Curious Dragonfly Monthly Science Newsletter The Moon

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1 Curious Dragonfly Monthly Science Newsletter The Moon EARTH'S SATELLITE The Moon (or Luna) is the Earth's only natural satellite. It was formed 4.6 billion years ago, about million years after the formation of the solar system. The Moon is in synchronous rotation with Earth, meaning the same side is always facing the Earth. But why is it known simply as 'the Moon?' Because for the longest time, ours was the only moon astronomers knew existed. This changed in 1610, when astronomer Galileo Galilei discovered four moons orbiting the planet Jupiter. MOON PROFILE! DIAMETER: 3,475km MASS: 7.35x10^22kg ORBITS: Earth ORBIT DISTANCE: 238,855mi ORBIT PERIOD: 27.3 Days SURFACE TEMP: -233 to 123ºC Earth's moon is the fifth largest in the solar system. It is the only place beyond Earth where humans have set foot. The brightest and largest object in our night sky, the Moon makes Earth a more livable planet by moderating it on its axis, leading to a relatively stabe climate. Tides are also caused by the Moon, creating a rhythm that has guided humans since the first prehistoric person looked up in the sky and saw it shining down in the dark. The Moon was likely formed after a Mars-sized body collided with Earth.

2 THE TRUTH ABOUT TIDES The word 'tide' is a generic term used to define the alternating rise and fall in sea level with respect to the land, produced by the gravitational of the moon and the sun. Tides also occur in lakes, the atmosphere, and the crust of the earth, though to a much smaller extent. Lunar tides are created because Earth and the Moon are attracted to one another like magnets. The Moon pulls at anything on Earth to draw it closer, and the Earth is able to hold on to most things -- except the water, The Moon and crashing waves. since it is always moving. This makes it easier for the Moon, whose gravitational pull is one ten-millionth of Earth's, to pull at it. This results in high and low tides, which occur twice each a day. There are about 12 hours and 25 minutes between high tides. Have you ever experienced the ocean at both high and low tide? OTHER TIDE TYPES SPRING TIDE: When The Moon is full or new, the gravitational pull of the Moon and Sun are combined. At this time, the high tides are very high, and the low tides are very low. This is also known as 'Spring Tide.' They occur when the Earth, the Sun, and the Moon are in a line, and are especially strong. NEAP TIDE: During the Moon's quarter phases, the Sun and Moon work at right angles, causing the bulges to cancel each other. The result is a smaller difference between high and low tide. This weaker tide is known as the 'Neap Tide.' Forces at work.

3 GOING THROUGH A PHASE One of the more interesting aspects of the Moon is its ability to change appearance each night. These are called the phases of the Moon. We can see a portion of the Moon that is illuminated by the Sun, and another portion that appears darkened. At different Phases of the Moon. times of the month, the Moon appears as a crescent, half-circle, or full disk. These phases are determined by the angle that the Sun shines on the Moon at various points each month. Phase 1: NEW MOON -- The side of the Moon facing the Earth is not lit up. At this time, the moon is not visible. Phase 2: WAXING CRESCENT -- A small part (less than 1/2) of the Moon is lit. The part that is lit is slowly getting bigger. Phase 3: FIRST QUARTER -- One-half of the Moon is lit up by the Sun. The part that is lit is still getting bigger. Phase 4: WAXING GIBBOUS -- At this time, over half of the Moon is lit, and is still growing. 'Waxing' means to slowly get larger. Phase 5: FULL MOON -- Surprise! This means, naturally, that the entire side of the Moon facing Earth is lit. Phase 6: WANING GIBBOUS -- The Moon is not quite lit up all the way by sunlight. The sunlit section is slowly getting smaller, or 'waning.' Phase 7: LAST QUARTER -- Once more, half of the Moon is lit up by the Sun. This time, the portion we see is getting smaller. Phase 8: WANING CRESCENT -- A small part of the Moon - opposite from the waxing crescent - is lit up, and getting smaller by the minute.

4 LUNAR ORIGINS After the sun spun to light, the planets of the solar system began to form. It took another 100 million years, however, for the Earth's Moon to be created. How it was created in not entirely certain. There are, however, three major theories. Numerous craters make up the Moon's topography. Giant Impact Theory -- This is the prevailing theory supported by the scientific community. Earth, having been formed from the leftover cloud of dust and gas orbiting the young sun, was the victim of a colossal impact by one of the many floating bodies hurtling through the young solar system. Known as Theia, the Mars-sized body collided with Earth, which threw chunks of the young planet's crust into space. Gravity bound the objects together, forming what would later be known as the Moon. Co-Formation Theory -- Since moons can form alongside their parent planets, this theory posits that gravity would have caused material in the early solar system to draw together at the same time as it bound particles together for Earth. Capture Theory -- Like the Martian moons Phobos and Deimos, this theory suggests Earth's gravity snagged a passing body and drew it into its own orbit. Rover tracks on the Moon surface. A new theory has emerged just this past January that suggests the Moon may have been formed through the merging of twenty 'Moonlets' following a series of asteroid strikes on Earth. This means that Earth may have once had many moons that, over time gathered together into one solid entity.

5 ONE SMALL STEP On July 20, 1969, American astronauts Neil Armstrong ( ) and Edwin "Buzz" Aldrin (1930- ) became the first humans to ever land on the Moon. Six hours later, Armstrong became the first person to set foot on the Moon's surface. It was as he took his first step that he said the famous line, "That's one small Apollo 11 lands on the Moon. step for man, one giant leap for mankind." The Apollo 11 mission occurred eight years after President John F. Kennedy announced to the world the United States's goal to land a man on the Moon by the end of the decade. At the time of President Kennedy's proclamation, the U.S. was trailing its Soviet counterparts in space development, and Cold War-era America welcomed his bold proposal. Were you alive for the Moon Landing? If so, what do you remember about the experience? In 1966, scientist at the National Aeronautics and Space Administration (NASA) conducted their first unmanned Apollo mission. After a tragic fire to a manned Apollo spacecraft in January 1967, the first successful trip around the dark side of the Moon occurred in December of the same year. This was followed in March of 1969 by Apollo 9, which tested the lunar module for the first time in Earth's orbit. That May, the three astronauts of Apollo 10 took the first complete spacecraft around the Moon in a dry run for the July event that would change the world. FUN FACT! Footprints left by astronauts like Buzz Aldrin on the Moon will be there for over a million years. There's no wind to blow them away!

6 MEN ON THE MOON At 9:32 a.m. EDT on July 16, while the whole world watched, Apollo 11 took off from Kennedy Space Center. The massive Saturn V rocket held three astronauts -- Armstrong, Aldrin, and Michael Collins (1930- ). ArmA unique perspective of the Moon. strong was the commander of the mission. After traveling 240,000 miles in just 76 hours, Apollo 11 entered lunar orbit on July 19th. The following day, at 1:46 p.m., the lunar module Eagle separated from the command module. Armstrong and Aldrin were aboard, while Collins stayed behind. Two hours later, the craft touched down on the southwestern edge of the Sea of Tranquility. Upon landing, Armstrong radioed Mission Control in Houston, Texas to proclaim: "The Eagle has landed." Five hours ahead of schedule, Armstrong opened the hatch of the lunar module. As he made his way down the ladder, a television camera on the craft beamed his image back to Earth, where hundreds of millions watched in amazement. At 10:56 p.m., Armstrong's feet touched the unblemished surface of the Moon, and he spoke the most famous quote of all time. Aldrin joined him twenty minutes later, and the two proceeded to plant an American flag, run a few tests, and speak with President Richard Nixon. Among the items left on the surface of the Moon was a plaque reading: "Here men from the planet Earth first set foot on the MoonJuly 1969AD - We came in peace for all Mankind." There would be five more lunar landing missions, as well as the infamous Apollo 13 lunar swingby (whose lunar landing was aborted). The last men to walk on the Moon were the crew of Apollo 17 on December 14, The crew of Apollo 11.

7 MOON ROCKS! Between 1969 and 1972, six Apollo missions brought back 842 pounds (382kg) of lunar rocks, core samples, pebbles, sand and dust from the Moon. The six space flights returned 2200 separate samples from six different exploration sites. In addition, three automated Soviet spacecraft returned important samples totaling approximately 3/4lb. (300g) from three other sites. The chief repository site for the Astronauts collect lunar soil, and a 2.2lb. rock brought Apollo samples is in the lunar sample back by Apollo 16. building at Johnson Space Center in Houston, Texas. This is where pristine lunar samples are prepared for shipment to scientists and educators. Nearly 400 samples are distributed annually for research and teaching projects. But what is the Moon made of? Moon rocks are mainly composed of oxygen, silicon, magnesium, iron, calcium, and aluminum. Other elements can be found in trace amounts, depending on the region. The lunar surface is composed of four types of igneous (or solidified magma or lava) rocks: basalt, anthracite, breccia, and lunar soil. SPACE X & THE MOON TOURISTS Though NASA's days of shooting for the Moon may be over, it seems like Elon Musk's SpaceX is getting ready to launch. In February, Musk confirmed that 2 private citizens have paid over $300 million dollars for a week-long trip around the Moon. The two anon-ymous individuals will fly aboard the Dragon 2 space capsule in late Musk said he'd give the first mission to NASA if the SpaceX founder Elon Musk. space agency is interested. How much would you pay to travel around the Moon?

8 TO THE MOON AND BACK For as long as man has stared up at the stars, the Moon has been a source of awe and fascination. And landing on its surface is just the beginning. Here are two examples of interesting Moon theories. The Shining What does Stanley Kubrick's frightening film version of Stephen King's horror novel have to do with the Moon? Some conspiracy theorists believe the Moon landing was Le Voyage dans la Lune faked, and that Kubrick directed the whole In the 1902 fantasy film, the Man thing. He planted clues in The Shining (like the Apollo in the Moon is struck by a spacecraft. 11 sweater seen above) as a veiled This fun imagery speaks to the long-standing confession a decade later. traditional belief that a face can be seen on the lunar surface. ENGAGING QUESTIONS! 1. Along with tides, what are other ways the gravitational pull affects Earth? 2. What do you feel is the best explanation for the Moon's formation? 3. Why was landing on the Moon a significant achievement for NASA? 4. What additional things can be learned from Moon rocks? 5. What do you feel will be the space program's next accomplishment? Curious Dragonfly LLC Trina Terrell