Characteristics and Basic Facts The Moon Characteristics and Basic Facts
Basic Facts Earth’s only natural satellite Created approx. 4.6 bya (Impact Theory) Considered to be a double planet system with Earth Large size (2,200 miles diameter) Close to Earth (220,000 miles on average)
Basic Facts continued…. Point of gravitational attraction between Earth and moon is called the barycenter Gravitational attraction helps to create tides on Earth We always see the same side of the moon from Earth due to its slow rotation.
Surface Features Layered moon with crust, mantle and inner core (all solid) Virtually inactive No atmosphere, no erosion, no wind, water, ice, no change!! Low gravity (1/6 of Earth)
Features continued…… Extreme temperatures Sun Side= 212 °F Dark Side= -150 °F Highly cratered due to meteorite impact Dark, low lying areas or craters called Maria (seas) Canyons called Rillies Debris streaks from craters called Rays Dust covering surface of moon called Regolith
Rilles
Maria
Rays
Regolith
Behavior Moon appears to go through phases (changes in size and shape) Phases created by the angle of the Sun, moon and Earth Synodic Month —Time for Moon to go through phases (29.5 days) Sidereal Month —Actual Revolution around Earth (27.3 days)
Phases of the Moon Waxing: Moon appears to be increasing in size Waning: Moon appears to be decreasing in size Full Moon: Phase when all of the moon’s surface is visible New Moon: Phase when none of the moon’s surface is visible
EARTH