxxxxxxxxxxxxxxx
« Last Edit: 27/02/2011 15:27:32 by neilep »


 

Offline Soul Surfer

  • Neilep Level Member
  • ******
  • Posts: 3345
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
Nice to see you again!.  As always you have posed an interesting problem.  What is happening as always depends on the way you look at it.  Let us first think about the earth and moon orbiting each other far from the sun they both orbit in their slightly elliptical orbits around their common centre of gravity.  Now take this assembly and put it in orbit around the sun (also slightly elliptical) now when something is in orbit the "centrifugal" force associated with the orbital angular momentum mostly balances the gravitational attraction of the sun out so the earth moon combination is always falling towards the sun but missing!  The only remaining forces are the small residual changes caused by the fact that the orbits are elliptical and the changes in the distance from the earth to the sun due to that and the earth moon orbits.  This as you can see is quite complicated but these residuals cause small regular changes in the earth and moon's orbits around each other and the sun.
 

Offline RD

  • Neilep Level Member
  • ******
  • Posts: 8132
  • Thanked: 53 times
    • View Profile
A possible leads …

Quote
... At the syzygies and quarters themselves, the main effect is on the Moon's velocity rather than its position
http://en.wikipedia.org/wiki/Variation_%28astronomy%29


http://en.wikipedia.org/wiki/Evection


[ “Evection” I thought that was when posh people got rid of squatters.  :) ]
« Last Edit: 02/03/2011 11:46:50 by RD »
 

The Naked Scientists Forum


 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums