Free Republic 4th Qtr 2025 Fundraising Target: $81,000 Receipts & Pledges to-date: $17,088
21%  
Woo hoo!! And now $732 to reach 22%!! Thank you all very much!! God bless.

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  • How fast is the earth moving?

    01/09/2016 6:12:50 PM PST · by MtnClimber · 65 replies
    Scientific American ^ | 26 Oct, 1998 | Rhett Herman
    Consider the movement of the earth's surface with respect to the planet's center. The earth rotates once every 23 hours, 56 minutes and 4.09053 seconds, called the sidereal period, and its circumference is roughly 40,075 kilometers. Thus, the surface of the earth at the equator moves at a speed of 460 meters per second-or roughly 1,000 miles per hour. As schoolchildren, we learn that the earth is moving about our sun in a very nearly circular orbit. It covers this route at a speed of nearly 30 kilometers per second, or 67,000 miles per hour. In addition, our solar system--Earth...