More than 58 years have passed since Sputnik 1 became the first artificial satellite to orbit Earth. Launched by the Soviet Union on October 4, 1957, Sputnik 1 consisted of a 23-inch-diameter ...

The attractive force of gravity also keeps moons and artificial satellites in orbit around a planet. The Moon is a natural satellite. An artificial satellite is a man-made body placed in orbit ...

Fejer 1 and Scott 2 have given simple methods for estimating the remaining life-time of an artificial Earth satellite. Their methods do not apply when the eccentricity is small, and it is not ...