A symmetric fit to the 25 April 2025 TESS transit of K2-24 b agrees with the 2024 forecast

We test a 2024 transit forecast with public TESS Sector 91 data for K2-24 b. The data cover the full transit on 25 April 2025, including ingress and egress. A symmetric, exposure-integrated trapezoid fit to 1080 two-minute samples gives BJD_TDB 2460791.39602 with an empirical error estimate of 0.00239 day (3.44 minutes). The observed time is 6.14 minutes later than the final CDS forecast, or 1.72 combined standard errors. Baseline, flux, and plausible transit-shape checks support this result. Four residual block lengths each have 1500 bootstrap fits. The adopted error is the largest bootstrap or independent-noise estimate. This single event gives no strong evidence against the forecast and does not establish an extra planet. The error is conditional on a symmetric transit, a smooth local baseline, and the tested residual noise. We preserve both raw TESS products, the numeric forecast table, input hashes, source code, all fit checks, figures, and instructions to reproduce the measurement.

K2-24 b · TESS · transit timing · Sector 91 · public astronomical data · forecast test · reproducible measurement