Comet Hale-Bopp is spinning. The nucleus
of the comet is a dirty snowball about 25 miles in diameter
that spins about once every 12 hours.
As Comet Hale-Bopp
spins, parts of the comet's surface shoot away in jets. Ejected
material therefore makes rings, which appear in above photograph
as "hoods"
in the coma. Even though
the central part of Comet Hale-Bopp's
coma is quite condensed, the nucleus is not visible. Comet Hale-Bopp
is now headed south, away from the Sun,
and is getting dimmer.
At its brightest last week, it was even brighter than Comet Hyakutake
was last year, although with a less prominent tail.
Comet Hale-Bopp
will still be easily visible to northern observers for several
weeks in the northwest sky after sunset.
