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With Explore the Planets, investigate the planets, their moons, and understand the processes that shape them. By G. Jeffrey Taylor, Ph.D. See our DVD collection.

Relativity - Time Dilation

This movie explains the concept of "time dilation", which is part of Einstein's theory of relativity.
Image courtesy of Trent Schindler, National Science Foundation.

This movie explains an idea called "time dilation". Time dilation is an important part of Albert Einstein's theory of relativity. Imagine two people who are moving very, very fast relative to each other. Each of them will think that time is passing more slowly for the other person than it is for herself or himself. In other words, they will think the other person's clocks are running more slowly. Pretty strange, huh? That is just one of the very odd things that Einstein's theory of relativity says is true!

(Note: If you cannot see the movie you may need to download the latest QuickTime player.)

Last modified May 29, 2008 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA