Polygon error for NIRCam SUB160P data in Ops B12.3 processing

[stscijirahub]

Issue JP-4372 was created on JIRA by Tyler Pauly:

JWST OPS encountered failures in Level 3 while processing some nrca4 SUB160P data, for jw07671-o57 and jw08882-o002:

2026-06-03 12:27:00,241 - stpipe.step - INFO - Step tweakreg running with args (<jwst.datamodels.library.ModelLibrary object at 0x1048520d0>,).
2026-06-03 12:27:00,300 - jwst.tweakreg.tweakreg_step - INFO - Detected 3 sources in jw07671057001_02102_00001_nrca4_cal.fits.
2026-06-03 12:27:00,368 - jwst.tweakreg.tweakreg_step - INFO - Detected 4 sources in jw07671057001_02102_00002_nrca4_cal.fits.
2026-06-03 12:27:00,436 - jwst.tweakreg.tweakreg_step - INFO - Detected 1 sources in jw07671057001_02102_00003_nrca4_cal.fits.
2026-06-03 12:27:00,504 - jwst.tweakreg.tweakreg_step - INFO - Detected 7 sources in jw07671057001_02102_00004_nrca4_cal.fits.
2026-06-03 12:27:00,569 - jwst.tweakreg.tweakreg_step - INFO - Detected 2 sources in jw07671057001_02102_00005_nrca4_cal.fits.
2026-06-03 12:27:00,637 - jwst.tweakreg.tweakreg_step - INFO - Detected 3 sources in jw07671057001_02102_00006_nrca4_cal.fits.
2026-06-03 12:27:00,705 - jwst.tweakreg.tweakreg_step - INFO - Detected 3 sources in jw07671057001_02102_00007_nrca4_cal.fits.
2026-06-03 12:27:00,720 - jwst.tweakreg.tweakreg_step - INFO -
2026-06-03 12:27:00,720 - jwst.tweakreg.tweakreg_step - INFO - Number of image groups to be aligned: 7.
2026-06-03 12:27:00,720 - tweakwcs.imalign - INFO -
2026-06-03 12:27:00,720 - tweakwcs.imalign - INFO - ***** tweakwcs.imalign.align_wcs() started on 2026-06-03 12:27:00.720397
2026-06-03 12:27:00,720 - tweakwcs.imalign - INFO -       Version 0.9.0
2026-06-03 12:27:00,720 - tweakwcs.imalign - INFO -
----------------------------------------------------------------------
ERROR RUNNING STEP 'Image3Pipeline':
    No valid polygons provided
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/stpipe/cli/strun.py", line 24, in main
    cmdline.step_from_cmdline(sys.argv[1:])
    ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/stpipe/cmdline.py", line 469, in step_from_cmdline
    step.run(*positional)
    ~~~~~~~~^^^^^^^^^^^^^
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/jwst/stpipe/core.py", line 373, in run
    result = super().run(*args)
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/stpipe/step.py", line 572, in run
    step_result = self.process(*args)
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/jwst/pipeline/calwebb_image3.py", line 85, in process
    input_models = self.tweakreg.run(input_models)
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/jwst/stpipe/core.py", line 373, in run
    result = super().run(*args)
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/stpipe/step.py", line 572, in run
    step_result = self.process(*args)
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/jwst/tweakreg/tweakreg_step.py", line 285, in process
    correctors = twk.relative_align(
        correctors,
    ...<11 lines>...
        yoffset=self.yoffset,
    )
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/stcal/tweakreg/tweakreg.py", line 72, in relative_align
    align_wcs(
    ~~~~~~~~~^
        correctors,
        ^^^^^^^^^^^
    ...<8 lines>...
        clip_accum=clip_accum,
        ^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/tweakwcs/imalign.py", line 650, in align_wcs
    gcat = WCSGroupCatalog(
        wcatalogs, name=f"GROUP ID: {group_id}", bb_policy=group_bb_policy
    )
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/tweakwcs/wcsimage.py", line 570, in __init__
    self.update_bounding_polygon()
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/tweakwcs/wcsimage.py", line 712, in update_bounding_polygon
    self._polygon = SphericalPolygon.multi_union(polygons)
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^
  File "/Users/tpauly/miniconda3/envs/JWSTDP-2.0.0-5-py313-macos-arm64/lib/python3.13/site-packages/spherical_geometry/polygon.py", line 1343, in multi_union
    raise ValueError("No valid polygons provided")
ValueError: No valid polygons provided```

Strangely, this error doesn't reproduce on (my local) jwst dev environment with tweakwcs 0.9.0, stcal/main and jwst/main. It may be that if this error is restricted to this particular subarray, we may just wait until B13.0 for it to automagically resolve. Any other option would require a patch, which seems unlikely given our position in the build timeline.

That said, I'm filing this ticket to at least track down why the error is seen and track its prevalence.