The Ulysses Comet Watch

The Ulysses Comet Watch Network has as its main goal to gather cometary data during times of polar passage by the Ulysses spacecraft. If successful, the comets studied could be used as indicators of high-latitude solar winds.

The Network was modeled after the very successful International Halley Watch observation networks, which operated during 1985 and 1986 gathering thousands of Halley images. For the Ulysses Comet Watch, two components were proposed: a bright comet network of both amateurs and professionals, doing work similar to the Halley watch effort; and a faint comet group consisting of professional observatories and technically advanced amateurs.

The Network was established in late 1992, and a request for participation was published in Sky & Telescope magazine. To date, more than 250 observers from around the world have volunteered for the network. Currently, they are kept informed of upcoming comets through two vehicles: the Ulysses Comet Watch Newsletter (of which ten have been sent to date), and via an E-mail distribution list. This Website is the latest addition to the Ulysses Comet Watch outreach efforts.

The Network's approach has been to gather data on appropriate comets, with an eye toward eventual data reduction and correlation with relevant Ulysses data, and finally publication.

Because of the unique orbit Ulysses is following, several important criteria have been established for network observations. First, bright comets (total magnitude greater than 6) are most desirable. Second, the major observation periods are limited to times when a comet is with 2 AU of the sun and 20 degrees latitude of the spacecraft.

The following comets have been observed by the network: Borrelly, D'Arrest, Encke, Honda-Mrkos-Padjuakova, Mueller, Pons-Winnecke, Tempel 2, Tuttle, Tuttle-Giacobini-Kresak, Hyakutake, and de Vico. The comet under observation now is Hale-Bopp, although we are asking observers to try for the difficult-to-observe Machholz 1. Observers have sent in more than 200 observations since the network was formed.

Join the Ulysses Comet Watch.

Comet Images from Watch Members.

Links to other Comet Pages.