All,

Note: Angle at descending after apogee sun precession maneuver: 4.056 deg

I have looked at the orbit 634 ATS,

IBEX_2024_007_o0634a_v001.scr,

and I approve.

The only constraint violations in

IBEX_2024_007_o0634a_v001.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2); the violations are expected.

The PL commands in the v001 ATS match those in the v002 STF,

IBEX_2024_007_o0634a_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_2024_007_o0634a_v001.oef,

and as verified with ibex_orbit.

There is one star tracker outage. The outage starts 2+ days after apogee and runs for about 18 hours. Some despinning may be required due to this outage.

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

IBEX_Orbit634_Contacts.txt,

for all contacts (3).

We are not doing battery cell balancing; we'll do it again in the next orbit.

The inertial precession maneuver at perigee of orbit 633 leaves us pointing in safe directions for the orbit 634 arc A ascending and descending sequences:

ibex_rotate -o -u 0.305878,-0.869509,-0.387805 -w ibex-sun -t 2024/01:08:06:42:02

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.305878,-0.869509,-0.387805

which is R.A. +289.381 Decl. -22.818

missing R.A. +288.593 Decl. -22.356 (ibex-sun)

error is R.A. +0.788 Decl. +0.462

for a total 0.862 deg

ibex_rotate -o -u 0.305878,-0.869509,-0.387805 -w ibex-sun -t 2024/01:12:06:42:02

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.305878,-0.869509,-0.387805

which is R.A. +289.381 Decl. -22.818

missing R.A. +293.012 Decl. -21.733 (ibex-sun)

error is R.A. +3.631 Decl. +1.085

for a total 3.531 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 +293.092 -d -21.720 -w ibex-sun -t 2024/01:12:08:30:10

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.364363,-0.854568,-0.370071

which is R.A. +293.092 Decl. -21.720

missing R.A. +293.092 Decl. -21.720 (ibex-sun)

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

for a total 0.000 deg

ibex_rotate -o -r +293.092 -d -21.720 -w ibex-sun -t 2024/01:12:10:00:16

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.364363,-0.854568,-0.370071

which is R.A. +293.092 Decl. -21.720

missing R.A. +293.158 Decl. -21.709 (ibex-sun)

error is R.A. +0.066 Decl. +0.011

for a total 0.063 deg

ibex_rotate -o -r +293.092 -d -21.720 -w ibex-sun -t 2024/01:16:10:46:11

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.364363,-0.854568,-0.370071

which is R.A. +293.092 Decl. -21.720

missing R.A. +297.385 Decl. -21.036 (ibex-sun)

error is R.A. +4.293 Decl. +0.684

for a total 4.056 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 635 apogee:

ibex_rotate -o -u 0.455654,-0.812696,-0.36318 -w ibex-sun -t 2024/01:16:13:17:54

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.455655,-0.812698,-0.363181

which is R.A. +299.278 Decl. -21.296

missing R.A. +297.498 Decl. -21.021 (ibex-sun)

error is R.A. +1.780 Decl. +0.275

for a total 1.682 deg

ibex_rotate -o -u 0.455654,-0.812696,-0.36318 -w ibex-sun -t 2024-01-21T14:02:15.341Z

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

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.455655,-0.812698,-0.363181

which is R.A. +299.278 Decl. -21.296

missing R.A. +302.989 Decl. -19.961 (ibex-sun)

error is R.A. +3.711 Decl. +1.335

for a total 3.720 deg

Lo Normal mode for the entire orbit.

There is no overlap with orbit 633 commands by manual inspection or by checking at

http://ibex.unh.edu/cgi-bin/ats.cgi.

Command Approval Checklist is attached.

Ken

On Sun, Dec 24, 2023 at 1:37 PM Perry, Timothy E [US] (SP) <Timothy.Perry@ngc.com> wrote:

All,

   Attached are the planning files for Orbit #634. Please respond to this thread with comments and approvals. Approvals are required by COB 28 Dec 2023

Please note the following:

1.        No Battery Balancing

2.        Command Load Constraint Violation Report (CCVR)

IBEX_2024_007_o0634a_v001.ccvr

# Input files:         1

#   IBEX_2024_007_o0634a_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 2024/01/08 05:02:30 UTC

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

             transition to science mode at 2024/01/12 09:30:16 UTC

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

OTHER MESSAGES

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

NO MESSAGES.

Timothy E.Perry

CRS IBEX OCO-2

Mission Operations

timothy.perry@ngc.com

Office (703) 406-5976

IBEX MOC (703)404-7470

Cell (301) 606-1430