Maria vs. Highlands Maria is Latin for “seas”. These areas appear dark and have smooth relatively crater free surfaces. They represent the low lying areas that have been filled in with lava (basalt). Highlands are literally higher than the surrounding maria. They lighter in color (andesite) and completely covered by craters.
Maria vs. Highlands Sinus Iridiuim Bay of Rainbows Mare Imbrium - Sea of Rain Mare Serentatis – Sea of Serenity Mare Crisium- Sea of Crisis Mare Tranquilatatis – Sea of Tranquility Mare Fecundatatis – Sea of Fertility Mare Nectaris – Sea of Nectars Oceanus Procellarum – Ocean of Storms
Far Side vs Near Side The far side lacks Maria
Rays • Rays are streaks of dust and debris from the impact of large meteoroids • They radiate from the impact crater that created them • They cover great distances because the Moon lack an atmosphere to restrain them • They disappear over time so they represent recent impacts
Rays • Rays are streaks of dust and debris from the impact of large meteoroids • They disappear over time so they represent recent impacts
Scarps Scarps are faults. These areas show movement Of the crust.
Rilles • Rilles are collapsed lava tubes • These are underground rivers of magma that burn melt through the underground rocks. • They exist on all terrestrial planets
Rilles • Lava Tube • on Earth
Rebound mountains • These are much like the drop of water that jumps up after an object has pushed through the surface • Notice the rays and how the walls of the crater have collapsed due to steepness
Lunar Cycle • A few terms….. • Waxing = the amount visible is increasing • Waning = the amount visible is decreasing • Crescent = less than 50% visible. ½ of the cycle • Gibbous = more than 50% visible. ½ of the cycle • New Moon = Beginning of cycle (0% visible) • 1st Quarter Moon = ¼ of the way though the cycle (50% visible) • Full Moon = ½ way through cycle (100% visible) • 3rd Quarter Moon = ¾ of the way through cycle (50% visible)
Eclipses • The orbit of the Moon is tilted to the ecliptic. • This creates two points where the orbits cross called nodes • Each node represents an eclipse season where there can be a solar or lunar eclipse
Lunar Eclipses • Lunar eclipse always happen at the time of the Full Moon • The shadow of the Earth consists of two parts • Umbra = completely in the shadow. • Penumbra = partially in the shadow • Lunar eclipses last hours
Lunar Eclipses • Lunar eclipses provide evidence to the ancients that the Earth was round • The shadow that the Earth casts on the moon is round • The reddish brown color is due to light refracted through the Earth’s atmosphere
Solar Eclipse • Solar Eclipses always occur at New Moon • The Moon shadow does not completely cover the Earth so only a small percent of people on Earth get to see the solar eclipses • The shadow is only about 80 miles wide
Solar Eclipse • Totality only lasts less than 6 minutes • During totality we can see the atmosphere of the Sun called the Corona
Solar Eclipse • Annular eclipses occur when the moon is near apogee at the time of the eclipse • The last eclipse in Chicago was in 1994 and it was an annular eclipse