The center of our solar system, a rotating mass of burning gases radiating energy is called the sun. Every second it converts millions of tons of matter into energy, and it has been doing this for some five billion years. Its surface temperature is about 10,000 degrees Fahrenheit, and it is in a constant state of agitation, emitting eruptions of burning gas to distances sometimes as much as hundreds of thousands of miles, before they fall back to the surface.
A solar phenomenon of great interest is the sun spot, which appears dark on the surface of the sun. Sun spots are masses of comparatively cooler gas, sometimes 50,000 miles in diameter.
Magnetic storms on the earth, which interfere with the propagation and reception of radio signals, are related to sun spots, which have occurred in eleven-year cycles.
The sun rotates about its axis, but due to its gaseous composition, the rotation is faster near the equator (25 days
The solar system consists of nine known major planets and thousands of planets or asteroids, traveling in elliptical orbits around the sun, only Venus, Mars, Jupiter, and Saturn are normally used in navigation. Mean distances of the planets from the sun range from 67 million miles for Venus, to 886 million miles for Saturn; the periods required for each to complete a revolution around the sun vary from about 225 days for Venus, to 29 1/2 years for Saturn.
Pluto, the most remote of the planets, is about 5 1/2 light hours, or about 3,670 million miles from the sun and takes more than 248 years to complete a revolution.
