Relating Changes in Cometary Rotation to Activity: Current Status and Applications to Comet C/2012 S1 (ISON)

Abstract

We introduce a parameter, X, to predict the changes in the rotational period of a comet in terms of the rotational period itself, the nuclear radius, and the orbital characteristics. We show that X should be a constant if the bulk densities and shapes of nuclei are nearly identical and the activity patterns are similar for all comets. For four nuclei for which rotational changes are well documented, despite the nearly factor 30 variation observed among the effective active fractions of these comets, X is constant to within a factor two. We present an analysis for the sungrazing comet C/2012 S1 (ISON) to explore what rotational changes it could undergo during the upcoming perihelion passage where its perihelion distance will be ~2.7 solar radii. When close to the sun, barring a catastrophic disruption of the nucleus, the activity of ISON will be sufficiently strong to put the nucleus into a non-principal-axis rotational state and observable changes to the rotational period should also occur. Additional causes for rotational state changes near perihelion for ISON are tidal torques caused by the sun and the significant mass loss due to a number of mechanisms resulting in alterations to the moments of inertia of the nucleus.

14 pages, 1 figure

References in corpus (2)

• The Dust Tail of Asteroid (3200) Phaethon
• Properties of Near-Sun Asteroids

Cited by in corpus (26)

• APO Time Resolved Color Photometry of Highly-Elongated Interstellar Object 1I/'Oumuamua
• The tumbling rotational state of 1I/`Oumuamua
• Rotation of Cometary Nuclei: New Lightcurves and an Update of the Ensemble Properties of Jupiter-Family Comets
• Dynamic Sublimation Pressure and the Catastrophic Breakup of Comet ISON
• A rapid decrease in the rotation rate of comet 41P/Tuttle-Giacobini-Kresák
• The Formation of Striae within Cometary Dust Tails by a Sublimation-Driven YORP-like Effect
• Monitoring of the activity and composition of comets 41P/Tuttle-Giacobini-Kresak and 45P/Honda-Mrkos-Pajdusakova
• Characterizing the Dust Coma of Comet C/2012 S1 (ISON) at 4.15 AU from the Sun
• The Sublimative Torques of Jupiter Family Comets and Mass Wasting Events on Their Nuclei
• Will Comet ISON (C/2012 S1) Survive Perihelion?
• The Nucleus of Main-Belt Comet P/2010 R2 (La Sagra)
• Observations of Comet ISON (C/2012 S1) from Lowell Observatory
• Systematics and Consequences of Comet Nucleus Outgassing Torques
• Constraints on the Spin-Pole Orientation, Jet Morphology and Rotation of Interstellar Comet 2I/Borisov with Deep HST Imaging
• Implications of the Small Spin Changes Measured for Large Jupiter-Family Comet Nuclei
• The Unusual Apparition of Comet 252P/2000 G1 (LINEAR) and Comparison with Comet P/2016 BA14 (PanSTARRS)
• The Rotation and Other Properties of Comet 49P/Arend-Rigaux, 1984 - 2012
• Gas Jet Morphology and the Very Rapidly Increasing Rotation Period of Comet 41P/Tuttle-Giacobini-Kresak
• Further investigation of changes in cometary rotation
• Gone in a Blaze of Glory: the Demise of Comet C/2015 D1 (SOHO)
• Meteor Showers on Earth from Sungrazing Comets
• Disintegrating In-Bound Long-Period Comet C/2019 J2
• Results from the Worldwide Coma Morphology Campaign for Comet ISON (C/2012 S1)
• Characterizing the nucleus of comet 162P/Siding Spring using ground-based photometry
• Rotation dynamics and torque efficiency of cometary nuclei
• Predictions for Sparse Photometry of Jupiter-Family Comet Nuclei in the LSST Era