Note: Angle at descending after the apogee sun precession maneuver: 3.920 deg

I have looked at the orbit 594 ATS,

IBEX_2023_009_o0594a_v001.scr,

and I approve.

The only constraint violations in

IBEX_2023_009_o0594a_v001.ccvr

are from the removal of the

ACT_SetSpinPulseProtectEnable Enable

commands (2); the violations are expected.

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_2023_009_o0594a_v001.oef,

and as verified with ibex_orbit.

There are two star tracker outages.  The first starts 1.5 days after 15 Re ascending and runs for about 4 hours.  The second starts 2 days after apogee and runs for about 13 hours.  Some despinning may be required due to these outages.

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

IBEX_Orbit594_Contacts.txt,

for all contacts (3).

We are doing battery cell balancing and the balancing commands are correct and offset by enough time from other commands.

The inertial precession maneuver at perigee of orbit 593 leaves us pointing in safe directions for the orbit 594 arc A ascending and descending sequences:

ibex_rotate -o -u 0.343039,-0.85779,-0.38278 -w ibex-sun -t 2023/01:10:05:19:37

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.343039,-0.857790,-0.382780

 which is     R.A. +291.797 Decl. -22.506

 missing      R.A. +290.985 Decl. -22.056 (ibex-sun)

 error is     R.A.   +0.812 Decl.  +0.450

 for a total  0.875 deg

ibex_rotate -o -u 0.343039,-0.85779,-0.38278 -w ibex-sun -t 2023/01:14:02:59:44

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.343039,-0.857790,-0.382780

 which is     R.A. +291.797 Decl. -22.506

 missing      R.A. +295.266 Decl. -21.391 (ibex-sun)

 error is     R.A.   +3.469 Decl.  +1.115

 for a total  3.405 deg

The sun precession maneuver at apogee leaves us pointing in safe directions at the time of the maneuver and for the arc B ascending and descending sequences:

ibex_rotate -o -r +295.345 -d -21.377 -w ibex-sun -t 2023/01:14:04:47:52

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.398618,-0.841571,-0.364503

 which is     R.A. +295.345 Decl. -21.377

 missing      R.A. +295.345 Decl. -21.377 (ibex-sun)

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

 for a total  0.000 deg

ibex_rotate -o -r +295.345 -d -21.377 -w ibex-sun -t 2023/01:14:06:17:58

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.398618,-0.841571,-0.364503

 which is     R.A. +295.345 Decl. -21.377

 missing      R.A. +295.412 Decl. -21.366 (ibex-sun)

 error is     R.A.   +0.067 Decl.  +0.011

 for a total  0.063 deg

ibex_rotate -o -r +295.345 -d -21.377 -w ibex-sun -t 2023/01:18:03:41:08

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.398618,-0.841571,-0.364503

 which is     R.A. +295.345 Decl. -21.377

 missing      R.A. +299.474 Decl. -20.659 (ibex-sun)

 error is     R.A.   +4.129 Decl.  +0.718

 for a total  3.920 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 595 apogee:

ibex_rotate -o -u 0.486197,-0.797708,-0.356754 -w ibex-sun -t 2023/01:18:06:20:20

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.486197,-0.797708,-0.356754

 which is     R.A. +301.362 Decl. -20.901

 missing      R.A. +299.593 Decl. -20.641 (ibex-sun)

 error is     R.A.   +1.769 Decl.  +0.260

 for a total  1.675 deg

ibex_rotate -o -u 0.486197,-0.797708,-0.356754 -w ibex-sun -t 2023-01-23T00:41:50.054Z

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

 points axis  +1.000000,+0.000000,+0.000000

 towards ECI  +0.486197,-0.797708,-0.356754

 which is     R.A. +301.362 Decl. -20.901

 missing      R.A. +304.766 Decl. -19.586 (ibex-sun)

 error is     R.A.   +3.404 Decl.  +1.315

 for a total  3.453 deg

Lo Normal mode for the entire orbit.

There is no overlap with orbit 593 commands by manual inspection or by checking at

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

Command Approval Checklist is attached.

Ken