باب:جاپان/Selected article/4

Comet Hyakutake is a دم دار سیارے discovered on January 30, 1996, which passed very close to زمین in March of that year. It was dubbed The Great Comet of 1996; its passage near the Earth was one of the closest cometary approaches of the previous 200 years. Hyakutake appeared very bright in the night sky and was widely seen around the world. The comet temporarily upstaged the much anticipated Comet Hale-Bopp, which was approaching the inner solar system at the time. Scientific observations of the comet led to several discoveries. Most surprising to cometary scientists was the first discovery of ایکس شعاع emission from a comet, believed to have been caused by ionised solar wind particles interacting with neutral atoms in the coma of the comet. The Ulysses spacecraft unexpectedly crossed the comet's tail at a distance of more than 500 million km from the nucleus, showing that Hyakutake had the longest tail known for a comet. Hyakutake is a long-period comet. Before its most recent passage through the solar system, its orbital period was about 17,000 years, but the gravitational influence of the giant planets has increased this period to 100,000 years. The comet was discovered on January 30, 1996, by Yuji Hyakutake an amateur astronomer from southern جاپان. He had been searching for comets for years and had moved to کاگوشیما پریفیکچر partly for the dark skies in nearby rural areas. He was using a powerful set of binoculars with six-inch (152 mm) objective lenses to scan the skies on the night of the discovery.