Heliocentric Dependence of Sodium Emission of Comet Hale-Bopp (C/1995O1)
Sodium Emission in Cometary Comae
The Morphological Change of the Sodium Tail in Comet Hale-Bopp (C/1995 O1)
Comet C/1995 O1 (Hale-Bopp)
Comet C/1995 O1 (Hale-Bopp)