Scale: 109 meters = 1 Gm = 1 gigameter: Light requires 3 seconds to cross this picture.

Earth and Moon

As in the last image, we see only the local volume of space around our Earth and Moon. Within this 1 million km cubed (or 1027 cubic meters) there are only the Earth with its Moon -- and a few thousand man-made satellites. The Moon's orbit is nearly 400 000 km from Earth.

Earth's orbit about the Sun is indicated by the nearly straight line from upper right to lower left, while the Moon orbits counterclockwise on the ellipse. The Moon's orbit is seen as highly elliptical instead of nearly circular because we are looking from directly above San Francisco at latitude 40°N instead of above the Earth's north pole.

Copyright © 2016 by Bruce Bryson