Friday, June 17, 2011

Show the True Shape of Earth's Orbit

CLICK HERE to view the Eccentricity Demonstrator. The shape of Earth's orbit around the Sun is not a perfect circle . . . BUT, it is pretty close. Unfortunately, textbooks often exaggerate the eccentricity of Earth's orbit. Use this online demonstration to let students see the true shape of our orbit, AND allow them to compare it to some of the more elliptical orbits of other objects.

Simply input the eccentricities to see the true orbital shapes. Earth is .02 (rounded), Mercury is .21, Pluto is .25, Halley's Comet is .97 (off the scale).

Because Earth's orbit is not a perfect circle, the Earth is actually about 3 million miles closer to the Sun around January 2 than it is on July 4. Keep in mind that 3 million miles is not that much, considering the average distance between the Earth and Sun is about 93 million miles.

To view another interactive related to eccentricity, CLICK HERE.

No comments:

Post a Comment