Re: An astrodynamics question

Russell Eberst (R.Eberst@roe.ac.uk)
Mon, 25 Mar 1996 18:11:37 +0000 (GMT)

On Mon, 25 Mar 1996, Richard Clark wrote:

> >From the PRIORITIES list of reasions for interest in the objects:
> 
> >Reasons for inclusion
> 
> >(13)   evaluating 13th-order harmonics in E.g.f. at resonance
> >(14)   evaluating 14th-order harmonics in E.g.f. at resonance
> >(15)   evaluating 15th-order harmonics in E.g.f. at resonance
> >(29)   evaluating 29th-order harmonics in E.g.f. at resonance
> 
> Why are these orders singled out for study? It seems that a satellite orbit
> could have a resonance with other higher order harmonics eg 27th and possibly
> 31st.
> 
> Richard Clark
> rclark@lpl.arizona.edu
> 
> 
> 
They are not "singled out". They just happen to be those which the present
objects in the list are experiencing. 
If you have any suggestions of objects which will be undergoing resonance
in the near future we would be delighted to have them. The resonance
has to be prolonged, so that the effects build up.
 One reason for omitting some resonant objects, is that the resonance has
been studied for that inclination, in the past. For example there have been
plenty of 15th order studies done on objects at popular inclinations like
65 degrees and 81.2 degrees.
27th order at 74dgs was studied some years ago with 73-107B, which is now
back in the list at 14th order.
13th order is being studied using 85-100B, a very useful suggestion made by
Ted Molczan some years ago. Another 13th order object is 73-86AW, which
provided remarkable results. It amazed me that this "chunk of junk" had
scientific papers written about it, as it helped to provide evalution of the
Earth's gravity field.
best wishes  Russell