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Comet Hale-Bopp Reaches Perihelion

On April 1, 1997, the comet Hale-Bopp made its closest approach to the sun at 0.914 AU. Discovered on July 23, 1995, the comet was named after its discoverers, astronomers Alan Hale and Thomas Bopp. Hale discovered the comet while using his telescope in his New Mexico yard. Bopp, on the other hand, discovered the comet with a friend’s telescope while looking at stars in Arizona. Hale alerted the Central Bureau for Astronomical Telegrams of his discovery through email, while Bopp sent a Western Union telegram to the organization. In 1997, Hale-Bopp was one of the brightest objects in the sky and could be seen in the sky with the naked eye for 18 months. The comet was so bright it could even be seen in major cities. The comet was visible all night in the northern hemisphere until its passed perihelion, when it began moving into view in the southern hemisphere. While the last naked-eye sighting occurred in December of 1997, astronomers believe the comet will be detected with large telescopes until 2020. Hale-Bopp is a long period comet. It is believed that its last perihelion occurred around 4,200 years ago. Records from the ancient Egyptians mention a “long hair” star in the pyramid to pharaoh Pepi I (2332-2283BC). Hale-Bopp’s orbit was significantly shortened when it encountered Jupiter’s gravity in 1996. Astronomers now believe that Hale-Bopp has a period of 2,533 with an aphelion of 370 AU. Scientists are optimistic that Hale-Bopp will never collide with Earth, but if a collision did occur, the results would be disastrous. 

 Items in Our Collection

Comet of the Century: from Halley to Hale-Bopp by Fred Schaaf

 Comet Hale-Bopp: find and enjoy the great comet by Robert Burnham

Great Comets by Robert Burnham