Re: Mir seen at -0.8 degree?

Leigh Palmer (
Sat, 28 Dec 1996 21:00:54 -0800

>SKYMAP confirms an approx -0.5 degree at final sighting.
>My position is 104.5614 W, 38.9478 N and 2073 m (UT-7) if anyone
>wants to provide any inputs.  Seems that my goal of seeing Mir
>below 1 degree has been achieved.  Now will try for -1 degree!

What has SKYMAP got to do with altitude? Altitude is observable
directly. If an absurd result is attained in a computation then
one usually assumes the computation (or the observation) is in
error. Refraction will buy you, on the average, 0.5 degrees. Do
you have a true or lower horizon? If you have a true horizon you
cannot observe below an apparent altitude of zero.

If timing is your criterion for altitude you pick a strange one,
especially in light of the recent boost of Mir which should make
it a bit late if your elements are old. Apparent altitude,
especially near the horizon, is very easy to measure.