1 April 1997

Comet Hale–Bopp is seen passing at perihelion.

Comet Hale-Bopp was one of the most widely observed comets of the 20th century. It was discovered independently by Alan Hale and Thomas Bopp on July 23, 1995. The comet became visible to the naked eye in May 1996, and it remained visible for about 18 months, making it one of the longest-duration naked-eye comets in recorded history.

Discovery: Alan Hale, an amateur astronomer from New Mexico, and Thomas Bopp, an amateur astronomer from Arizona, both discovered the comet on the same day, though they were not working together. This was a rare event in astronomy, as most comets are discovered by professional astronomers using telescopes.

Appearance: Comet Hale-Bopp had a bright, glowing coma (the fuzzy cloud surrounding the comet’s nucleus) and a long, prominent tail. It was visible to the naked eye for an extended period, even in urban areas with significant light pollution.

Orbit: Hale-Bopp is a long-period comet, meaning it has a highly elliptical orbit that takes it far beyond the orbit of Pluto. Its orbit around the Sun takes about 2,500 years.

Scientific Interest: Scientists were particularly interested in studying Comet Hale-Bopp because it was relatively large and active, giving them valuable insights into the composition and behavior of comets. Numerous observations were made using ground-based telescopes, space telescopes, and spacecraft.

Cult Following: Hale-Bopp gained notoriety beyond the scientific community due to a group known as Heaven’s Gate, a religious cult that believed an alien spacecraft was following the comet. In 1997, 39 members of the cult committed mass suicide in the belief that their souls would be transported to the spacecraft.

Legacy: Comet Hale-Bopp remains one of the most famous comets in history, and its passage in 1997 stimulated public interest in astronomy. It also contributed valuable data to our understanding of comets and their role in the solar system.