Characterizing Sparse Asteroid Light Curves with Gaussian Processes

The Astronomical Journal, vol. 163, pp. 29

Abstract

Abstract In the era of wide-field surveys like the Zwicky Transient Facility and the Rubin Observatory’s Legacy Survey of Space and Time, sparse photometric measurements constitute an increasing percentage of asteroid observations, particularly for asteroids newly discovered in these large surveys. Follow-up observations to supplement these sparse data may be prohibitively expensive in many cases, so to overcome these sampling limitations, we introduce a flexible model based on Gaussian processes to enable Bayesian parameter inference of asteroid time-series data. This model is designed to be flexible and extensible, and can model multiple asteroid properties such as the rotation period, light-curve amplitude, changing pulse profile, and magnitude changes due to the phase-angle evolution at the same time. Here, we focus on the inference of rotation periods. Based on both simulated light curves and real observations from the Zwicky Transient Facility, we show that the new model reliably infers rotational periods from sparsely sampled light curves and generally provides well-constrained posterior probability densities for the model parameters. We propose this framework as an intermediate method between fast but very limited-period detection algorithms and much more comprehensive but computationally expensive shape-modeling based on ray-tracing codes.

Authors 14

1. Christina W. Lindberg

   Johns Hopkins University

   Affiliation as printed

   JHU, 3400 North Charles St., 473 Bloomberg Center for Physics and Astronomy, Baltimore, MD 21218, USA; clindbe2@jhu.edu

   JHU, 3400 North Charles St., 473 Bloomberg Center for Physics and Astronomy, Baltimore, MD 21218, USA

2. Daniela Huppenkothen Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands

3. Lynne Jones
   Affiliation as printed

   AerotekSuite 150, 4321 Still Creek Drive, Burnaby, BC V5C6S7, Canada

   Rubin Observatory, 933 N. Cherry Avenue, Tucson, AZ 85719, USA

4. Bryce Bolin

   California Institute of Technology · Infrared Processing and Analysis Center

   Affiliation as printed

   Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA

   IPAC, Mail Code 100-22, Caltech, 1200 E. California Boulevard, Pasadena, CA 91125, USA

5. Mario Jurić

   University of Washington

   Affiliation as printed

   DIRAC Institute, Department of Astronomy, University of Washington, 3910 15th Avenue NE, Seattle, WA 98195, USA

   Department of Astronomy, University of Washington, 3910 15th Avenue NE, Seattle, WA 98195, USA

6. Vahid Zachary Golkhou

   University of Washington

   Affiliation as printed

   DIRAC Institute, Department of Astronomy, University of Washington, 3910 15th Avenue NE, Seattle, WA 98195, USA

7. Eric C. Bellm

   University of Washington

   Affiliation as printed

   DIRAC Institute, Department of Astronomy, University of Washington, 3910 15th Avenue NE, Seattle, WA 98195, USA

8. Andrew J Drake

   California Institute of Technology

   Affiliation as printed

   Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA

9. M. J. Graham

   California Institute of Technology

   Affiliation as printed

   California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA

10. Russ R. Laher

    California Institute of Technology · Infrared Processing and Analysis Center

    Affiliation as printed

    IPAC, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA

11. Ashish A. Mahabal

    California Institute of Technology

    Affiliation as printed

    Center for Data-driven Discovery, California Institute of Technology, Pasadena, CA 91125, USA

    Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA

12. Frank J. Masci

    California Institute of Technology · Infrared Processing and Analysis Center

    Affiliation as printed

    IPAC, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA

13. Reed Riddle

    California Institute of Technology

    Affiliation as printed

    California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA

14. Kyung Min Shin

    California Institute of Technology

    Affiliation as printed

    California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA