Morphology and Evolution of the Spiral Jets Observed in the Inner Coma of Comet Hale-Bopp (1995 O1): the 1995 Teide Observing Campaign

Kidger, M. R.; Serra-Ricart, M.; Bellot Rubio, L.; Torres-Chico, R.; Casas, R.; Chinarro, L. M.; Gomez, A.; Lopez, S.; Manade, L.; Shulman, L.
Bibliographical reference

American Astronomical Society, 187th AAS Meeting, #42.10; Bulletin of the American Astronomical Society, Vol. 27, p.1338

Advertised on:
12
1995
Number of authors
10
IAC number of authors
8
Citations
1
Refereed citations
1
Description
CCD monitoring of Comet Hale-Bopp (1995 O1) has been carried out on more than 50 nights using the 82cm IAC-80 Telescope at Teide Observatory (Tenerife, Spain), operated by the Instituto de Astrofísica de Canarias. A combination of deep exposures of the extended coma in BVRI (up to 2 hours total exposure in a single filter) and near nucleus imaging has been carried out. Major jets were observed in late August, late September and mid-October which were followed from first detection to complete disappearance. We present a video of the evolution of the different events which shows both similarities and important differences between their morphology and evolution. The August and October events feature a structure with a straight, highly collimated jet of increasing projected length with time and a so-called ``spiral arm" which in all three jets ends in a similar PA, close to the anti-solar direction. These jets we interpret on the basis of various models in an attempt to derive basic parameters such as the rotation and axial inclination, as well as the position of the three sites on the nucleus. There is strong evidence that the three events are caused by different active points on the nucleus, sited at different latitudes. We also present light curves of the comet for different apertures (near-nucleus and total coma) which are linked to the different jet events.