Amazing Space- Fast Facts: Comet Hale-Bopp

Description	Hale-Bopp has a very large nucleus. (Most comet nuclei measure only 1.6 to 3.2 km, or 1-2 miles, in diameter.) It could be seen in the sky for a record 19 months — from May 1996 to November 1997 — and was visible through the bright skies of cities.
Age	About the same age as the Sun: 4.5 billion years
Location	Outer solar system — Oort Cloud
Avg. distance from the Sun	It has a highly elongated orbit that takes it very close to the Sun and then flings it out into the outer solar system, well past the orbit of Pluto.
Diameter	The diameter of the nucleus has been estimated to be 40-80 km (25-50 miles).
Mass	Not determined
Orbital period around the Sun	2,392 Earth years