Bibcode
Shulman, L. M.; Kidger, M.; Serrat-Ricart, M.; Torres-Chico, R.
Referencia bibliográfica
Earth, Moon, and Planets, v. 90, Issue 1, p. 109-117 (2002).
Advertised on:
3
2002
Número de citas
0
Número de citas referidas
0
Descripción
At the First International Conference on Comet Hale-Bopp (Canaries,
1998) many astronomers agreed with the value of the period of axial
rotation of its nucleus, which was obtained by observers by a comparison
of the two sequential patterns of the dust arcs. It was noted that the
pattern had been repeated each ~12 hours. The value 11.35 h
was taken as the period of axial rotation. However, alternative periods
of 4 and 8 days have also been suggested. The possible reasons for this
discrepancy are discussed. It is shown that a short period could be
obtained by a misidentification of the same arc on two sequential images
and, as a result, an overestimate of the radial velocity of dust in the
arcs. To obtain the half day period one must take the projected velocity
of the arc ~ 1.6 km/s, which exceeds the H2O gas expansion
velocity. If one takes a lower expansion velocity a longer period would
be obtained.