Hi all,

I have looked at the orbit 521 ATS files,

IBEX_2021_083_o0522a_INST_V001.scr, IBEX_2021_083_o0522a_BUS_V001.scr

and I approve.

The constraint violations in

IBEX_2021_083_o0522a_BUS_v001.ccvr and IBEX_2021_083_o0522a_INST_v001.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2) and the transmissions on 2021-04-02/2021-04-03 being less than the required time apart. The violations are acceptable.

The PL commands in IBEX_2021_083_o0522a_INST_V001.scr

match those in the v002 STF, IBEX_2021_083_o0522a_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_083_o0522a_BUS_v001.oef

and as verified with ibex_orbit.

There is one star tracker outage shortly after perigee and lasting for ~34 hours.

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

IBEX_Orbit522_Contacts.txt,

for all contacts (4) and reset master timer in Orbit 520.

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

The inertial precession maneuver at perigee of orbit 521 left us pointing in safe directions for the orbit 522 arc A ascending and descending sequences:

ibex_rotate -o -u 0.999417,0.033783,0.004869 -w ibex-sun -t 2021/03:25:08:29:20

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. +4.233 Decl. +1.810 (ibex-sun)

error is R.A. +2.297 Decl. +1.531

for a total 2.760 deg

ibex_rotate -o -u 0.999417,0.033783,0.004869 -w ibex-sun -t 2021/03:28:23:33:26

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. +7.638 Decl. +3.304 (ibex-sun)

error is R.A. +5.702 Decl. +3.025

for a total 6.452 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 0.993767,0.105852,0.034969 -w ibex-sun -t 2021/03:29:01:16:34

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.993767,+0.105852,+0.034969

which is R.A. +6.080 Decl. +2.004

missing R.A. +7.703 Decl. +3.333 (ibex-sun)

error is R.A. +1.623 Decl. +1.329

for a total 2.097 deg

ibex_rotate -o -u 0.993767,0.105852,0.034969 -w ibex-sun -t 2021/03:29:02:51:40

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.993767,+0.105852,+0.034969

which is R.A. +6.080 Decl. +2.004

missing R.A. +7.764 Decl. +3.360 (ibex-sun)

error is R.A. +1.684 Decl. +1.356

for a total 2.160 deg

ibex_rotate -o -u 0.993767,0.105852,0.034969 -w ibex-sun -t 2021/04:02:13:30:13

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.993767,+0.105852,+0.034969

which is R.A. +6.080 Decl. +2.004

missing R.A. +11.694 Decl. +5.037 (ibex-sun)

error is R.A. +5.614 Decl. +3.033

for a total 6.371 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 523 apogee:

ibex_rotate -o -u 0.981968,0.176826,0.066866 -w ibex-sun -t 2021/04:02:22:08:38

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.981968,+0.176826,+0.066866

which is R.A. +10.208 Decl. +3.834

missing R.A. +12.016 Decl. +5.156 (ibex-sun)

error is R.A. +1.808 Decl. +1.322

for a total 2.235 deg

ibex_rotate -o -u 0.981968,0.176826,0.066866 -w ibex-sun -t 2021-04-07T13:44:09

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.981968,+0.176826,+0.066866

which is R.A. +10.208 Decl. +3.834

missing R.A. +16.383 Decl. +6.983 (ibex-sun)

error is R.A. +6.175 Decl. +3.149

for a total 6.906 deg

Lo Normal mode for the entire orbit.

There is no overlap with orbit 521 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: Thursday, 2021-March-11 at 12:58
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 #522 ATS Approval (25 Mar – 3 Apr 21)

Caution - External Email

All,

Attached are the planning files for Orbit #522

Please respond to this thread with comments and approvals.

Approvals are required by COB on 14 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 2021/04:03:00:30:00 – End 2021/04:03:02:00:00

# Orbit# 520 Reset Master Timer - 2021/03:16:04:15:00

Command Load Constraint Violation Report (CCVR)

IBEX_2021_083_o0522a_v001.ccvr

# Input files: 1

# IBEX_2021_083_o0522a_v001.scr

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

HARD CONSTRAINT VIOLATIONS

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

NO VIOLATIONS.

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

SOFT CONSTRAINT VIOLATIONS

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

The 2 IBX-CLC-006 violations are acceptable

IBX-CLC-006: Planned transmission at 2021/04/02 23:03:00 UTC - 2021/04/03

00:07:00 UTC is followed by one or more additional transmissions

which, when combined, exceed the maximum transmission time of 5400

seconds within a 18000-second window (total planned transmission

time this window is 7680.000 seconds)

IBX-CLC-006: Planned transmission at 2021/04/03 02:28:00 UTC - 2021/04/03

03:32:00 UTC is preceded by one or more additional transmissions

which, when combined, exceed the maximum transmission time of 5400

seconds within a 18000-second window (total planned transmission

time this window is 7680.000 seconds)

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

transition to science mode at 2021/03/25 05:28:56 UTC

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

transition to science mode at 2021/03/29 02:21:40 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