Hi Jim,

Radar observations are on the list of possible improvements.
I've not actually done much in that direction, except that I
once set up Find_Orb to figure "computed" range/range rates,
then compared them to "observed" range/range rates and verified
that the "observed minus computed" range/range rates were in
the right ballparks.

There hasn't been a really good reason (so far) to add radar
observations. I've figured that OrbFit and your CODES software
already handle them nicely, and that Find_Orb doing so would be
essentially redundant. (If anyone has a situation where it would
help for Find_Orb to handle radar data, please let me know; it
would raise the priority of adding it.)

To do it _really_ right, I'd have to modify Find_Orb's concept
of the earth's orientation. It accounts for nutation and precession
and Delta-T, of course, but not for "polar wander". And there may
be some other small effects I'm not thinking about: things you can
ignore at the accuracy level of optical data, but not at the accuracy
level of radar data. I should at least read the relevant papers and
see how much trouble I'd be getting myself into if I tried to handle
radar data. Which is a long-winded way of saying: yes, please do
pass along anything that might help this cause. I think it would be
interesting reading, even if I decide it'd be best left not
implemented in Find_Orb.

Thanks! -- Bill

Jim Baer wrote:

> Bill,
>
> In an earlier note, you mentioned that Find_Orb does not yet process
> radar observations.
>
> If that is still the case, and if you'd like to add that capability,
> let me know, and I'll be glad to share the relevant papers and code.
>
> Jim