HaleBopp

Hale-Bopp, designated C/1995 O1, is a long-period comet that was independently discovered in 1995 by amateur astronomers Alan Hale in New Mexico and Thomas Bopp in Arizona. The object was reported in July 1995, and the comet was named in their honor.

From the outer reaches of the Solar System, Hale-Bopp followed a highly elongated orbit and reached perihelion on approximately March 1997 at a distance of about 0.9 astronomical units from the Sun. The nucleus is estimated to be tens of kilometers across, surrounded by a vast coma, and it developed both a prominent dust tail and a blue ion tail that extended for millions of kilometers.

In the years surrounding perihelion, Hale-Bopp became unusually bright, reaching naked-eye visibility at magnitudes around −1 to −2 and remaining visible to the naked eye for about 18 months. It was extensively observed by professional and amateur astronomers worldwide, yielding valuable data on cometary composition and activity, including emissions from gases such as CN and C2.

The comet’s long visibility and striking appearance captured widespread public attention. It remains one of the most widely observed comets of the modern era. Hale-Bopp also intersected wider cultural discussions, notably being connected in media coverage to the Heaven’s Gate cult, whose members died in 1997; the event occurred independently of the comet but coincided in time with its prominence.