Generous sponsorship of Windows to the Universe is provided by the Hewlett Foundation, the American Geological Institute, the American Geophysical Union, the National Science Foundation, NASA, NCAR, and the CISM and CMMAP projects. NASA CMMAP AGU CISM NCAR Hewlett AGI NSF
The Earth with its Sun.
Click on image for full size
Aris Multimedia Entertainment, Inc. 1994

The Earth's Orbit

Like all planets in our solar system, the Earth is in an elliptical orbit around our Sun. In Earth's case, its orbit is nearly circular, so that the difference between Earth's farthest point from the Sun and its closest point is very small. Earth's orbit defines a two-dimensional plane which we call the ecliptic.

It takes roughly 365 days for the Earth to go around the Sun once. This means that the Earth is rushing through space around the Sun at a rate of about 67,000 miles per hour! The time it takes for the Earth to go around the Sun one full time is what we call a year.

The combined effect of the Earth's orbital motion and the tilt of its rotation axis result in the seasons.

News Flash!
Please take our short survey and let us know what you think of our new website design!
The American Geophysical Union has become a Founding Partner of the Windows to the Universe Project!
Free 2009 Earth Science Kits on Climate Change available for Windows to the Universe Educator Members - Join today!
Up to five free telescopes available to Windows to the Universe Educator Members - Join today!

You might also be interested in:

What Causes the Seasons?

Let's get rid of some common misconceptions about the seasons. The Earth's orbit is in the shape of an ellipse, so that sometimes the Earth is a little bit closer to the Sun than at other times. Is this...more

What is the distance from the Earth to the Sun when the Earth is at perihelion and when it is at aphelion? At what month is the Earth closest to the Sun? What is the circumference of the Earth? How fast is the Earth moving about its axis; how about around the Sun?

If a body (like the Earth) is orbiting around the Sun, we say it is closest to the Sun at perihelion and farthest from the Sun at aphelion. In 2000, perihelion for the Earth was on January 3, 2000, and...more

Starting Points for Science

Some ideas are used in many, many places throughout science. We have grouped these "starting points for science" into three clusters: space, time, and matter. "Space" is the word we use for everything...more

Native American Astronomy

People from Asia crossed the Bering Strait into North America. These people were first in this new land and so they are known as Native Americans. Over time, these people broke into tribes (as seen on...more

Archeoastronomy

"The movements of the heavenly bodies are an admirable thing, well known and manifest to all peoples. There are no people, no matter how barbaric and primitive, that do not raise up their eyes, take note,...more

The Stones of Carnac

The stones of Carnac, France, are probably the most famous stones markings outside of those found at Stonehenge in England. There are many, many stones at Carnac. And these stones are very old too, the...more

The Cairns of Clava

Not too far from Loch Ness, there lies three giant tombs made of stones. They are called the Balnuaran of Clava. The Balnuaran of Clava, giant tombs encased in stone, can be found close to Inverness in...more

Cuzco

Cuzco is located in Southern Peru. It is the ancient capital of the Inca Empire. It is the oldest, continuously occupied city in the Americas. In ancient times, Cuzco was the ceremonial capital and hub...more

Shop Windows to the Universe

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!

Please log in

Username:

Password:

Become a member