Symmetric fits to two TESS image apertures give a four-minute decrease in BW Aquarii eclipse spacing from 2021 to 2025

BW Aquarii has known apsidal motion. This study tests its expected change in eclipse spacing with public TESS data from sectors 42 and 92. It provides 14 fitted eclipse times from SPOC images and two fixed apertures. Symmetric profiles give a decrease of 258.2 seconds for a 3 by 3 pixel aperture and 243.5 seconds for a 5 by 5 pixel aperture over 3.710 years. Conditional error estimates are 6.8 and 6.6 seconds. The 14.7 second aperture difference limits the precision. A flux-level timing method, baseline changes, event omission tests, and stricter image-quality cuts retain a decrease near four minutes. Independent injected profiles test time recovery under the sampled residual noise. The published orbit predicts a decrease of 256.7 seconds, with an approximate error of 38.2 seconds under uniform apsidal motion. QLP light curves give a larger spread across reductions and methods. The image analysis was added after that spread was known. These data support the expected decrease from the known orbit. They do not establish a new companion or a precise new apsidal rate. The package preserves the input files, source records, code, timing tables, figures, and reproduction instructions.

BW Aquarii · TIC 12653017 · TESS · eclipsing binary · eclipse timing · apsidal motion · aperture photometry · reproducible research