Four 2021–2022 TESS transits of TOI-2257 b fit the discovery clock when the transit shape is fixed

We test whether later TESS transits of TOI-2257 b follow the clock from its discovery study. We measure six complete transits in public 120-second SPOC data. Four events in sectors 40, 41, 47, and 53 are later than the discovery data. With the source transit shape fixed, their time offsets are +1.49, +10.26, −4.78, and −6.75 minutes. Residual resampling gives adopted standard errors of 18.62, 15.62, 11.07, and 9.72 minutes. Each offset is smaller than one adopted error. Their weighted common offset is −2.49 minutes. Its estimated standard error is 7.29 minutes when we include the largest source clock error allowed by the published epoch and period errors. Baseline and aperture-flux controls change individual times by at most 1.17 minutes. Selected shape changes can move one time by 14.88 minutes. Independent-residual trials also give wide timing tails. We find no resolved timing change under these shape and noise models. The result does not rule out smaller changes or signals at unobserved epochs. The package contains the original light curves, source hashes, measured times, all simulated errors, control results, figures, and code for a clean offline run.

TOI-2257 b · TIC 198485881 · TESS · transit timing · public data · residual resampling