Here are 10 additional facts about our natural satellite that you might like.
The day-old Moon sets at Palomar Mountain Observatory in California near the 200-inch Hale Telescope dome. Note that the dome’s shutters are open in anticipation of a clear night.
Credit: Behyar Bakhshandeh
If you missed my first 10 cool things about the Moon, you can read them here. Now you’re ready for 10 more.
#11. The Moon’s temperature can vary from 242° Fahrenheit in a sunny spot to −334° Fahrenheit in a shady spot near one of its poles. On the Celsius scale, that’s a range from 117° to −203°.
#12. The ratio of the sizes of Earth and the Moon — 27.6 percent — is far larger than any other planet/satellite combination. The next nearest ratio — 5.5 percent — describes Neptune and its largest moon, Triton.
#13. The Moon is currently moving away from Earth at a rate of about 1½ inches (3.8 centimeters) per year, with an accuracy of about 1/32 of an inch (0.08 centimeter).
#14. The Moon is the major influence for ocean tides on Earth. Our satellite has twice as much effect on the tides as the Sun does.
#15. The Full Moon, though bright, is only 1/400,000 as bright as the Sun. If the entire sky were covered with Full Moons, we would receive only about one fifth the illumination of the Sun on a bright day.
#16. It wasn’t Columbus who proved Earth was round. In the fourth century BC, Greek philosopher Aristotle showed that Earth was a sphere by noting that our planet’s shadow always appears round during lunar eclipses.
#17. All parts of the Moon see the same amount of sunlight and darkness. So, although I am a Pink Floyd fan, I’m sorry to say there is no dark side of the Moon. Fifty percent of it is always dark, but the areas covered continually change as sunrise and sunset occurs.
#18. I find this one fascinating. Although the First and Last Quarter Moons show us 50 percent of the lit area of a Full Moon, each is only about 10 percent as bright as the Full Moon. The reason? The angle at which sunlight strikes the Moon.
#19. Earthshine, the “lighting up” of the Moon’s dark area a few days before or after New Moon , happens because sunlight refl ects off Earth and falls on the Moon, slightly illuminating the part we normally wouldn’t see. Earthshine also goes by the names “ashen glow” and “the old Moon in the new Moon’s arms.”
#20. Astronomers call the dividing line between the light and dark parts of the Moon the terminator . Between New Moon and Full Moon (that is, as the Moon’s face is waxing, a word that means “growing”), the terminator shows where sunrise is happening. Between Full Moon and New Moon (when the Moon’s face is waning, a word that means “shrinking”), it is the line of sunset.
