Ultra-Hot Jupiter WASP-12 b Gets Sharper Orbital Predictions from TESS Data

A team of astronomers led by Chinedu Jude Nnaji has refined the orbital and physical details of WASP-12 b, an ultra-hot Jupiter. Using data from NASA's TESS mission, they analysed four transits to improve predictions of when the planet crosses its star. Their findings confirm earlier measurements while offering sharper accuracy for future observations.

WASP-12 b has long drawn attention due to its extreme proximity to its host star. Researchers used TESS photometry to study its transits, extracting mid-transit times and refining the planet's ephemeris—the schedule of its orbits. The updated orbital period and reference epoch now allow more precise forecasts of transit events within TESS's observational window.

The team conducted a geometric analysis to determine the planet's size and transit depth. Their results matched previous studies, reaffirming WASP-12 b's highly inflated radius. An observed-minus-calculated (O-C) test also found no meaningful deviations in transit timing, supporting a stable, linear orbital model.

Accurate transit timings and planetary parameters are essential for atmospheric modelling. While the study highlights TESS's capability to refine exoplanet data, no current TESS research provides further orbital precision for WASP-12 b. As a result, its impact on future observations with instruments like the James Webb Space Telescope remains undetermined.

The refined ephemeris and consistent measurements strengthen the foundation for studying WASP-12 b. Researchers can now plan follow-up observations with greater confidence in predicted transit times. The work also underscores TESS's role in improving exoplanet characterisation through high-precision photometry.