The Moon

Lunar Surface

•maria: smooth, dark areas of the moon- reflect little light–maria are plains of dark solidified lava

•craters: bowl-shaped depressions on the moon –lunar craters are formed from impacts of debris

•regolith: layer of dust and rock that covers the moon’s surface

Interior of the Moon

•Why does the same side of the moon always face us?

•Because the moon rotates and revolves at the same speed (27 1/3)

Eclipses•when one planetary body passes

through the shadow of another

•solar eclipse: when the moon is directly between the Earth and the sun

•lunar eclipse: when the Earth is directly between the moon and the sun

•Eclipses don’t occur every month because the moon’s orbit is tilted with respect to the Earth’s orbit

Moon Phases

•phases: various shapes of the moon lighted by reflected sunlight

•waxing: when the size of the visible portion of the moon is increasing

•waning: when the size of the visible portion of the moon is decreasing

•new moon: no lighted area of the moon is visible from the Earth

•full moon: entire half of the side of the moon facing Earth is lit

•crescent: less than half of the side facing the Earth is lit

•gibbous: more than half of the side facing the Earth is lit

Waxing crescent

1st quarter

New moon

Waxing gibbous

Full moon Waning gibbous

3rd quarterWaning crescent

Tides•tides: daily changes in the level

of the oceans-caused by the moon’s

gravitational pull-tide changes every 6 hours

Tide animation: The spinning Earth within a slightly elliptical ocean results in the rising and falling of the ocean surface, with respect to the land, over the course of a day. For each 24 hour period there are two high tides and two low tides as the Earth rotates through each of the two bulges of the the ocean surface

•spring tide: tide with maximum daily tidal range that occurs during new and full moons

•neap tides: tides with minimum daily tidal range that occurs during 1st and 3rd quarter moons