1. 1/14/20161

2. 2 The Moon - Facts Size - 3476 km across - 1/4 the size of Earth (like a tennis ball compared to a basketball) Average Distance from Earth - 384, 403 km (takes 6 days to travel there and back by rocket) Gravity - 1/6 of Earth Little or no atmosphere Night Temperature is -173º C Day Temperature is 127º C Brought to you by:

3. 1/14/20163 The Moon Surface - Craters Most numerous feature - about 3 trillion craters over 1 m wide various sizes - microscopic to 1100 km wide small craters are like little bowls larger craters (8-16 km wide) have level floors with high walls believed created when meteoroids, meteors, asteroids and comets crashed into the moon –no atmosphere so objects do not burn up as they would when approaching Earth some may have been created from volcanoes, and look like volcanic craters on Earth

4. 1/14/20164 The Moon Surface - Craters cont. Largest crater is the Imbrium Basin –1100 km wide with mountains around the rim –floor is made of lava –is visible from Earth Ray Craters - craters with gray streaks (rays) pointing out all around –probably formed by rocks thrown from craters –formed later in moon’s history because their rays cross over other features, such as marias and other craters –a large one is visible from Earth

5. 1/14/20165 The Moon Surface - Highlands & Lowlands Mountains –appear as light gray spots from Earth –believed to be parts of the rims of huge craters –some are over 6000 m –7920 m high near moon’s south pole - as tall as many of the Himilayas on Earth (Mt. Everest is 8898 m tall) Marias - broad flat plains –occurring mainly on the side of the moon we see –appear as dark gray spots from Earth –believed to have been formed by great lava flows about 3.5 million years ago

6. 1/14/20166 The Moon Surface - Rilles Long narrow valleys most are straight believed to have formed when the moon’s crust cracked and sections of the surface sunk down some are winding channels, probably formed by lava flows on the marias (plains)

7. 1/14/20167 The Moon Surface - Soil & Rocks Entire surface of moon covered by layer of rocks and soil which may be up to 6 meters deep on the maria Soil believed to be formed by grinding and churning of moon’s surface as meteoroids hit it Rocks contain minerals common on Earth such as aluminum, calcium, iron, magnesium plus a few not known to occur naturally on Earth Two main types collected by astronauts: –Basalt - hardened lava containing crystals such as feldspar, pyroxene and ilmenite –Breccia - conglomerate of soil and bits of rock squeezed together by heat and pressure when hit by meteoroids

8. 1/14/20168 The Moon - Orbit Orbit is oval so the moon is sometimes farther and sometimes closer to Earth Orbits or revolves around the Earth every 27 1/3 days in relation to the stars - sidereal month Orbits or revolves around the Earth every 29 1/2 days in relation to the sun - synodic or lunar month Rotates once every 27 1/3 days so we always see the same side of the moon Day and night are each about 15 Earth-days long The moon actually moves from west to east but it appears to move the other way because the Earth travels faster than the moon revolves around the Earth.

9. 1/14/20169 The Moon - Phases Waxing - moving from New Moon to Full Moon Waning - moving from Full Moon to New Moon As the moon travels around the Earth, we see different parts of its sunlit face so it appears to change shape. It takes on lunar month (29 1/2 days) to complete the cycle.

10. 1/14/201610 The Moon - Phases cont. New Moon - The moon is between the earth and the sun so we do not see any of its sunlit face. First Quarter - About a week later, we can see half of the sunlit face. Full Moon - Another week later we can see all of the sunlit face. Earth is now between the moon and the sun. Last Quarter - After about one more week, we can see only the other half of the moon.

11. 1/14/201611 The Moon - Lunar Exploration From ancient times, scientists and astronomers have studied the moon. For example, Aristarchus measured the distance to the moon around 280 B.C. 1600’s - Galileo used first telescopes to study the moon and J. Hevelius charted over 250 moon formations 1850’s - W. C. Bond and J. A. Whipple took first photos 1959 - Soviet Union spaceships - Luna 2 hit the moon and Luna 3 sent back first pictures of the far side 1964 - 65 - US spacecraft (Ranger 7, 8 & 9) took close up pictures 1966 - Soviet Union spacecraft Luna 9 made first soft landing on moon 1969 - 72 - US manned exploration on Apollo missions Since then, other spacecraft have photographed the moon, and collected other more detailed information. There have been no further manned missions.

12. 1/14/201612 The Moon - Apollo Missions 1968 - US Apollo 8 orbits around moon 10 times 1969 - July 20, Neil Armstrong was the first human to set foot on the moon - Apollo 11. Also Apollo 12 landed men on the moon in Nov. 1970 - Apollo 13 has explosion and nearly doesn’t make it back to Earth. 1971 - 72 - Apollo 14, 15, 16, and 17 land men on the moon for various explorations, including driving a battery-powered lunar roving vehicle.

13. 1/14/201613 The Moon - Conditions for Life No life - no aliens Little or no atmosphere - no air, wind or weather No water (although in 1998, the US space probe Pros-pector found evidence that there may be frozen water mixed with the soil at the poles) Temperatures range from -173º to 127º C

14. 1/14/201614 The Moon - Gravity The mass of the moon is about 81 times smaller than that of Earth. Therefore it does not have the same amount of gravitational pull. The moon has only about 1/6 the gravity of Earth. Therefore you would weigh only 1/6 as much on the moon!