TIC 65973133: a small planet candidate transiting a nearby K dwarf in TESS data, including Sector 108

We report a new transiting-planet candidate from the same independent search of TESS light curves of nearby K and M dwarfs that produced TIC 66979777 and TIC 49773023 (DOI 10.5281/zenodo.24040695). The search combines archival sectors with our own photometry of the public full-frame images of Sectors 105–109. TIC 65973133 (K dwarf, 123.9 pc, T = 11.67): P = 16.82564 d, T0 = 2460693.3459 BJD_TDB, depth ~1700 ppm at mid-transit, Rp = 2.90 (+0.54/−0.27) Earth radii, 10 transits with data in Sectors 7, 33, 34, 61, 88 and 108. Without Sector 108 the signal was rejected by our automatic vetting; with it the signal passes (SDE 22.0, SNR 9.2). It passes odd/even, secondary-eclipse, individual-transit, hold-out, stellar-density, pixel-level, Gaia and ephemeris-match tests. TRICERATOPS gives FPP 0.0215 ± 0.0034 and NFPP 0.000 after removing neighbours excluded at pixel level and limiting bound companions with MOLUSC: a likely planet, but it does not reach the statistical-validation threshold (FPP < 0.015). The transit depth differs between sectors more than the errors allow (p = 0.014), so this is the least secure of our three candidates; Sectors 110–111 will test it. Predicted transit times for those sectors are included, published before the data are released. The report, transit photometry, MCMC posteriors, TRICERATOPS and MOLUSC output are attached. Not previously reported in ExoFOP (TOI/CTOI), the NASA Exoplanet Archive or other public candidate lists as of 7 November 2026.