Kepler-16 secondary eclipse delays grow by 2.47 minutes per year relative to primary eclipses in 2009–2024 data

We test whether public Kepler and TESS light curves give a stable difference between the primary and secondary eclipse clock rates of Kepler-16. We extract 93 eclipse windows from 35 archive products. We fit 91 windows; two have too few fit points. A fixed coverage rule keeps 79 eclipses from 2009 May to 2024 September. The secondary delay grows relative to the primary at 2.47 ± 0.06 minutes per year. The error is a rounded statistical error from a robust clock fit. Fits with different flux products, baselines, and eclipse profiles give 2.43–2.47 minutes per year. A separate mission-offset fit gives 2.52 ± 0.10. At fixed mean eccentricity 0.15944 and the 2011 orbit orientation, the result gives an approximate apsidal rate of 84.3 ± 1.9 arcseconds per year. This conversion does not include orbit-model uncertainty. A Newtonian calculation with the rounded 2011 orbit predicts 2.775 minutes per year over the same event cycles. It is a scale check without an orbit fit or error propagation. The clock pattern was reported before. This contribution supplies an independent rate, raw column extracts, timing tables, all excluded fits, code, figures, source hashes, and reproduction instructions. It does not establish evidence for another planet.

Kepler-16 · eclipsing binaries · eclipse timing · apsidal motion · circumbinary planets · Kepler · TESS · public data · reproducible research