Hi all,

The angle at descending after the apogee Sun Maneuver is 4.195 deg.

I have looked at the orbit 0552 ATS file, IBEX_2021_356_o0552a_v001.scr and I approve.

The constraint violations in IBEX_2021_356_o0552a_v001.ccvr are from the removal of the ACT_SetSpinPulseProtectEnable Enable commands and 2 planned transmissions that amount to greater than the maximum transmission time. The violations are acceptable.

The PL commands in IBEX_2021_356_o0552a_v001.scr match those in the STF, IBEX_2021_356_o0552a_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_356_o0552a_v001.oef and as verified with ibex_orbit.

There is 1 star tracker outage this orbit lasting ~77 hours and overlaps with the apogee maneuver.

The ground station command sequences are correct and the timing and bit rates match those in the contacts file, IBEX_Orbit552_Contacts.txt for all contacts (4).

Battery Balancing is 90 minutes long, more than 2 hours away from payload descending macros, and more than 1 hour away from maneuver.

The inertial maneuver at perigee of orbit 0551 left us pointing in safe directions for the orbit 0552 arc A ascending and descending sequences:

ibex_rotate -o -u 0.032647,-0.912948,-0.406769 -w ibex-sun -t 2021/12:23:01:18:47

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.032647,-0.912948,-0.406769

which is R.A. +272.048 Decl. -24.002

missing R.A. +271.244 Decl. -23.451 (ibex-sun)

error is R.A. +0.804 Decl. +0.551

for a total 0.920 deg

ibex_rotate -o -u 0.032647,-0.912948,-0.406769 -w ibex-sun -t 2021/12:27:03:41:53

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.032647,-0.912948,-0.406769

which is R.A. +272.048 Decl. -24.002

missing R.A. +275.792 Decl. -23.317 (ibex-sun)

error is R.A. +3.744 Decl. +0.685

for a total 3.497 deg

The Sun 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 -r +275.874 -d -23.312 -w ibex-sun -t 2021/12:27:05:30:01

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.093986,-0.913542,-0.395738

which is R.A. +275.874 Decl. -23.312

missing R.A. +275.874 Decl. -23.312 (ibex-sun)

error is R.A. +0.000 Decl. +0.000

for a total 0.000 deg

bex_rotate -o -r +275.874 -d -23.312 -w ibex-sun -t 2021/12:27:07:00:07

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.093986,-0.913542,-0.395738

which is R.A. +275.874 Decl. -23.312

missing R.A. +275.942 Decl. -23.309 (ibex-sun)

error is R.A. +0.068 Decl. +0.003

for a total 0.062 deg

ibex_rotate -o -r +275.874 -d -23.312 -w ibex-sun -t 2021/12:31:09:38:25

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.093986,-0.913542,-0.395738

which is R.A. +275.874 Decl. -23.312

missing R.A. +280.431 Decl. -23.076 (ibex-sun)

error is R.A. +4.557 Decl. +0.236

for a total 4.195 deg

The Inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 0553 apogee:

ibex_rotate -o -u 0.194222,-0.895965,-0.399405 -w ibex-sun -t 2021/12:31:13:04:57

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.194222,-0.895965,-0.399405

which is R.A. +282.231 Decl. -23.541

missing R.A. +280.597 Decl. -23.071 (ibex-sun)

error is R.A. +1.634 Decl. +0.470

for a total 1.572 deg

ibex_rotate -o -u 0.194222,-0.895965,-0.399405 -w ibex-sun -t 2022-01-05T09:12:22

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.194222,-0.895965,-0.399405

which is R.A. +282.231 Decl. -23.541

missing R.A. +286.001 Decl. -22.608 (ibex-sun)

error is R.A. +3.770 Decl. +0.933

for a total 3.592 deg

There is no overlap with orbit 0551 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-December-9 at 13:47
To: Carol Weaver <carol.weaver@unh.edu>, Chubin, Eric [US] (SP) <Eric.Chubin@ngc.com>, David Heirtzler <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>, Kenneth Fairchild <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 #552 ATS Approval (22 Dec 2021 - 01 Jan 2022)

CAUTION: This email originated from outside of the University System. Do not click links or open attachments unless you recognize the sender and know the content is safe.

All,

Attached are the planning files for Orbit #552. Please respond to this thread with comments and approvals.

Approvals are required by COB, 12 Dec 2021

Please note the following:

Apogee Sun Maneuver - 12/27/2021 05:15:01

Battery Balancing this orbit

Begin 12/31/2021 19:00:00– End 12/31/2021 20:30:00

Command Load Constraint Violation Report (CCVR)

# Filename: IBEX_2021_356_o0552a_v001.ccvr

# File type: Command Load Constraint Violation Report (CCVR)

# Create time: 2021/343.164915

# Plan period start: 2021/356.220000

# Plan period stop: 2022/001.023000

# Default time format: UTC

# Input files: 1

# IBEX_2021_35_o0552a_v001.scr

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

HARD CONSTRAINT VIOLATIONS

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

NO VIOLATIONS.

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

SOFT CONSTRAINT VIOLATIONS

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

These IBX-CLC-006 soft constraint violations areacceptable

IBX-CLC-006: Planned transmission at 2021/12/22 22:28:00 UTC - 2021/12/22

23:32:00 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 2021/12/23 01:58:00 UTC - 2021/12/23

03:02:00 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 2021/12/22 22:45:03 UTC

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

transition to science mode at 2021/12/27 06:30:07 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