Couldn't find element LayerAd

Error finding content

What Causes the Seasons? - Windows to the Universe

Shop Windows to the Universe

The Universe at Your Fingertips 2.0 DVD from the Astronomical Society of the Pacific is in our online store, filled with Earth and space science resources.
The landscape and weather change greatly during the year in regions that have four distinct seasons.
Click on image for full size
Images Courtesy of Corel

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 the cause of the seasons?

You can imagine that if the seasons were caused by the Earth's orbit, people in the northern hemisphere and people in the southern hemisphere would have the same seasons. For example, if winter occured because the Earth was far away from the Sun, everyplace on the Earth would be cold at the same time.

But this is not what happens! Summer in the northern hemisphere occurs at the same time as winter in the south, and vice-versa. It turns out that the Earth's orbit is nearly perfectly circular, and the difference between its closest point and its furthest point is very small. In fact, the Earth is furthest away from the Sun in June when it is summer in the northern hemisphere.

The Earth is a very special planet in many ways. Just as Earth's unique atmosphere and its distance from the Sun work together to make Earth the right temperature to support life, Earth's orbit and its rotation work together to create the seasons.

Last modified June 26, 2008 by Vanessa Pearce.

Shop Windows to the Universe Science Store!

The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

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

North and South: Opposite Seasons

NASA recently started making images of the entire surface of the Earth every month. There are no clouds in the images. They combine many pictures taken at different times when the weather is clear in different...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 Many Names for the Full Moon

Sometimes, in the fall, you may hear people call a Full Moon the "Harvest Moon". That's because farmers can stay in their fields late, after sunset, harvesting their crops by the bright light of a Full...more

Antarctic Weather

Antarctica, home to the South Pole, is very cold! In fact, Antarctica is colder than even the Arctic! Temperatures as low as -129 degrees F (-89 degrees C) have been recorded, and in the interior, near...more

What are the results of VOCALS?

Scientists must work very hard to understand the data collected in field campaigns like VOCALS. They must review and study it to determine what has been learned. Many model runs will be made and analyzed....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

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

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF