Since the beginning of 1995, there has been explosive growth of the number of home pages dealing with comets. Comet Hale-Bopp has only increased this growth. The goal here is not to provide every possible link to every comet-related home page. I believe that the links given below are a good sampling of what is available. In some cases, I have linked to excellent lists of links. You should be able to find whatever comet page you are looking for through these links.
For rapid notification of comet (and other astronomical) discoveries, it is always best to go to the source: CBAT. CBAT issues the IAU Circulars (IAUCs) and runs an on-line computer service. There is lots of information, free of charge, on comets and minor planets. Other services are provided to subscribers only, but information about the services can be obtained via this link. (You can also get information about the Minor Planet Center (MPC)). If you are a serious comet observer, this is your most important source of information.
The archive for visual comet observations for the past 16 years has been the ICQ. The Comet Handbook, put out annually by the ICQ, provides ephemeridies for known (periodic) comets.
The Jet Propulsion Laboratory (JPL) has three images of 1P/Halley that illustrate different types of tail structure.
Bill Arnett, as part of his The Nine Planets, has a nice page of general information on comets including some images of major comets. There are also links to other comet pages.
Another excellent source of general information is the comets section from Views of the Solar System
Gary Kronk is the author "Comets, A Descriptive Catalog" (Enslow Publishers, 1984). His Comet Page provides excellent background information on comets. There are also position plots for various comets. He also maintains an excellent page on meteors.
The Astronomer is one of the best publications for the active observer. This monthly publication, which has been around since 1965, has now come to the Web. Not only are comets covered, other objects of observational interest to the amateur astronomer are also discussed.
Also from the UK, we get the BAA Comet Section Home Page, which includes some excellent information on observing comets.
Ron Baalke (JPL) maintains a comprehensive list of links to other Hale-Bopp Pages.
Charles Boley's Comets On-Line has an excellent summary of what is available. He also has lots of stuff on weather, etc (if you go up to his main home page).
Patrick Vanouplines has put together this page with useful information on 95P/Chiron = Asteroid 2060.
Stardust is planning a flyby of the comet 81P/Wild 2 and collect cometary dust to be returned to the Earth. This page provides details of the mission and links to other comet related pages.
The JPL Shoemaker-Levy Collision with Jupiter Home Page has excellent pictures and links to the other SL9 home pages. Of course, this impact story is perhaps more about Jupiter than comets...
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