The Leap Second

The earth's circumference along the equator is 40,052km or 40,052,000m. The actual time it takes the earth to rotate 360^ (we'll say ^ is degrees) is 23 hours, 56 minutes, and 4 seconds, or 86,164 seconds [Period of Rotation of the Earth - The Physics Factbook].Using these two numbers you can find the earth's velocity. d=vt, so 40,052,000=v x 86,164. v then equals approximately 464.83 m/s.Knowing the velocity, you can now determine the distance the earth travels in 24 hours, or 86,400 seconds. d=vt, so d=464.83 x 86,400 or 40,161,312m.Using the actual circumference of the earth, you can determine the distance in meters of 1^. 40,052,000m/360^ gives you 111,255.56m per degree.Then, dividing the distance the earth travels in 24 hours by the number of meters per degree will give you the number of degrees the earth travels in 24 hours. 40,161,312/111,255.56 gives you 360.98^ in one day, or 360^58'59".

Thankyou for making maths so complicated An easier method of estimating it would be to use to use 360^ divided by 365.25 days. You get 0^59'8". Adding this to the normal 360^, you get 360^59'8", which is actually quite close to phil's answer.

was total BS.The writer of that article totally screwed up his definitions and wrote nonsense.

Eta, are you refering to the post and numbers in msg 16? It is a bit unfair to say something is screwed up without pointing out where it is.

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Common sense isn't

The only CNN article was in the original post. I saw it the morning it appeared on CNN (before it was posted here.) It's garbage.

I don't think the number of days in a year has anything to do with minnemooseus' original post. It has to do with the rotation of the earth, not the revolution.Maybe you were confused by my original post, though. I should have clarified what I meant by "the distance the earth travels." I meant the distance A POINT on earth travels in however much time. For one complete rotation of the earth, this distance would simply just be the circumference of the earth. When you take into account the full 24 hours, though, the distance becomes more.

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I don't think the number of days in a year has anything to do with minnemooseus' original post. It has to do with the rotation of the earth, not the revolution.

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My answer of ~361 degrees per day came from Rrhains information of message 4. Although not explicitly stated, I'm pretty confident that the calculations of his numbers involved the number of days in a year.I must presume that the convention of dividing the circle into 360 degrees is because of the year being approximately 360 days long. If the year was indeed precisely 360 days, and the earth's orbit was precisely circular, then the earth would rotate exactly 361 degrees per day (reference point facing precisely towards sun to same point precisely towards sun).The ellipticity of the earth's orbit throws a little variability into the "picture".Variation in the earth's rotation speed will throw a little variability into how long it takes to rotate that 361 degrees.Moose