Comet ISON Visualizations

Comet ISON approaches the inner solar system having just passed the orbit of Jupiter. It passes very close to Mars in early October 2013 before dipping below the ecliptic on its way towards perihelion on November 28, 2013. Comet ISON will make its closest pass to the Earth in January 2014 when it should be visible in the northern hemisphere.In these movies, the cameras chase the comet from two different points of view. ||

Currently located beyond the orbit of Jupiter, Comet ISON is heading for a very close encounter with the sun next year. In November 2013, it will pass less than 0.012 Astronomical Units (Wikipedia) (1.8 million kilometers) from the center of the Sun, 1.2 million kilometers from the solar surface. The fierce heating it experiences in that approach could turn the comet into a bright naked-eye object.NOTE: This visualization was revised in March 2013 to fix an ephemeris error. Other enhancements were included in the revision. Also fixed an error where perihelion distance was mistakenly labeled as distance from solar surface. ||

Comet C/2012 S1, better known as comet ISON, may become a dazzling sight as it traverses the inner solar system in late 2013. During the weeks before its Nov. 28 close approach to the sun, the comet will be observable with small telescopes, and binoculars. Observatories around the world and in space will track the comet during its fiery trek around the sun. If ISON survives its searing solar passage, which seems likely but is not certain, the comet may be visible to the unaided eye in the pre-dawn sky during December.Watch the animations on this page to visualize ISON's voyage through the inner solar system, or build the paper model of its orbit to track the changing positions of Earth and the comet.Like all comets, ISON is a clump of frozen gases mixed with dust. Often described as "dirty snowballs," comets emit gas and dust whenever they venture near enough to the sun that the icy material transforms from a solid to gas, a process called sublimation. Jets powered by sublimating ice also release dust, which reflects sunlight and brightens the comet. On Nov. 28, ISON will make a sweltering passage around the sun. The comet will approach within about 730,000 miles (1.2 million km) of its visible surface, which classifies ISON as a sungrazing comet. In late November, its icy material will furiously sublimate and release torrents of dust as the surface erodes under the sun's fierce heat, all as sun-monitoring satellites look on. Around this time, the comet may become bright enough to glimpse just by holding up a hand to block the sun's glare.Sungrazing comets often shed large fragments or even completely disrupt following close encounters with the sun, but for ISON neither fate is a forgone conclusion.Following ISON's solar swingby, the comet will depart the sun and move toward Earth, appearing in morning twilight through December. The comet will swing past Earth on Dec. 26, approaching within 39.9 million miles (64.2 million km) or about 167 times farther than the moon.The comet was discovered on Sept 21, 2012, by Russian astronomers Vitali Nevski and Artyom Novichonok using a telescope of the International Scientific Optical Network (ISON) located near Kislovodsk.Learn more about sungrazing comets. ||