All,

Note: Angle at apogee after the perigee sun precession maneuver: 4.522 deg

I have looked at the orbit 570 ATS,

IBEX_2022_155_o0570a_v001.scr,

and I approve.

The only constraint violations in

IBEX_2022_155_o0570a_v001.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2); the violations are expected.

Ascending and descending command sequences are consistent with each other, 15 Re ascending, the apogee maneuver time and 15 Re descending as determined from the OEF,

IBEX_2022_155_o0570a_v001.oef,

and as verified with ibex_orbit.

There are three star tracker outages; 2 overlap.  The first outage starts about 30 minutes before 15 Re descending and runs for three hours.  The second and third outages overlap.  These outages start about 7.5 hours before perigee and run for about 17 hours.  No despinning should be required due to these outages.

The ground station command sequences are correct and the timing and bit rates match those in the contacts file,

IBEX_Orbit570_Contacts.txt,

for all contacts (3).

We are doing battery cell balancing and the balancing commands are correct and offset by enough time from other commands.

The inertial precession maneuver at perigee of orbit 569 leaves us pointing in safe directions for the orbit 570 arc A ascending and descending sequences:

ibex_rotate -o -u 0.313077,0.87492,0.369455 -w ibex-sun -t 2022/06:05:10:14:27
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.313077,+0.874920,+0.369455
 which is R.A. +70.311 Decl. +21.682
 missing R.A. +73.097 Decl. +22.506 (ibex-sun)
 error is R.A. +2.786 Decl. +0.824
 for a total 2.710 deg

ibex_rotate -o -u 0.313077,0.87492,0.369455 -w ibex-sun -t 2022/06:08:21:53:39
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.313077,+0.874920,+0.369455
 which is R.A. +70.311 Decl. +21.682
 missing R.A. +76.708 Decl. +22.880 (ibex-sun)
 error is R.A. +6.397 Decl. +1.198
 for a total 6.039 deg

The inertial precession maneuver at apogee leaves us pointing in safe directions at the time of the maneuver and for arc B ascending and descending sequences:

ibex_rotate -o -u 0.243462,0.893806,0.376612 -w ibex-sun -t 2022/06:08:23:36:47
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.243462,+0.893806,+0.376612
 which is R.A. +74.763 Decl. +22.124
 missing R.A. +76.784 Decl. +22.888 (ibex-sun)
 error is R.A. +2.021 Decl. +0.764
 for a total 2.017 deg

ibex_rotate -o -u 0.243462,0.893806,0.376612 -w ibex-sun -t 2022/06:09:01:11:53
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.243462,+0.893806,+0.376612
 which is R.A. +74.763 Decl. +22.124
 missing R.A. +76.853 Decl. +22.894 (ibex-sun)
 error is R.A. +2.090 Decl. +0.770
 for a total 2.079 deg

ibex_rotate -o -u 0.243462,0.893806,0.376612 -w ibex-sun -t 2022/06:13:08:24:26
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.243462,+0.893806,+0.376612
 which is R.A. +74.763 Decl. +22.124
 missing R.A. +81.353 Decl. +23.216 (ibex-sun)
 error is R.A. +6.590 Decl. +1.092
 for a total 6.178 deg

The sun precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 571 apogee:

ibex_rotate -o -r +81.465 -d +23.218 -w ibex-sun -t 2022/06:13:11:06:53
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.136394,+0.908834,+0.394231
 which is R.A. +81.465 Decl. +23.218
 missing R.A. +81.465 Decl. +23.218 (ibex-sun)
 error is R.A. +0.000 Decl. +0.000
 for a total 0.000 deg

ibex_rotate -o -r +81.465 -d +23.218 -w ibex-sun -t 2022-06-18T05:57:05.474Z
Quaternion +0.000000,+0.000000,+0.000000,+0.000000
 points axis +1.000000,+0.000000,+0.000000
 towards ECI +0.136394,+0.908834,+0.394231
 which is R.A. +81.465 Decl. +23.218
 missing R.A. +86.384 Decl. +23.407 (ibex-sun)
 error is R.A. +4.919 Decl. +0.189
 for a total 4.522 deg

 Lo Normal mode for the entire orbit.

There is no overlap with orbit 569 commands by manual inspection or by checking at


Command Approval Checklist is attached.

Ken

On 05/23/2022 1:04 PM Perry, Timothy E [US] (SP) <timothy.perry@ngc.com> wrote:


All, 

   Attached are the planning files for Orbit #570. Please respond to this thread with comments and approvals.   

Approvals are required by 1800, 26 May 2022 

  

Please note the following: 


  1. Battery Balancing this orbit 

Begin 2022/06/13 19:00:00– End 2022/06/13 20:30:00


  1. Command Load Constraint Violation Report (CCVR) 

IBEX_2022_155_o0570a_v001.ccvr 

# Input files:        

# IBEX_2022_155_o0570a_v001.scr 


========================== 

HARD CONSTRAINT VIOLATIONS 

========================== 

NO VIOLATIONS. 


========================== 

SOFT CONSTRAINT VIOLATIONS 

========================== 

IBX-CLC-016: No command to enable spin pulse protection was found after 

             transition to science mode at 2022/06/05 08:18:42 UTC 

IBX-CLC-016: No command to enable spin pulse protection was found after 

             transition to science mode at 2022/06/09 00:41:53 UTC 


============== 

OTHER MESSAGES 

============== 

NO MESSAGES.