Hi all,

I have looked at the orbit 0526 ATS files, IBEX_2021_120_o0526a_BUS_v001.scr, IBEX_2021_120_o0526a_INST_v001.scr and I approve.

The constraint violations in IBEX_2021_120_o0526a_BUS_v001.ccvr and IBEX_2021_120_o0526a_INST_v001.ccvr

are from the removal of the ACT_SetSpinPulseProtectEnable Enable commands. The violations are acceptable.

The PL commands in IBEX_2021_120_o0526a_INST_v001.scr match those in the STF, IBEX_2021_120_o0526a_v002.stf

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_2021_120_o0526a_BUS_v001.oef and as verified with ibex_orbit.

There is one star tracker outage lasting for ~9.5 hours ending about an hour before the perigee maneuver takes place.

The ground station command sequences are correct and the timing and bit rates match those in the contacts file, IBEX_Orbit526_Contacts.txt for all contacts (3).

No Battery Balancing this orbit

The Inertial maneuver at perigee of orbit 0525 left us pointing in safe directions for the orbit 0526 arc A ascending and descending sequences:

ibex_rotate -o -u 0.788422,0.567896,0.236397 -w ibex-sun -t 2021/04:30:23:09:39

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.788423,+0.567896,+0.236397

which is R.A. +35.765 Decl. +13.674

missing R.A. +38.079 Decl. +14.951 (ibex-sun)

error is R.A. +2.314 Decl. +1.277

for a total 2.580 deg

ibex_rotate -o -u 0.788422,0.567896,0.236397 -w ibex-sun -t 2021/05:04:18:09:36

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.788423,+0.567896,+0.236397

which is R.A. +35.765 Decl. +13.674

missing R.A. +41.804 Decl. +16.121 (ibex-sun)

error is R.A. +6.039 Decl. +2.447

for a total 6.327 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 0.738961,0.622087,0.258735 -w ibex-sun -t 2021/05:04:19:52:44

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.738961,+0.622087,+0.258735

which is R.A. +40.092 Decl. +14.995

missing R.A. +41.874 Decl. +16.143 (ibex-sun)

error is R.A. +1.782 Decl. +1.148

for a total 2.065 deg

ibex_rotate -o -u 0.738961,0.622087,0.258735 -w ibex-sun -t 2021/05:04:21:27:50

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.738961,+0.622087,+0.258735

which is R.A. +40.092 Decl. +14.995

missing R.A. +41.939 Decl. +16.163 (ibex-sun)

error is R.A. +1.847 Decl. +1.168

for a total 2.128 deg

ibex_rotate -o -u 0.738961,0.622087,0.258735 -w ibex-sun -t 2021/05:09:11:36:25

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.738961,+0.622087,+0.258735

which is R.A. +40.092 Decl. +14.995

missing R.A. +46.319 Decl. +17.418 (ibex-sun)

error is R.A. +6.227 Decl. +2.423

for a total 6.451 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 0527 apogee:

ibex_rotate -o -u 0.683656,0.673118,0.282007 -w ibex-sun -t 2021/05:09:17:31:42

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.683656,+0.673118,+0.282007

which is R.A. +44.555 Decl. +16.380

missing R.A. +46.547 Decl. +17.469 (ibex-sun)

error is R.A. +1.992 Decl. +1.089

for a total 2.194 deg

ibex_rotate -o -u 0.683656,0.673118,0.282007 -w ibex-sun -t 2021-05-14T12:26:56

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.683656,+0.673118,+0.282007

which is R.A. +44.555 Decl. +16.380

missing R.A. +51.317 Decl. +18.707 (ibex-sun)

error is R.A. +6.762 Decl. +2.327

for a total 6.853 deg

There is an overlap with orbit 0525 commands where the Science command and LO_SCIENCE_MODE are sent before a contact in the 0525 ATS. This is acceptable.

Command Approval Checklist is attached.

Carol

Carol Weaver

University of New Hampshire

503.902.8492

From: Perry, Timothy E [US] (SP) <Timothy.Perry@ngc.com>
Date: Wednesday, 2021-April-14 at 12:03
To: Weaver, Carol <Carol.Weaver@unh.edu>, Chubin, Eric [US] (SP) <Eric.Chubin@ngc.com>, Heirtzler, David <David.Heirtzler@unh.edu>, ADS-IBEX@l3harris.com <ADS-IBEX@l3harris.com>, IBEXOPS@gmail.com <IBEXOPS@gmail.com>, isocops@lists.sr.unh.edu <isocops@lists.sr.unh.edu>, fair-play@comcast.net <fair-play@comcast.net>, kwfairchild@gmail.com <kwfairchild@gmail.com>, Fairchild, Kenneth <Ken.Fairchild@unh.edu>, angoldconsulting@earthlink.net <angoldconsulting@earthlink.net>, Paul.Janzen@mso.umt.edu <Paul.Janzen@mso.umt.edu>, Perry, Timothy E [US] (SP) <Timothy.Perry@ngc.com>, Tyler, Ryan S [US] (SP) <Ryan.Tyler@ngc.com>, Wesley, Sheral R [US] (SP) <Sheral.Wesley@ngc.com>, Wynn, Reese [US] (SP) <Reese.Wynn@ngc.com>
Subject: IBEX Orbit #526 ATS Approval ( 30 Apr – `10 May 21)

Caution - External Email

All,

Attached are the planning files for Orbit #526. Please respond to this thread with comments and approvals.

Approvals are required by COB on 19 April 2021

Please note the following:

I generated 3 separate ATS files BUS, INST and a complete file. The BUS and INST will be the files to be uplinked. The complete ATS, I used as a sanity check to see how the commands lined up. Since we are in a new phase of ATS generation. IF you have any ideas of doing this differently, let me know.

The 3 ATS files have been changed to word files and encrypted. I will send out another email with the password. The files that have been transferred via MFT have not been encrypted and are still text files.

I moved the 2 House Keeping commands from the INST ATS to the BUS ATS. I commented out the 2 commands in the INST ATS. If for some reason we were unable to uplink the INST Commands for this orbit, we would have been in the wrong spacecraft state for executing the maneuver commands.

No Battery Balancing this orbit

# Orbit# 524 Reset Master Timer - 2021/04:21:20:15:00

Command Load Constraint Violation Report (CCVR)

IBEX_2021_120_o0526a_v001.ccvr

# Input files: 1

# IBEX_2021_120_1500_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 2021/04/30 19:12:26 UTC

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

transition to science mode at 2021/05/04 20:57:50 UTC

==============

OTHER MESSAGES

==============

NO MESSAGES.

Timothy E.Perry

CRS IBEX OCO-2

Mission Operations

timothy.perry@ngc.com

Office (703) 406-5976

Cell (301) 606-1430