Solar System their mass, orbit, and distance from the Sun, with a possibly significant contribution from comets. The Sun, which comprises nearly all the matter in the Solar System, is composed of roughly 98% hydrogen and helium. Jupiter and Saturn, which comprise nearly all the remaining matter, are also primarily composed of hydrogen and helium. A composition gradient exists in the Solar System, created by heat and light pressure from the Sun; those objects closer to the Sun, which are more affected by heat and light pressure, are composed of elements with high melting points. Objects farther from the Sun are composed
Solar eclipses on Jupiter the variations were caused by the varying distance between Earth and Jupiter as the two planets moved in their orbits around the Sun. Spacecraft can be used to observe the solar eclipses on Jupiter; these include "Pioneer 10" and "Pioneer 11" (1973 and 1974), "Voyager 1" and "Voyager 2" (1979), "Galileo" orbiter (1995–2003), "Cassini–Huygens" (2000) and "New Horizons" (2007) observed the transits of their moons and its shadows. The mean angular diameter of the Sun as viewed from Jupiter is 372 arc-seconds, or 6' 12" (about that of the Sun as viewed from Earth), varying slightly from 381" at perihelion