jump to other results. 1  1[countable] a particular attitude towards something; a way of thinking about something synonym viewpoint a global perspective Recent events seem less serious when put into an international perspective.
Low earth orbit is only slightly above the Earth, by outer space standards, 124 - 1240 miles (200 - 2000 km) in altitude. Below 124 miles, orbits rapidly degrade, causing surface impact, and above 1,240 miles or even less, the Earth's radiation belts damage electronic equipment, necessitating special shielding. The region from 1,243 miles altitude to geostationary orbit (35,786 kilometers or 22,236 mi) is known as Medium Earth Orbit.
View full size image. The orbit of the moon around the Earth is not a perfect circle so the distance varies a little. The average distance is around 384,400 kilometers or 230,600 miles. When NASA's Apollo astronauts flew to the moon in the late 1960s and early 1970s, it took them three days to reach the moon and enter orbit after launch.