All,
We were unable to dump the SSR during the perigee contacts. The AUWA01 contact @22:00, Sept 08 was scheduled at 160k. At AOS, the NMC reported not seeing
any downlink. So, we tried to blind acq the spacecraft @160k and they still saw nothing. We then dropped the downlink data rate to 2k. At that point we did see a weak signal. It had an Eb/No of 6db. The NMC tried some offsets and that increased the downlink
signal to an Eb/No of 16. But that is still not enough margin to increase the downlink to 160k and dump the SSR. We were able to verify the maneuver was successful.
Looking for an alternative time to try to dump the SSR again I scheduled a USAK01 support from 04:30 – 05:30 at 160k. This was a blind acq support. During
the contact we never did see the spacecraft. We tried to blind acq the spacecraft @2k and the NMC reported not seeing a downlink. They tried resetting their receivers and we tried to re-command the spacecraft with no luck. The operations manager was contacted
and after he remotely logged in and checked the station, they couldn’t find anything wrong station configuration.
We did have success during the USAK01 contact @16:00, Sept 9. We acquired data at AOS and were able to change the downlink data rate from 2k to 40k. We
were able to complete CAR # 1371 Hi Background and 2024 Lo Magneto season. The Lo sweep table was changed back to normal, and the star sensor cadence was increased. The Orbit 662 ATS was uplinked.
The Contact USAK01 @07:00 on 18 Sept was extended to 2 hours to try and dump the SSR. The contact is scheduled for 320k. If successful we will have more
that enough time to dump both orbits’ data.
SSC also noted that the USAK01 station configuration had not changed between the 2 contacts. We were the only user during that period. The INP2 file was the
same file for both USAK01 contacts.
Tasks Accomplished:
CAR 1371 – Hi Background & 2024 Lo Magnetotail season
Completed Pass# 3 – Upload Lo normal sweep table & Increase Star Sensor cadence
CAR 1412 – Orbit# 662 ATS Upload
IBEX_2024_262_o0662a_v001 98 Commands
Reset Master Timer
Blind Acq script
Results from the Inertial Maneuver:
Q1 -0.66526700 ActNor.EstInrToBdy[0]
Q2 -0.01605290 ActNor.EstInrToBdy[1]
Q3 0.71690000 ActNor.EstInrToBdy[2]
Q4 0.20788700 ActNor.EstInrToBdy[3]
GPS sec 1409868300 ActNor.EstTime
UTC time
09/08/2024 22:04:46 output
MPS Diff
0.818 deg
MPS Cmd Vector X -0.96211900
MPS Cmd Vector Y 0.25357400
MPS Cmd Vector Z 0.10013600
CSS Angle TLM 0.449805
CSS Sun-Pointing Angle 0.89961
04 Sept 24 @23:30:00
CSS Angle TLM 0.858434
CSS Sun-Pointing Angle 1.716868
08 Sept 24 @23:00:00
Pre-Burn
Thruster 1 5216 04 Sept 24 @23:30:00
Thruster 2 5120
Thruster 3 5472
Thruster 4 5568
Post-Burn
Thruster 1 5488 08 Sept 24 @23:00:00
Thruster 2 5392
Thruster 3 5776
Thruster 4 5872
Number of Pulses
Thruster 1 272
Thruster 2 272
Thruster 3 304
Thruster 4 304
Thruster Pairs
Thruster 1 & 2 544
Thruster 3 & 4 608
Timothy E.Perry
CRS IBEX OCO-2
Mission Operations
Office (703) 406-5976
IBEX MOC (703)404-7470
Cell (301) 606-1430