The printed ASASSN-24fw ring size and speed fail the 2024–2025 ZTF test under constant straight motion

We test whether the ring size and speed in Table 5 of Shah et al. (2026) can explain the ASASSN-24fw eclipse. We use public ZTF DR24 data. After quality cuts, 42 deep g measurements span 194.684 days. A separate set of 41 deep r measurements spans 182.697 days. We assume one compact ring system with constant straight motion. The span cannot exceed twice the sum of the ring and stellar radii divided by the speed. The printed median size of 16.71 stellar radii and speed of 1.01 stellar radii per day allow at most 35.069 days. This bound treats the size as a radius, although the source text calls it a diameter. The diameter reading gives 18.525 days. Combining the larger size and lower speed at the printed marginal limits gives only 53.978 days under the radius reading. These are duration bounds, not new light curve fits. Stricter quality cuts and removal of end nights preserve the conflict. At the printed speed, the deep g span requires a ring radius of at least 97.316 stellar radii. The result identifies a conflict between the printed parameters and the data under the stated motion model. We did not inspect the original fitting code. The test does not reject all disk models or determine the companion mass. Earlier work already inferred a larger disk under a circular orbit assumption. We supply the data, image checks, source records, proof, code, and results for inspection and reuse.

ASASSN-24fw · J0705+0612 · ZTF DR24 · circumsecondary disk · occultation · ring geometry · duration bound · reproducible astronomy