1. The Moon Itself Structure and Atmosphere

2. Basic Lunar Stats Radius: 1,738 km ( 26 % of Earth’s) Mass:.0123 Earth Masses (7.349 x 10^22 kg) Density: 3.34 g/cm³ Surface Gravity: 1.6 m/s² (1/6 of Earth’s) Temperature: Low: -173ºC (-280ºF) (Perhaps -240°C ( -400°F) in deep craters) High: 130°C (260°F) Orbital Radius: 384,400 km (240,000 miles)

3. The Lunar Atmosphere For all practical purposes the Moon has no atmosphere. The lack of an atmosphere is why temperatures vary so greatly…no greenhouse effect There is slightly more helium near the Moon’s surface than in space, but not enough to count as an atmosphere. Near the poles there are traces of hydrogen. Source? Frozen Water from comets that has collected in the inside of polar craters that are permanently dark and thus cold.

4. Water Ice Confirmed on Moon In November 2009 a space probe was delibrately crashed into a crater near the Moon’s South Pole. Another probe flew through the resulting “splash” of debris and confirmed the presence of water ice!

5. The Regolith Collisions of asteroids and meteoroids with the moon have created the Regolith It is a light colored layer of dust and rock

6. Lunar Layers Regolith: Tens of meters thick. Crust: made of Silicates, rigid 60 km thick on near side. 100 km on far side. Mantle: about 1300km thick. Denser than crust, but rigid Core: Metallic, Iron and Nickel, very small. The core is off center…closer to near side. Earth’s gravity affects core and crust.