The trans-Neptunian object (84922) 2003 VS2 through stellar occultations

Abstract

We present results from three world-wide campaigns that resulted in the detections of two single-chord and one multi-chord stellar occultations by the Plutino object (84922) 2003~VS${}_2$. From the single-chord occultations in 2013 and 2014 we obtained accurate astrometric positions for the object, while from the multi-chord occultation on November 7th, 2014, we obtained the parameters of the best-fitting ellipse to the limb of the body at the time of occultation. We also obtained short-term photometry data for the body in order to derive its rotational phase during the occultation. The rotational light curve present a peak-to-peak amplitude of 0.141 $\pm$ 0.009 mag. This allows us to reconstruct the three-dimensional shape of the body, with principal semi-axes $a=313.8\pm 7.1$ km, $b=265.5_{-9.8}^{+8.8}$ km, and $c=247.3_{-43.6}^{+26.6}$ km, which is not consistent with a Jacobi triaxial equilibrium figure. The derived spherical volume equivalent diameter of $548.3_{-44.6}^{+29.5}$ km is about 5\% larger than the radiometric diameter of 2003~VS${}_2$ derived from Herschel data of $523\pm 35$ km, but still compatible with it within error bars. From those results we can also derive the geometric albedo ($0.123_{-0.014}^{+0.015}$) and, under the assumption that the object is a Maclaurin spheroid, the density $\rho =1400_{-300}^{+1000}$ for the plutino. The disappearances and reappearances of the star during the occultations do not show any compelling evidence for a global atmosphere considering a pressure upper limit of about 1 microbar for a pure nitrogen atmosphere, nor secondary features (e.g. rings or satellite) around the main body.

arXiv comment22 pages, 14 figures, 1 appendix

References in corpus (32)

• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• The Pluto system: Initial results from its exploration by New Horizons
• A ring system detected around the Centaur (10199) Chariklo
• The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation
• "TNOs are Cool": A survey of the trans-Neptunian region X. Analysis of classical Kuiper belt objects from Herschel and Spitzer observations
• Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt Object
• Predicting Stellar Angular Sizes
• Densities of Solar System Objects from their Rotational Lightcurves
• Possible ring material around centaur (2060) Chiron
• An Outer Planet Beyond Pluto and Origin of the Trans-Neptunian Belt Architecture
• Colors and taxonomy of Centaurs and Trans-Neptunian Objects
• TNOs are Cool: A survey of the trans-Neptunian region V. Physical characterization of 18 Plutinos using Herschel PACS observations
• Short-term variability of a sample of 29 trans-Neptunian objects and Centaurs
• Size and shape of Chariklo from multi-epoch stellar occultations
• Light Curves of Dwarf Plutonian Planets and other Large Kuiper Belt Objects: Their Rotations, Phase Functions and Absolute Magnitudes
• Study of the plutino object (208996) 2003 AZ84 from stellar occultations: size, shape and topographic features
• Contrast sensitivities in the Gaia Data Release 2
• ALMA Discovery of Dust Belts Around Proxima Centauri
• The Intrinsic Neptune Trojan Orbit Distribution: Implications for the Primordial Disk and Planet Migration
• The structure of Chariklo's rings from stellar occultations
• Results from the 2014 November 15th multi-chord stellar occultation by the TNO (229762) 2007 UK${}_{126}$
• Candidate stellar occultations by large trans-neptunian objects up to 2015
• Coordinated thermal and optical observations of Trans-Neptunian object (20000) Varuna from Sierra Nevada
• Absolute magnitudes and phase coefficients of trans-Neptunian objects
• Physical properties of centaur (54598) Bienor from photometry
• A mid-term astrometric and photometric study of Trans-Neptunian Object (90482) Orcus
• JWST observations of stellar occultations by solar system bodies and rings
• TNOs are Cool: a survey of the Transneptunian Region XII. Thermal light curves of Haumea, 2003 VS2 and 2003 AZ84 with Herschel Space Observatory-PACS
• The future of stellar occultations by distant solar system bodies: perspectives from the Gaia astrometry and the deep sky surveys
• 2008 OG${}_{19}$: A highly elongated Trans-Neptunian Object

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