Kepler-289 observed-time table:
Greklek-McKeon, M., Knutson, H. A., Vissapragada, S., Jontof-Hutter, D., Chachan, Y., Thorngren, D., and Vasisht, G. (2023), Astronomical Journal 165, 48.
DOI: https://doi.org/10.3847/1538-3881/ac8553
Pinned author version: https://arxiv.org/abs/2208.00022v1
Publisher original MRT: https://content.cld.iop.org/journals/1538-3881/165/2/48/revision1/ajac8553t1_mrt.txt
CC BY 4.0: https://creativecommons.org/licenses/by/4.0/
AAS publication policy: https://journals.aas.org/oa/
Original source table is unchanged. Adapted CSV selects actual observed/error columns, derives per-planet epoch numbers from the global source counter, and retains the original source number. Predicted values are excluded from likelihood input. The missing 2021 observed value remains missing. No author endorsement is implied.

The original arXiv manuscript and publisher MRT say BJD-2454000 / JD-2454000 without declaring UTC versus TDB. The tutorials retain that ambiguity; no time-scale conversion is invented.

Synthetic trajectories and posterior calculations:
Original Sandbox Physics educational calculations, 2026. They are separate from measured Kepler photometry. The reduced two-planet harmonic posterior is conditional on stated priors, diagonal timing errors and fixed 1.08-solar stellar mass. Its residual discrepancy is a material result.

Independent numerical reference:
REBOUND 5.2.2 IAS15, epsilon 1e-12, installed separately under its own GPL license. No REBOUND or GPL TTVFast code is included in the protected browser Engine. The public Python verification wrapper requires a separate optional REBOUND installation.

Original standalone Python scripts in this tutorial:
Copyright (c) 2026 Sandbox Physics. MIT License.
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The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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