Hi all,

Angle at descending after apogee sun maneuver is 4.096 deg. Angle at apogee of 545 after perigee sun maneuver is 4.685 deg.

I have looked at the orbit 0544 ATS file, IBEX_2021_284_o0544a_v001.scr and I approve.

The constraint violations in IBEX_2021_284_o0544a_v001.ccvr are from the removal of the ACT_SetSpinPulseProtectEnable Enable commands. The violations are acceptable.

The PL commands in IBEX_2021_284_o0544a_v001.scr match those in the STF, IBEX_2021_284_o0544a_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_284_o0544a_v001.oef and as verified with ibex_orbit.

There is 1 star tracker outage this orbit lasting for ~6 days over both maneuvers.

The ground station command sequences are correct and the timing and bit rates match those in the contacts file, IBEX_Orbit544_Contacts.txt for all contacts (3).

No Battery Balancing this orbit.

The Inertial maneuver at perigee of orbit 0543 left us pointing in safe directions for the orbit 0544 arc A ascending and descending sequences:

ibex_rotate -o -u -0.964813,-0.237517,-0.112787 -w ibex-sun -t 2021/10:11:11:52:02

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.964813,-0.237517,-0.112787

which is R.A. +193.830 Decl. -6.476

missing R.A. +196.707 Decl. -7.124 (ibex-sun)

error is R.A. +2.877 Decl. +0.648

for a total 2.929 deg

ibex_rotate -o -u -0.964813,-0.237517,-0.112787 -w ibex-sun -t 2021/10:15:11:26:25

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.964813,-0.237517,-0.112787

which is R.A. +193.830 Decl. -6.476

missing R.A. +200.290 Decl. -8.539 (ibex-sun)

error is R.A. +6.460 Decl. +2.063

for a total 6.728 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 +200.360 -d -8.565 -w ibex-sun -t 2021/10:15:13:14:33

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.927069,-0.344037,-0.148931

which is R.A. +200.360 Decl. -8.565

missing R.A. +200.360 Decl. -8.565 (ibex-sun)

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

for a total 0.000 deg

ibex_rotate -o -r +200.360 -d -8.565 -w ibex-sun -t 2021/10:15:14:44:39

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.927069,-0.344037,-0.148931

which is R.A. +200.360 Decl. -8.565

missing R.A. +200.418 Decl. -8.587 (ibex-sun)

error is R.A. +0.058 Decl. +0.022

for a total 0.061 deg

ibex_rotate -o -r +200.360 -d -8.565 -w ibex-sun -t 2021/10:19:14:00:45

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.927069,-0.344037,-0.148931

which is R.A. +200.360 Decl. -8.565

missing R.A. +204.221 Decl. -10.069 (ibex-sun)

error is R.A. +3.861 Decl. +1.504

for a total 4.096 deg

The Sun precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 0545 apogee:

ibex_rotate -o -r +204.367 -d -10.131 -w ibex-sun -t 2021/10:19:17:33:25

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.896718,-0.406147,-0.175899

which is R.A. +204.367 Decl. -10.131

missing R.A. +204.367 Decl. -10.131 (ibex-sun)

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

for a total 0.001 deg

ibex_rotate -o -r +204.367 -d -10.131 -w ibex-sun -t 2021-10-24T12:57:17

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

points axis +1.000000,+0.000000,+0.000000

towards ECI -0.896718,-0.406147,-0.175899

which is R.A. +204.367 Decl. -10.131

missing R.A. +208.828 Decl. -11.795 (ibex-sun)

error is R.A. +4.461 Decl. +1.664

for a total 4.685 deg

There is no overlap with orbit 0543 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-September-29 at 13:08
To: Carol Weaver <carol.weaver@unh.edu>, Chubin, Eric [US] (SP) <Eric.Chubin@ngc.com>, David Heirtzler <David.Heirtzler@unh.edu>, IBEX FDG Group (ADS-IBEX@l3harris.com) <ADS-IBEX@l3harris.com>, IBEXOPS <IBEXOPS@gmail.com>, ISOC <isocops@lists.sr.unh.edu>, Ken Fairchild <fair-play@comcast.net>, Ken Fairchild (kwfairchild@gmail.com) <kwfairchild@gmail.com>, Kenneth Fairchild <Ken.Fairchild@unh.edu>, Nigel Angold <angoldconsulting@earthlink.net>, Paul Janzen <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 #544 ATS Approval (11 - 20 Oct, 2021)

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 #544. Please respond to this thread with comments and approvals.

Approvals are required by 18:00, 01 Nov 2021

Please note the following:

Apogee Sun Maneuver - 2021/10:15:12:59:33

Perigee Sun Maneuver - 2021/10:19:17:18:25

No Battery Balancing this orbit

Command Load Constraint Violation Report (CCVR)

IBEX_2021_284_o0544a_v001.ccvr

# Input files: 1

# IBEX_2021_284_o0544a_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 2021/10/11 09:13:28 UTC

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

transition to science mode at 2021/10/15 14:14:39 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