mgb_phys said:It's a conspriracy!
ps. Wiki gives it as 4.627 m/s
russ_watters said:I guess people just don't consider that factoid to be very important.
LURCH said:Generally, I think people find it more useful to measure the moon's rotation in comparison with its orbital period. "Miles" and "meters" are strictly man-made units of measure, so measuring the rotation of the moon in miles per hour or meters per second might seem (to some people) rather arbitrary. Referring to the time it takes the moon to complete one revolution on its axis as "one lunar orbit" is a much more relevant bit of information, for most applications.
tony873004 said:That's the Moon's rotational speed at the equator.
It's easy to compute: v=d/t = Moon's circumference / period = 2*pi*1737km/(27.32*24) = 16.645 km/hr, same as 10.3 mi/hr or 4.6 m/s.
But at the poles its velocity is 0. To get the speed for any latitude inbetween, multiply the equatorial speed by cos(latitude).
The moon exhibits three main types of motion: orbital motion around the Earth, rotational motion on its own axis, and libration motion caused by the moon's slightly elliptical orbit.
The moon's orbital speed varies, but on average it moves at a speed of about 1 km/s, or 2,288 miles per hour.
The moon takes approximately 27.3 days, or 27 days, 7 hours, and 43 minutes, to complete one orbit around the Earth.
The moon's orbital motion around the Earth, combined with the Earth's rotation on its axis, causes the moon to appear to move across the sky from East to West.
The moon's gravitational pull on the Earth's oceans causes the tides to rise and fall. The speed of the moon's orbital motion determines the frequency of tides, with two high tides and two low tides occurring every 24 hours and 50 minutes.