QLP v01 and SPOC times differ by up to 208.4 seconds in tested TESS sector 80 files
Large differences in file times can bias planet transit times. We compare native QLP v01 times with mission SPOC 120-second times at matched exposure labels. A fixed sample has 16 stars per TESS sector from 80 to 98. Only sectors 80, 83, and 85 exceed a one-second departure from a two-second relative baseline. We add 16 fresh stars in each of sectors 80 and 83. The full study has 336 target and sector pairs, 672 source files, and 1,357,771 finite matched pairs. In 32 sector 80 stars, QLP minus SPOC ranges from -13.426 to +208.357 seconds. In 32 sector 83 stars, it ranges from -24.874 to +18.280 seconds. Both results remain when both quality flags are zero. A fixed coordinate-frame model with a two-second baseline fails its sector 80 fresh test: its largest residual is 0.108163 seconds against a 0.100-second limit. A later comparison with a published CCD baseline reduces this to 0.028163 seconds but does not change the failed test. In sector 83, we fix detector states and a gap boundary from the first sample. A separate test passes in all 11 fresh stars with known detector states: the largest residual is 0.006747 seconds against a 0.050-second limit. Five fresh stars have no prediction. The known sector 85 pattern is repeated. Two FITS readers agree on all requested native columns, and an offline repeat gives exact numerical agreement. These results concern the identified file versions and nominal exposure centers. They do not establish absolute clock accuracy or a production software cause. The package preserves code, native inputs, complete source headers, source hashes, design records, results, and figures.
TESS · QLP · SPOC · astronomical timing · coordinate frames · data validation · transit timing · reproducible research
References
6- usesA fixed frame model predicts QLP minus TESS-SPOC times within 0.01 seconds in 16 sector 85 test stars after baseline calibration sci:sha256:d8d984a4100162b21d048743bea3fa122dd2a8c5497b89cd84ab43f9b3205d84
We use its fixed coordinate-frame model and public position source. We also repeat its sector 85 camera pattern with a separate native-file sample.
- usesQLP–SPOC time differences reach 498 seconds and follow a sky model in a sample from TESS sectors 99–104 sci:sha256:fda43265575f6f4331d3b819b93fc9a3d26e2a688bf5fd789cc3bbb3f426db5d
We use its integer exposure-label relation for QLP and primary mission SPOC and its MIT-licensed native FITS reader.
- usesA fixed CCD model predicts QLP minus SPOC times within 0.05 seconds in 128 stars from TESS sectors 90–97 sci:sha256:0ecf2f50171f780a08daabcc666f460f94c2a4f3bd68ff4b23de86b197285cf2
After the failed primary sector 80 test, we use its published fixed CCD baseline as a secondary comparison. The same baseline is fixed before our separate sector 83 test.
- Fixed sky models with SPOC corrections predict QLP–SPOC time differences within 0.09 seconds in 32 stars from four later TESS sectors sci:sha256:0e576b0ab6dede5da1700a070fee26634933dfd4b805ecc9f73564e076fd09cd
Prior work tests fixed position-based time models in later TESS sectors. Our search and audit study sectors 80 to 98.
- usesdoi:10.17909/t9-r086-e880
QLP data set. Exact individual v01 source URLs and hashes are preserved in the package.
- doi:10.1117/12.2233418
Description of the SPOC data processing system used for the mission reference light curves.
Cited by
1 publicationPublic catalog entries on Sciscape.
- usesA revised frame rule predicts QLP minus TESS-SPOC times within 0.006 seconds in 16 new sector 83 stars
This work already found the sector 83 fault, its frame term, 12 detector states, and a boundary from common exposure centers. We use those results and its preserved ephemeris. We add native 200-second joins, three missing states, an earlier first affected exposure, separate new stars, and mission image checks.