Hi all,

I have looked at the orbit 521 ATS files,

IBEX_2021_074_o0521a_INST_v001.scr, IBEX_2021_074_o0521a_BUS_v001.scr

and I approve.

The constraint violations in

IBEX_2021_074_o0521a_BUS_v001.ccvr and IBEX_2021_074_o0521a_INST_v001.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2). The violations are acceptable.

The PL commands in IBEX_2021_074_o0521a_INST_v001.scr

match those in the v002 STF, IBEX_2021_074_o0521a_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_074_o0521a_BUS_v001.oef

and as verified with ibex_orbit.

There are no star tracker outages.

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

IBEX_Orbit521_Contacts.txt,

for all contacts (5) and reset master timer in Orbit 519.

We are doing battery cell balancing this orbit and it is appropriately placed.

The inertial precession maneuver at perigee of orbit 520 left us pointing in safe directions for the orbit 521 arc A ascending and descending sequences:

ibex_rotate -o -u 0.991781,-0.113543,-0.058975 -w ibex-sun -t 2021/03:16:02:07:13

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.991781,-0.113543,-0.058975

which is R.A. +353.469 Decl. -3.381

missing R.A. +355.787 Decl. -1.846 (ibex-sun)

error is R.A. +2.318 Decl. +1.535

for a total 2.778 deg

ibex_rotate -o -u 0.991781,-0.113543,-0.058975 -w ibex-sun -t 2021/03:19:19:32:40

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.991781,-0.113543,-0.058975

which is R.A. +353.469 Decl. -3.381

missing R.A. +359.297 Decl. -0.299 (ibex-sun)

error is R.A. +5.828 Decl. +3.082

for a total 6.590 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 0.99883,-0.039419,-0.028009 -w ibex-sun -t 2021/03:19:21:15:48

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.998830,-0.039419,-0.028009

which is R.A. +357.740 Decl. -1.605

missing R.A. +359.362 Decl. -0.269 (ibex-sun)

error is R.A. +1.622 Decl. +1.336

for a total 2.101 deg

ibex_rotate -o -u 0.99883,-0.039419,-0.028009 -w ibex-sun -t 2021/03:19:22:50:54

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.998830,-0.039419,-0.028009

which is R.A. +357.740 Decl. -1.605

missing R.A. +359.422 Decl. -0.242 (ibex-sun)

error is R.A. +1.682 Decl. +1.363

for a total 2.165 deg

ibex_rotate -o -u 0.99883,-0.039419,-0.028009 -w ibex-sun -t 2021/03:24:11:25:31

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.998830,-0.039419,-0.028009

which is R.A. +357.740 Decl. -1.605

missing R.A. +3.419 Decl. +1.496 (ibex-sun)

error is R.A. +354.321 Decl. +3.101

for a total 6.470 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 522 apogee:

ibex_rotate -o -u 0.999417,0.033783,0.004869 -w ibex-sun -t 2021/03:24:19:56:06

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.999417,+0.033783,+0.004869

which is R.A. +1.936 Decl. +0.279

missing R.A. +3.739 Decl. +1.618 (ibex-sun)

error is R.A. +1.803 Decl. +1.339

for a total 2.246 deg

ibex_rotate -o -u 0.999417,0.033783,0.004869 -w ibex-sun -t 2021-03-29T11:02:26

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.999417,+0.033783,+0.004869

which is R.A. +1.936 Decl. +0.279

missing R.A. +8.073 Decl. +3.498 (ibex-sun)

error is R.A. +6.137 Decl. +3.219

for a total 6.926 deg

Lo Normal mode for the entire orbit.

There is no overlap with orbit 520 commands.

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: Tuesday, 2021-March-2 at 15:09
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>, 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 #521 ATS Approval (15 - 25 Mar 21

Caution - External Email

All,

Attached are the planning files for Orbit #521

Please respond to this thread with comments and approvals.

Approvals are required by COB on 05 March 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.
Battery Balancing this orbit

Begin 2021/03:24:23:30:00– End 2021/03:25:01:00:00

# Orbit# 519 Reset Master Timer - 2021/03:06:19:45:00

APL Contact 2021-03-24,083,22:00:00 - 2021-03-24,083,23:00:00

Just a reminder for the APL contact. We start off at 2k D\L, after 5 minutes we switch to 320k D\L, Then 5 minutes later we start the SSR Dump with Dump New command

Command Load Constraint Violation Report (CCVR)

IBEX_2021_074_o0521a_v001.ccvr

# Input files: 1

# IBEX_2021_074_o0521a_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 2021/03/15 22:57:28 UTC

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

transition to science mode at 2021/03/19 22:20:54 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