Applied geometric trajectory similarity (STTS) to 39.9M TLE records across the full Starlink constellation. Instead of propagating orbits forward through atmospheric models, the framework asks: does this satellite's trajectory geometrically resemble trajectories that preceded confirmed reentries?

Results on 257 confirmed reentries: V1=250.6x basin separation, Recall=1.000, mean detection lead 471 days.

Applied to 15,170 operational satellites: 108 fire the reentry signal. Not in the deorbit campaign. BSTAR is normal — signal is trajectory geometry. 23 are above 600km where drag is negligible.

Prior work (Oliveira et al. 2025, Frontiers) tracked SC25 effects on satellites that already reentered. This asks the forward-looking question: which operational satellites currently show precursor geometry?

Code runs on a clean clone. Reproducible 10/10. https://github.com/mojoatomic/stts.git