The Solar System

latest fighterjet F-22 Raptor! Earth spins from the West to East so in relative terms it appears to us that the Sun rises in the East and sets in the West.

The internal axis of Earth's rotation is tilted at 23.5 degrees from perpendicular to the plane of our orbit — a tilt that causes our seasons.


Earth takes approximately 365.25 days to go around the Sun. It covers a distance of about 584 million miles along its orbit in that time. The average orbital velocity of Earth thus works out to 66,500 mph. Did you know the closer a planet is to the Sun the higher is the orbital velocity it requires to keeps itself from falling into it?

The gravitational pull between the Earth and the Sun is such that it exactly balances out with the centripetal force experienced by Earth, else we'll either fly out of the orbit or fall into the Sun. This is called

← Page-20 p.21 Page-22 →