Star Proper Motions Based on Two-epoch Observations from the SDSS and DESI Imaging Surveys
Year: 2025
Type: article
Abstract: In this study, we present the construction of a new proper-motion catalog utilizing the photometric data from the Sloan Digital Sky Survey (SDSS) and Dark Energy Spectroscopic Instrument (DESI) imaging surveys, with a median time baseline of about 13 yr. To mitigate systematic errors, the DESI galaxy positions are employed to establish a reference frame and to correct the position-, magnitude-, and color-dependent discrepancies between the SDSS and DESI imaging data sets. Spanning 12,589 deg2, the catalog encompasses about 223.7 million non-Gaia objects down to m r ∼ 23. Based on 734,000 quasars, the assessment of the global systematic errors in the DESI−SDSS proper-motion catalog yields values of 0.06 mas yr−1 for μ α * and 0.12 mas yr−1 for μ δ . The catalog exhibits precision surpassing 3.4 mas yr−1, albeit varying with position, color, and magnitude. An additional evaluation employing approximately 2644 distant star samples yields an overall precision of approximately 2.5 and 2.9 mas yr−1 for μ α * and μ δ , respectively. Further comparisons with proper motions from SDSS Stripe 82 reveal a strong consistency between the two data sets. As a practical application, we utilize fainter non-Gaia objects in our catalog to update the proper motions of 15 star clusters. The resulting proper motions for these clusters exhibit excellent consistency with those derived from Gaia data. Our proper-motion measurements, characterized by a deeper limiting magnitude, stand as a valuable complement to the Gaia data set.
Source: The Astronomical Journal
Authors: Yun-Ao Xiao, Hu Zou, Xin Xu, Lu Feng, Wei-Jian Guo, Wen-Xiong Li, Shu-Fei Liu, Zhi-Xia Shen, Gaurav Singh, Ji-Peng Sui, Jia-Li Wang, Sui-Jian Xue
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, Alfred P. Sloan Foundation, Yale University, Vanderbilt University, Princeton University, Ohio State University, California Institute of Technology, Harvard University, University of Washington, Johns Hopkins University, Carnegie Mellon University, University of Portsmouth, New Mexico State University, European Space Agency, York University, National Natural Science Foundation of China, Chinese Academy of Sciences, Office of Science, Jet Propulsion Laboratory, College of Engineering, Michigan State University, Division of Astronomical Sciences, High Energy Physics, Brookhaven National Laboratory, Lawrence Berkeley National Laboratory
OpenAlex ID: W4408205182