Moon Notes

How much bigger is the Earth than the Moon?

• Earth radius = 6,385 km

• Moon radius = 1,738 km

• How much bigger by diameter or radius?

• 6385 km / 1738 km = 3.7

How much bigger is the Earth than the Moon?

• Earth radius = 6,385 km

• Moon radius = 1,738 km• Volume = 1.3 r3

– Earth 1.3 3.14 (6385)3 = 1.1 10 12 kg

– Moon 1.3 3.14 (1738)3 = 2.2 10 10 kg

» 1.1 10 12 kg / 2.2 10 10 kg = 50

How much bigger is the Earth than the Moon?

• Mass of Earth = 6.0 1024 kg

• Mass of Moon = 7.3 1022 kg

• 6.0 1024 kg / 7.3 1022 kg = 82

What does the mass and volume say about the density of the

moon?• Earth = 80 times the mass at 50 the volume

• The Earth is more dense than the moon• Earth is 5.5 g/cm3

• Moon is 3.3 g/cm3

How far away is the moon?

• Circumference of Earth = 40,000 km

• Distance to Moon = 400,000 km

Brightness of the Moon

• Albedo of Earth = 37%

• Albedo of moon = 7 to 11%

• Albedo of Venus = 59%

• Albedo of Mars = 16%

Surface Gravity

• 17 % or 1/6 of Earth’s gravity– How much would you weigh on the moon.

– Neal Armstrong had a 200 pound spacesuit on when he walked on the moon. If he stood on a lunar bathroom scale, how much would he weigh?

Phases of the Moon

Shadows

Shadows to Scale

Why don’t we get an eclipse every month?

Lunar Eclipse Schedule

Solar Eclipse Schedule

Lunar Eclipse

Lunar Eclipse