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Planetary Bodies and Solar System Components

• Moon cycles include new moon, waxing crescent, first quarter, waxing gibbous, and full moon, with surface features such as Maria and Highlands.
• The moon was formed after an impact on Earth by a protostar named Theia, leading to the Condensation Theory.
• Venus rotates retrograde, has evidence of volcanic activity, temperatures of 450 degrees Celsius, a CO2 atmosphere, and a rigid crust.
• Mars, the red planet, is cold and dry, with extreme and longer seasons, half the size of Earth, and evidence of past water.
• The Solar System components include planets, asteroids, moons, dwarf planets, and comets.
• Asteroids are rocky or metallic objects larger than 100m across, while comets are composed of nucleus and some have a tail.
• Meteoroids are small, less than 1m across, meteors are the bright trail left behind, and meteorites are rocks from space that fall through Earth's atmosphere.
• Planets orbit the sun, are spherical, and have cleared their orbit, while dwarf planets have only orbited the sun and are spherical.
• Jupiter's moons, the Galilean moons, include Ganymede, Europa, Io, and Callisto, each with distinct characteristics.
• The Solar System has gas giants (Jupiter and Saturn) and ice giants (Neptune and Uranus).
• Terrestrial planets are inner planets with a composition of rock or iron, while Jovian planets are outer planets composed primarily of hydrogen and helium.
• Prograde motion is when the object spins in the same direction as its orbit, while retrograde motion is the opposite, and most planets have prograde motion.