Satellites of Comet Hale-Bopp (update)
Reprinted from the Meta Research Bulletin vol. 7, #3, pp. 47-48 (1998)
From a JPL preprint submitted to Earth, Moon & Planets, dated Jan. 1998, by Z. Sekanina, with the bold title, “Detection of a satellite orbiting the nucleus of Comet Hale-Bopp (C/1995O1)”. May-Oct. 1996 images of the comet from Hubble’s WFPC2 instrument show several bright spots quite close to the primary nucleus that change position from picture to picture, but move with the comet, not the star background. The brightest of these has an average signal-to-primary brightness ratio of 0.21 +/- 0.03, suggesting a satellite with diameter 30 km for a main nucleus size of about 70 km. Projected distances from the primary nucleus vary from 160 to 210 km, or 0.06 to 0.10 arcsec. Orbital periods are about 2-3 days, and the orbits appear dynamically stable. The Oct. 1995 Hubble images (the last before May 1996) had sub-pixel separation, and therefore could not have detected even the largest satellite. Ground-based detection of multiple nuclei of such comets is altogether unlikely because of the atmosphere’s effect on the light’s point-spread function. Therefore, the failure to detect these satellites in other images is not inconsistent with this new data.
Our Meta Research web site <http://www.metaresearch.org> predicted Hale-Bopp satellites (as a consequence of the exploded planet hypothesis) well before these Hubble images were taken in 1996. Indeed, the prediction can still be found at the site. We also made this prediction in this Bulletin: "The satellites of Comet Hale-Bopp", MRB 4, 49-51 (1995). Meta Research members may justifiably share in the credit for this success because of their support for the underlying research.
Later relevant publications: Icarus 140, 221-230 (1999); Earth-Moon-Planets, in press (1999).