The Rotation Period of C/1995 01 (Hale-Bopp)

Licandro, Javier; Bellot Rubio, Luis R.; Boehnhardt, Hermann; Casas, Ricard; Goetz, Benedikt; Gomez, Angel; Jorda, Laurent; Kidger, M. R.; Osip, David; Sabalisck, Nanci; Santos, Pablo; Serr-Ricart, Miquel; Tozzi, Gian Paolo; West, Richard
Bibliographical reference

Astrophysical Journal Letters v.501, p.L221

Advertised on:
7
1998
Number of authors
14
IAC number of authors
1
Citations
30
Refereed citations
28
Description
C/1995 O1 (Hale-Bopp) was observed in daylight on 16 days between 1997 April 1 and 1997 April 28, five of which had long time sequences (up to 10 hr of data), using the near infrared CAIN camera on the 1.5 m Carlos Sanchez Telescope at Teide Observatory (Tenerife, Canary Islands, Spain). Three spiral dust jet structures were observed for several almost complete rotations. A nucleus rotation period of 11.34+/-0.02 hr was determined from two different methods. No variations of the rotation period with time due to precessional effects were found in our data. However, the time sampling of the observations, similar to the suggested spin precession period, prevents us from ascertaining whether such variations exist. We note, though, that the good agreement of our results with the rotation periods at different epochs reported by other groups suggests that if they exist, these variations must be small, hence the rotation cannot be very complex.