Refined rotational period, pole solution, and shape model for (3200) Phaethon

Journal Article · Sat Sep 20 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/793/1/50· OSTI ID:22365022

Ansdell, Megan; Meech, Karen J.; Kaluna, Heather ^[1]; Hainaut, Olivier ^[2]; Buie, Marc W. ^[3]; Bauer, James ^[4]; Dundon, Luke ^[5]

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1. NASA Astrobiology Institute, Honolulu, HI 96822 (United States)
2. European Southern Observatory, Karl Schwarzschild Straße, 85748 Garching bei München (Germany)
3. Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)
4. Jet Propulsion Laboratory, 4800 Oak Grove Drive, MS 183-401, Pasadena, CA 91109 (United States)
5. United States Navy, Washington, DC 20350 (United States)

(3200) Phaethon exhibits both comet- and asteroid-like properties, suggesting it could be a rare transitional object such as a dormant comet or previously volatile-rich asteroid. This justifies detailed study of (3200) Phaethon's physical properties as a better understanding of asteroid-comet transition objects can provide insight into minor body evolution. We therefore acquired time series photometry of (3200) Phaethon over 15 nights from 1994 to 2013, primarily using the Tektronix 2048 × 2048 pixel CCD on the University of Hawaii 2.2 m telescope. We utilized light curve inversion to (1) refine (3200) Phaethon's rotational period to P = 3.6032 ± 0.0008 hr; (2) estimate a rotational pole orientation of λ = +85° ± 13° and β = –20° ± 10°; and (3) derive a shape model. We also used our extensive light curve data set to estimate the slope parameter of (3200) Phaethon's phase curve as G ∼ 0.06, consistent with C-type asteroids. We discuss how this highly oblique pole orientation with a negative ecliptic latitude supports previous evidence for (3200) Phaethon's origin in the inner main asteroid belt as well as the potential for deeply buried volatiles fueling impulsive yet rare cometary outbursts.

• OSTI ID: 22365022
• Journal Information: Astrophysical Journal, Vol. 793, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTEROIDS
CHARGE-COUPLED DEVICES
COMETS
EVOLUTION
PHOTOMETRY
PHYSICAL PROPERTIES
PLANETS
TELESCOPES
VISIBLE RADIATION