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Title: An asymmetric outgassing model for cometary nongravitational accelerations

Journal Article · · Astronomical Journal; (USA)
DOI:https://doi.org/10.1086/115198· OSTI ID:5250492
;  [1]
  1. California Institute of Technology, Pasadena (USA)

The standard nongravitation force model has been modified by allowing the water-vaproization curve to peak a certain number of days (DT) either before or after perihelion, and the modification is shown to often improve the data fit. The best fit to the astrometric data is generally achieved for a value of DT corresponding to the offset in the comet's visual light curve. The asymmetric model, which more accurately mimics the comet's outgassing history, suggests only weakly that the rotation direction of Comet Halley is direct, and it does not provide evidence that the rotation axis of Comet Kopff passed through its orbit plane in the early twentieth century. Approximate lag angles of 4 deg for Comet Halley and 10 deg for Comet d'Arrest are found using the asymmetric model, and it is noted that these values are lower than those obtained with the standard model. 34 refs.

OSTI ID:
5250492
Journal Information:
Astronomical Journal; (USA), Vol. 98; ISSN 0004-6256
Country of Publication:
United States
Language:
English