Earth's Orbit

In astronomy, the Earth's orbit is the motion of the Earth around the Sun, from an average distance of approximately 150 million kilometers away. A complete orbit of the earth around the Sun occurs every 365.256363 mean solar days (1 sidereal year). This motion gives an apparent movement of the Sun with respect to the stars at a rate of about 1°/day (or a Sun or Moon diameter every 12 hours) eastward, as seen from Earth. On average it takes 24 hours—a solar day—for Earth to complete a full rotation about its axis relative to the Sun so that the Sun returns to the meridian. The orbital speed of the Earth around the Sun averages about 30 km/s (108,000 km/h), which is fast enough to cover the planet's diameter (about 12,700 km) in seven minutes, and the distance to the Moon of 384,000 km in four hours.

Viewed from a vantage point above the north poles of both the Sun and the Earth, the Earth would appear to revolve in a counterclockwise direction about the Sun. From the same vantage point both the Earth and the Sun would appear to rotate in a counterclockwise direction about their respective axes.

Read more about Earth's Orbit:  History of Study, Influence On The Earth, Events in The Orbit, Future

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