Comet Hale-Bopp was a significant and spectacular comet of the late 20th century, known for its brightness and long visibility. Discovered independently by Alan Hale and Thomas Bopp, it provided valuable scientific data and captured public imagination with its impressive display in the sky.

1. 1. Discovery

• • • Discoverers: Comet Hale-Bopp was independently discovered on July 23, 1995, by two amateur astronomers, Alan Hale and Thomas Bopp.
    • Initial Observation: Both Hale and Bopp were observing in different locations, and their discoveries were announced shortly afterward.
      
      

1. 2. Orbital Characteristics

• • • Orbit: Hale-Bopp has a long-period orbit that takes it around the Sun approximately every 2,533 years.
    • Perihelion: Its closest approach to the Sun, known as perihelion, was on April 1, 1997.
    • Aphelion: The farthest point in its orbit from the Sun, or aphelion, is about 1.5 AU (Astronomical Units) beyond Pluto’s orbit.
      
      

1. 3. Appearance

• • • Brightness: Hale-Bopp was exceptionally bright and visible to the naked eye for a record-setting period. Its brightness was due to its large nucleus and abundant icy and dust materials.
    • Coma and Tails: The comet developed a large coma (a cloud of gas and dust surrounding the nucleus) and two prominent tails—one composed of gas and the other of dust. The dust tail was especially long, extending millions of kilometres.
      
      

1. 4. Visibility

Hale-Bopp was visible to the naked eye for much of 1996 and 1997. It reached its peak visibility in early 1997, when it was visible from Earth without the need for telescopes.

1. 5. Scientific Significance

• • • Study of Cometary Composition: Hale-Bopp provided valuable data on the composition and behaviour of comets, including insights into the physical and chemical properties of its nucleus.
    • Comparison with Other Comets: Its prolonged visibility allowed astronomers to study its evolution over an extended period, providing a comparison with other comets.
      
      

1. 6. Notable Facts

• • • Longest Period: Hale-Bopp’s long period and bright appearance made it one of the most notable comets of the 20th century.
    • Cultural Impact: Its visibility and brightness led to widespread public interest and numerous amateur observations.