Astrometry-Oriented Relative Photometry Test of Dwarf Planet Haumea

The 80 cm telescope at Yaoan Station, Purple Mountain Observatory was used to observe the dwarf planet Haumea for two runs from February to April 2022. Interference fringes were removed from all the frames, and the instrument magnitude of Haumea was derived by relative photometry technology. Then, the photometric data were normalized for combining two observation runs to analysis. The rotation period of Haumea was obtained by the PDM (Phase Dispersion Minimization) method and the Lomb-Scargle Periodogram, respectively. The difference between the results by the two methods was 0.072 s, which showed good consistency. Our photometric results reveal a distinct, double-peaked rotational light curve with a period of 3.915 4 ±0.000 2 h and peak-to-peak amplitude of 0.26 ±0.01 mag. Through the derived rotational light curve, it is finally estimated that the maximum influence of the photometric change of Haumea due to rotation on the astrometry is -9~9 mas. The test has a basic significance for future high-precision astrometry.