Moon

Cards (21)

  • Moon
    • Surface dominated by impact craters
    • Some filled with volcanic flows (maria)
    • No atmosphere
    • Same side always faces the earth (tidally locked)
  • Moon is smaller in density than Venus, Mars, and Earth
  • Gravity on the Moon is 1/6th that of Earth
  • Moon's orbital period matches its tidally locked rotation
  • Intense engineering designs are required to counteract the Moon's cold and warm conditions
  • Phases of the Moon
    Cyclical changes in the Moon's appearance as seen from Earth
  • Moon's gravitational pull on Earth and oceans
    Creates high and low tides
  • High tide is always aligned with the Moon
  • Lunar exploration programs
    • USSR Luna program (1959-1976)
    • US Ranger, Lunar Orbiter, and Surveyor missions (1961-1968)
    • Lunar Reconnaissance Orbiter (2009)
    • Chang'e 3 / Yutu (2013)
    • Chang'e-5 spacecraft (2020)
  • Over 100 spacecraft have been launched to explore the Moon
  • The USSR Luna program was the first to visit the Moon
  • The US Ranger, Lunar Orbiter, and Surveyor missions paved the way for human exploration
  • China's Chang'e 3 / Yutu was the third nation to successfully land a spacecraft on the Moon
  • China's Chang'e-5 spacecraft returned lunar samples in 2020
  • The Apollo missions (1969-1972) landed 12 astronauts on the Moon and returned 382 kg of rock and soil
  • Lunar rock types
    • Anorthosite
    • Basalt
    • Breccia
    • Regolith (lunar soil)
    • Glass
  • Lunar near side
    • Lunar Maria - Basaltic lava emplaced from fissures, relatively young (formed ~4 – 3.2 Ga)
  • Lunar far side
    • Terrae (highlands) - Local relief of 5000m, abundant craters (50 - 1000 km), anorthosite and feldspar-rich rocks, covers 80% of surface
  • Lunar volcanic features
    • Very fluid lavas
    • Sinuous rills (similar to lava tubes)
    • Smooth low domes
  • Lunar tectonic features
    • Linear rills (flat-floored, steep-walled troughs similar to grabens)
    • Wrinkle ridges (compressional features from contraction as moon cooled)
  • Formation of the Moon (4.6-4.5 Gy)
    1. Mars-sized object impacting differentiated Earth
    2. Debris from Earth and impactor accumulating to form the Moon
    3. Global magma ocean
    4. Differentiation: Less dense rocks migrating upward, cooling, and forming lunar crust