The left panel shows W1-band photometry of 289P in Visit A (MJD 58786: UT 2019 October 30, inbound), phased to the two-peaked period P_rot = 14.8224 ± 2.9899 hr ≈ 15 ± 3 hr. The blue curve displays the fitting result has an amplitude ~ 1.3 mag. The right panel shows spectral analysis curves for the data. The maxima at P_rot = 0.6176 days (=14.8224 hr) is taken as the best solution. The significance level is ~45%.