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Explore a model of Earth's daily rotation.

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This animation shows Earth on an equinox, the first day of spring or fall, when every place on the planet has equal amounts of daylight and dark. It takes 24 hours to make a full rotation.

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A Day on Earth: StudyJams! Science | Scholastic.com

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What causes night and day? This activity will teach students about Earth's rotation and how it impacts our days, nights, and seasons.

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Each year on Earth, we observe patterns of changing temperatures, daylight hours, and seasons. In this activity, you will use a computer simulation to model Earth's orbit around the Sun to help understand why we observe these patterns. Student Book Pages and Student Sheets

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A Day on Earth: StudyJams! Science | Scholastic.com

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What causes night and day? This activity will teach students about Earth's rotation and how it impacts our days, nights, and seasons.

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Ever wondered why the Sun "rises" and "sets" at different times? And why the days are longer in Summer? Watch this animation carefully and you will discover why:

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What Makes Seasons? Explore earth's annual cycle month by month.

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Executables (64-bit and 32-bit) for Windows and (64-bit) for Macintosh computers are available for all of our older projects (NAAP, ClassAction, & Ranking Tasks). The appropriate package for your (or your student's) computer system must be downloaded and installed locally. Note that these are actual applications that run in your native OS and their longevity depends only upon your OS.

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US Dept of Commerce National Oceanic and Atmospheric Administration National Weather Service Sioux Falls, SD 26 Weather Lane Sioux Falls, SD 57104-0198 605-330-4247 Comments? Questions? Please Contact Us.

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During the year, the seasons change depending on the amount of sunlight reaching the Earth as it revolves around the Sun.

The seasons are caused as the Earth, tilted on its axis, travels in a loop around the Sun each year. Summer happens in the hemisphere tilted towards the Sun, and winter happens in the hemisphere tilted away from the Sun. As the Earth travels around the Sun, the hemisphere that is tilted towards or away from the Sun changes.

The hemisphere that is tilted towards the Sun is warmer because sunlight travels more directly to the Earth's surface so less gets scattered in the atmosphere. That means that when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere. The hemisphere tilted towards the Sun has longer days and shorter nights. That's why days are longer during the summer than during the winter.

In general, the further away from the equator you travel, the cooler summer and winter temperatures become. At the equator there are no seasons because each day the Sun strikes at about the same angle. Every day of the year the equator receives about 12 hours of sunlight. The poles remain cool because they are never tilted in a direct path of sunlight. Much light is scattered by the atmosphere before reaching the Earth surface at the poles. During midwinter, when a pole is tilted away from the Sun, there is no daylight at all. The sun never rises! However, during the summer, a pole receives sunlight all the time and there is no night!

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Earth's Tilt Is the Reason for the Seasons!

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During the year, the seasons change depending on the amount of sunlight reaching the Earth as it revolves around the Sun. The seasons are caused as the Earth, tilted on its axis, travels in a loop around the Sun each year.

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the Budget Astronomer - The Tilt of the Earth and the Seasons

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The earth's axis is tilted by about 23.5° from vertical. This tilt remains constant as the earth orbits around the sun. As a result, in part of the earth's orbit the northern hemisphere is tipped more towards the sun, and in part of the orbit it is tipped away from the sun.

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Explore a model of Earth's yearly revolution around the sun.

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In order to illustrate how much sunlight different parts of Earth receive through the year, this model shows our planet much larger and closer to the sun than it actually is. Examine the model carefully to compare the amount of sunlight the Northern and Southern Hemispheres receive in March, June, September, and December.

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The Earth's Orbit - Windows to the Universe

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Windows to the Universe, at http://windows2universe.org/ from the National Earth Science Teachers Association (NESTA). The Website was developed in part with the support of UCAR and NCAR, where it resided from 2000 - 2010. © 2012 National Earth Science Teachers Association. Windows to the Universe® is a registered trademark of NESTA.

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Phil Plait's Bad Astronomy: Misconceptions

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What Causes the Seasons? - Windows to the Universe

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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.