Hi all,

I have looked at the orbit 520 ATS files,

'IBEX_2021_065_o0520a_INST_v002.scr', 'IBEX_2021_065_o0520a_BUS_v002.scr'

and I approve.

The constraint violations in

IBEX_2021_065_o0520a_INST_v002.ccvr and IBEX_2021_065_o0520a_BUS_v002.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2); and having transmissions closer than the 18000 second window. The violations are acceptable.

The PL commands in IBEX_2021_065_o0520a_INST_v002.scr

match those in the v004 STF, IBEX_2021_065_o0520a_v004.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_065_o0520a_BUS_v002.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_Orbit520_Contacts.txt,

for all contacts (3) and reset master timer in Orbit 518.

We are not doing battery cell balancing this orbit.

The intertial precession maneuver at perigee of orbit 519 left us pointing in safe directions for the orbit 519 arc A ascending and descending sequences:

ibex_rotate -o -u 0.974523,-0.201548,-0.098399 -w ibex-sun -t 2021/03:07:01:04:02

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.974523,-0.201548,-0.098399

which is R.A. +348.315 Decl. -5.647

missing R.A. +347.474 Decl. -5.394 (ibex-sun)

error is R.A. +0.841 Decl. +0.253

for a total 0.874 deg

ibex_rotate -o -u 0.974523,-0.201548,-0.098399 -w ibex-sun -t 2021/03:10:14:52:00

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.974523,-0.201548,-0.098399

which is R.A. +348.315 Decl. -5.647

missing R.A. +350.873 Decl. -3.927 (ibex-sun)

error is R.A. +2.558 Decl. +1.720

for a total 3.075 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 0.984615,-0.156282,-0.078163 -w ibex-sun -t 2021/03:10:16:35:08

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.984615,-0.156282,-0.078163

which is R.A. +350.981 Decl. -4.483

missing R.A. +350.938 Decl. -3.898 (ibex-sun)

error is R.A. +0.043 Decl. +0.585

for a total 0.586 deg

ibex_rotate -o -u 0.984615,-0.156282,-0.078163 -w ibex-sun -t 2021/03:10:18:10:14

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.984615,-0.156282,-0.078163

which is R.A. +350.981 Decl. -4.483

missing R.A. +350.999 Decl. -3.871 (ibex-sun)

error is R.A. +0.018 Decl. +0.612

for a total 0.612 deg

ibex_rotate -o -u 0.984615,-0.156282,-0.078163 -w ibex-sun -t 2021/03:15:05:33:07

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.984615,-0.156282,-0.078163

which is R.A. +350.981 Decl. -4.483

missing R.A. +354.980 Decl. -2.157 (ibex-sun)

error is R.A. +3.999 Decl. +2.326

for a total 4.620 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 521 apogee:

ibex_rotate -o -u 0.991781,-0.113543,-0.058975 -w ibex-sun -t 2021/03:15:15:17:24

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. +355.354 Decl. -2.015 (ibex-sun)

error is R.A. +1.885 Decl. +1.366

for a total 2.326 deg

ibex_rotate -o -u 0.991781,-0.113543,-0.058975 -w ibex-sun -t 2021-03-20T07:02:12

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. +359.731 Decl. -0.103 (ibex-sun)

error is R.A. +6.262 Decl. +3.278

for a total 7.065 deg

Lo Normal mode for the entire orbit.

There is no overlap with orbit 519 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: Wednesday, 2021-February-24 at 17:26
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 #520 ATS Approval (06 – 15 Mar 21)

Caution - External Email

All,

Attached are the planning files for Orbit #520

Please respond to this thread with comments and approvals.

Approvals are required by 1700 on 25 February 2021

Please note the following:

Please note that these products are a version #2 set.

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# 518 Reset Master Timer - 2021/02:25:19:45:00

APL Contact

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_065_o0520a_v002.scr

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

HARD CONSTRAINT VIOLATIONS

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

NO VIOLATIONS.

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

SOFT CONSTRAINT VIOLATIONS

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

These 2 IBX-CLC-006 errors are acceptable.

IBX-CLC-006: Planned transmission at 2021/03/15 11:58:00 UTC - 2021/03/15

13:02:00 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 5880.000 seconds)

IBX-CLC-006: Planned transmission at 2021/03/15 17:28:00 UTC - 2021/03/15

18:32:00 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 5880.000 seconds)

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

transition to science mode at 2021/03/06 22:24:25 UTC

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

transition to science mode at 2021/03/10 17:40:14 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