NRO Atlas launch

Philip Chien (kc4yer@amsat.org)
Thu, 29 Jan 1998 13:49:39 -0400

Geeze - you think they'd have the decency to schedule this so it doesn't
occur on the same day as a shuttle undocking *and* Soyuz launch ...

I only got to watch the launch for a couple of seconds from my home, 20
miles from the Cape.  Rather cloudy too, and I'm hoping that the weather
will be better tonight for the shuttle-Mir-Soyuz pass.

Launch occured at 1:37 pm local with a planar window which started at 1:08 pm.

>From what I can determine this is the very first high inclination
Atlas-Centaur mission (e.g. > 30 degrees).  Launch azmiuth was 45 degrees.
I saw an unclassified briefing chart which clearly showed the two Centaur
burns - one to enter LEO and after a coast around the world to the Southern
hemisphere a perigee burn to put the spacecraft in to a Molinya orbit.

It's likely that there will be an outgassing of the Centaur to minimize the
chances for an explosion about 1.5 hours after launch.

There's no doubt in my mind that the mean motion will be 2.0 (e.g. 12 hour
period) because of the orbital plane and launch period moving backwards by
4.43 minutes per day.  Well the air force rounded it off to the nearest
minute, but I knew what they meant. ;-)

The Centaur performed the ascent plane changes to put itself and the
spacecraft in to a 63.4 degree inclination orbit.  That's quite clear from
the briefing charts.

I would _guess_ at an eccentricity of about .72, although Florida Today had
speculated a higher eccentricity with a fairly low perigee.  The reasons
for my estimate are to keep the spacecraft out of radiation belts as much
as possible (generally a desirable thing) and because it matches the orbits
of previous U.S. Molynia orbiting satellites.

Anyway, a challenge for anybody in the Southern hemisphere to try to view.
Good luck Tony!



Philip Chien, KC4YER
Earth News
world (in)famous writer, science fiction fan, ham radio operator,
all-around nice guy, etc.