Re: Observing TDRS maneuvers

Philip Chien (kc4yer@amsat.org)
Thu, 27 Jun 1996 06:41:59 -0400

Jeff Barker <jbarker@arinc.com> stated:
>     Viewing any geostationary satellite is a challenge but I don't think
>     that the operation of the thrusters will result in any signature that
>     would help to see that TDRS satellite move.  Hydrazine is a
>     monopropellant that provides hot gas propulsion.  The gas is clear.
>     There is no orange flame.  Unless you have an IR telescope, the
>     satellite looks the same whether the thrusters are firing or not.

something to add is the hydrazine thrusters are about the size of a
thimble.  If memory serves they produce about one ounce force of thrust.
Colliqually thrusters like that are known as 'mouse-fart' thrsters.

I'd suspect that Jeff is correct and unless you're using an infrared
telescope you won't see any thruster firings from that distance.


Philip Chien, Earth News - space writer and consultant  PCHIEN@IDS.NET
   __                                 __^__          __________
  |   \                          +---/     \---+    (=========
  |____\___________              +---\_____/---+     //
  >____)|        | \__                    \  \______//___
 >/     |________|    \                   [         _____\
 >|____________________\                   \_______/
 Roger, go at throttle up         CHR$(32) the final frontier