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3 Common Questions (and answers) about Space
By Linda | February 14, 2008
1. How fast does the Earth turn?
A. The circumference of the Earth at the equator is 25,000 miles. The Earth rotates in about 24 hours. Therefore, if you were to hang above the surface of the Earth at the equator without moving, you would see 25,000 miles pass by in 24 hours, at a speed of 25000/24 or just over 1000 miles per hour. The Earth is also moving around the Sun at about 67,000 miles per hour.
2. Why doesn’t Earth’s atmosphere dissipate into the vacuum of space?
A. In the top layer of the atmosphere, that’s exactly what does happen. The thing is, at that altitude, Earth’s gravity is capturing and attracting molecules of air back into the atmosphere at the same rate, and it balances out.
3. How cold is space?
A. If you could measure the temperature in a deserted region of space, it would be about 2.7 degrees Kelvin (-454 degrees Fahrenheit). Zero degrees Kelvin is “absolute zero”, the temperature at which molecules have no kinetic energy and stand completely still. The reason that space is a few degrees warmer than absolute zero is because of microwave radiation left over from the original “big bang”.
Topics: Science Factoids, The Cosmos |
