Just Mooning Around This Week

a year, while the Apollo astronauts of the 1960s and 1970s spent only three days journeying to the moon in a spacecraft. Light, on the other hand, travels at about 610 million miles per hour (186,282 miles per second) and takes little more than one second to make the journey from the moon to the Earth.

Suppose we could stand on the moon. Since the moon is much less massive than the Earth, its gravitational pull is significantly less as well -- one-sixth of what we normally feel here. That means that a person who weighs 120 pounds on the Earth would weigh only 20 pounds on the lunar surface.

This weaker lunar gravity would affect nearly everything we’ve grown accustomed to on our planet. Just imagine watching a lunar baseball game, for example, where a towering home run ball would sail for miles before finally coming to rest!

Temperatures on our natural satellite are also quite different than here on Earth. Since the moon has no significant atmosphere to absorb the sun’s heat and distribute it around the lunar globe, temperature extremes are common. A thermometer in direct sunlight would register about 273 degrees Fahrenheit, while one in the darkness would show a bone-chilling minus 244 F.

The visible features of the moon are also quite interesting. The large dark regions are ancient plains of solidified magma known as maria and always appear to face us here on Earth. Does that mean that the moon doesn’t rotate?

Not at all. The moon rotates, but the Earth’s relatively strong gravitation has locked one face in our direction. It’s much like tying a rope to a bucket handle and swinging it around you. The open part of the bucket always faces you, even though other people