> The Earth's figure axis is not the same as its north-south axis in space, which it spins around once every day at a speed of about 1,000 mph (1,604 kph). The

> The Earth's figure axis is not the same as its north-south axis in space, which it spins around once every day at a speed of about 1,000 mph (1,604 kph). The figure axis is the axis around which the Earth's mass is balanced and the north-south axis by about 33 feet (10 meters). Could someone explain this paragraph? how does one measure a rotation speed in terms of distance over time ? And I just cant figure what the second sentence means at all...