12am:The Iron Mountain, MI forecast for Apr 14 is 53 degrees and Overcast. There is 49 percentage chance of rain and 11 mph winds from the Southeast. 3pm:The Iron Mountain, MI forecast for Apr 14 is 53 degrees and Patchy rain possible. There is 49 percentage chance of rain and 11 mph winds from the Southeast.
The earth's orbit around the sun is elliptical, so the earth moves at a constantly varying velocity as it moves closer to the sun (perihelion) or further away (aphelion). The earth's angular velocity (speed of movement) is considerably greater at perihelion than it is at aphelion.he earth gets through 10% of its path in the same length of time whether it is at aphelion (moving slowly) or perihelion (moving fast). The absolute speed at which the earth moves varies, but the rate at which it orbits is constant.
1 Semi-synchronous orbit: An orbit with an orbital period equal to half of the average rotational period of the body being orbited and in the same direction of rotation as that body. 2  For Earth this means a period of just under 12 hours at an altitude of approximately 20,200 km (12,544.2 miles) if the orbit is circular. Geosynchronous orbit (GSO): An orbit around the Earth with a period equal to one sidereal day, which is Earth's average rotational period of 23 hours, 56 minutes, 4.091 seconds. 2  For a nearly circular orbit, this implies an altitude of approximately 35,786 kilometers (22,236 mi).