The Reason for the Seasons. Preschool Crafts for Kids*: Easy Sundial Paper Plate Craft. The Sun l Sun Facts and images. Our Sun is a normal main-sequence G2 star, one of more than 100 billion stars in our galaxy. diameter: 1,390,000 km. mass: 1.989e30 kgtemperature: 5800 K (surface) 15,600,000 K (core) History of The Sun The Sun is by far the largest object in the solar system. It contains more than 99.8% of the total mass of the Solar System (Jupiter contains most of the rest). It is often said that the Sun is an "ordinary" star. The Sun is personified in many mythologies: the Greeks called it Helios and the Romans called it Sol. The Sun is, at present, about 70% hydrogen and 28% helium by mass everything else ("metals") amounts to less than 2%. The outer layers of the Sun exhibit differential rotation: at the equator the surface rotates once every 25.4 days; near the poles it's as much as 36 days.
Conditions at the Sun's core (approximately the inner 25% of its radius) are extreme. The Sun's power (about 386 billion billion mega Watts) is produced by nuclear fusion reactions. The Sun's satellites. Interactive 3D model of Solar System Planets and Night Sky. Scale of Universe - Interactive Scale of the Universe Tool. EarthCam - Webcam Network.