Comet Hale–Bopp is a comet that was perhaps the most widely observed of the 20th century, and one of the brightest seen for many decades. Hale–Bopp was discovered on July 23, 1995, separately by Alan Hale and Thomas Bopp prior to it becoming naked-eye visible on Earth.

Orbital period: 2,533 years

Predicted next perihelion: 4380

Radius: 19 mi

Orbits: Sun

Discoverers: Thomas Bopp, Alan Hale

Did you know: Astronomers have estimated Hale-Bopp's nucleus to be 19-25 miles (30-40 kilometers) in diameter.