Scale: 1011 meters = 100 Gm = 100 gigameters

Venus, Earth, and Mars

Spacecraft from Earth have successfully soft-landed on just three planets, one moon, and one asteroid (Eros, a near-Earth asteroid) -- all located within this picture. Mars has been visited by the two Viking Landers and Mars Pathfinder. The Soviet Union managed eight soft landings on Venus, with at least four successfully returning pictures of Venus' rocky surface. The Moon has had several soft landings, including the 6 manned Apollo Lunar missions. And, of course, there have been scores of soft landings on our own planet by astronauts and cosmonauts returning from Earth orbit and the Moon. Once again, the stellar background remains unchanged because the stars are so far away that our smaller and smaller jumps have no impact on their relative positions.

The planets themselves are much smaller than a single pixel in this image. The planets would be very difficult to detect against the stellar background. You would need to be looking in the right spot at the right time and there is a huge volume of space in which to look. The portion of Earth's orbit shown here is traversed in about six weeks in July and August.

Copyright © 2016 by Bruce Bryson