Visibility of USSF 8 (GSSAP 5 & 6) events

From: C. Bassa via Seesat-l <seesat-l_at_satobs.org>
Date: Thu, 20 Jan 2022 17:10:50 +0100
ULA just reported a launch time of 19:00UTC tomorrow (Friday January
21) for USSF 8 launching GSSAP 5 and 6 to geostationary orbit from
CCAFS on an ATLAS V511.
https://twitter.com/ulalaunch/status/1484187249038139396

The mission overview provides the target orbit and confirms that
insertion into the transfer orbit occurs on the ascending node,
placing the geostationary circularization burn around 90 deg West some
6.5 hours after launch around 01:31UTC on January 22, 2022, almost
directly above the Galapagos Islands.
https://www.ulalaunch.com/missions/next-launch/atlas-v-ussf-8

At that time, North and South America are still in darkness or nearing
morning twilight. Hence, the geostationary circularization burn
(MES-3), the separation of both spacecraft and the subsequent
collision and contamination avoidance manouvre (CCAM) where remaining
fuel is dumped, should be visible for observers in the Americas.

Scott Tilley observed these events for a previous GSSAP launch in
2016. Read about his observations in this SeeSat-L thread:
http://www.satobs.org/seesat/Aug-2016/0104.html

Here is an estimate for the GSSAP-5 orbit around separation:
1 87001U          22022.06652778  .00000000  00000-0  00000-0 0    08
2 87001   0.0000   0.0000 0014818 351.1100  64.0000  0.99155484    06

These are the timings of the major events, assuming an on time launch
at 19:00UTC. Any delays in launch time should move these events by the
launch delay:
Launch:      2022-01-21T19:00:00
MES-2:       2022-01-21T20:09:30
MES-3:       2022-01-22T01:31:12
SEP GSSAP5:  2022-01-22T01:35:48
SEP GSSAP6:  2022-01-22T01:45:20
CCAM:        2022-01-22T02:11:40

Telescopic observations could provide quite some spectacular views and
images. Time permitting I will attempt to estimate a TLE for the
transfer orbit to allow searching for and tracking the upper stage and
payload prior to the geostationary circularization burn.

Clear skies!
    Cees
_______________________________________________
Seesat-l mailing list
http://mailman.satobs.org/mailman/listinfo/seesat-l
Received on Thu Jan 20 2022 - 10:11:31 UTC

This archive was generated by hypermail 2.4.0 : Thu Jan 20 2022 - 16:11:31 UTC