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Topic: Phobos and Deimos tethers
Replies: 2   Last Post: Feb 4, 2012 1:12 PM

 Messages: [ Previous | Next ]
 Hop Posts: 4 Registered: 6/10/10
Phobos and Deimos tethers
Posted: Apr 24, 2011 8:39 PM

Assume Phobos and Deimos' orbits about Mars are circular and coplanar.

Each moon has a tether. Due to gravity and so called centrifugal force
gradient, each tether lies on the line that connects its moon and
Mars' center.

All objects on a moon's tether have the same angular velocity as the
moon. If released from the tether, the object will follow an
elliptical path with Mars' center lying on a focus.

Here is a pic:
http://clowder.net/hop/TMI/PhobosDeimos.jpg

There is an ellipse both these tethers share.

Call Phobos' angular velocity Wp.
Call Deimos' angular velocity Wd
Call the eccentricity of the shared ellipse e.

Can you describe e in terms of Wp and Wd?

Date Subject Author
4/24/11 Hop
5/7/11 aaareg
2/4/12 Hop David