Curious Dragonfly Monthly Science Newsletter

The MoonEARTH'S SATELLITE

The Moon (or Luna) is the Earth's only natural satellite. It was formed 4.6 billion years ago, about 30-50 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 astro-nomer Galileo Galilei discoveredfour moons orbiting theplanet 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 sys-tem. It is the only placebeyond Earth where humans have set foot. The brightest and larg-est object in our night sky, the Moon makes

Earth a more livable planet by mod-erating 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.

THE TRUTH ABOUT TIDES

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Have you ever experienced the ocean at both high and low tide?

The Moon and crashing waves.

The word 'tide' is a generic term used to de-fine the alternating rise and fall in sea levelwith respect to the land, produced by the gravitational of the moon and the sun. Tidesalso occur in lakes, the atmosphere, and thecrust of the earth, though to a much smaller extent.

Lunar tides are created because Earth and the Moon are attracted to one another likemagnets. 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,since it is always moving. This makes it eas-

ier 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.

OTHER TIDE TYPESSPRING TIDE: When The Moon is full or new, the gravitational pull of the Moon andSun are combined. At this time, the high tides are very high, and the low tides arevery low. This is also known as 'Spring Tide.'They occur when the Earth, the Sun, and the Moon are in a line, and are especiallystrong.

NEAP TIDE: During the Moon's quarterphases, the Sun and Moon work at rightangles, causing the bulges to cancel eachother. The result is a smaller difference betweenhigh and low tide. This weaker tide is known asthe 'Neap Tide.'

Forces at work.

GOING THROUGH A PHASEOne of the more interesting aspects of theMoon 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 times of the month, the Moon appears as acrescent, 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.

Phases of the Moon.

LUNAR ORIGINS

Numerous craters make up the Moon's topography.

Rover tracks on the Moon surface.

After the sun spun to light, theplanets of the solar system beganto form. It took another 100 millionyears, however, for the Earth'sMoon to be created. How it wascreated in not entirely certain.There are, however, three majortheories.

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 im-pact 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.

A new theory has emerged just this past January that suggeststhe Moon may have been formedthrough the merging of twenty'Moonlets' following a series of asteroid strikes on Earth. This means that Earth may have oncehad many moons that, over timegathered together into one solidentity.

ONE SMALL STEP

Apollo 11 lands on the Moon.

On July 20, 1969, American astronautsNeil Armstrong (1930-2012) and Edwin"Buzz" Aldrin (1930- ) became the firsthumans to ever land on the Moon. Sixhours later, Armstrong became the firstperson to set foot on the Moon's surface.It was as he took his first step that hesaid the famous line, "That's one smallstep for man, one giant leap for man-

kind." 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.

In 1966, scientist at the NationalAeronautics and Space Admini-stration (NASA) conducted theirfirst unmanned Apollo mission.After a tragic fire to a mannedApollo spacecraft in January 1967,the first successful trip around the dark side of the Moon occurred inDecember of the same year. This was followed in March of 1969 byApollo 9, which tested the lunarmodule for the first time in Earth'sorbit. That May, the three astro-nauts of Apollo 10 took the firstcomplete spacecraft around theMoon in a dry run for the Julyevent 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!

Were you alive for the Moon Landing? If so, what do you remember about the experience?

At 9:32 a.m. EDT on July 16,while the whole world watched,Apollo 11 took off from KennedySpace Center. The massive Saturn V rocket held three astro-nauts -- Armstrong, Aldrin, andMichael Collins (1930- ). Arm-strong was the commander ofthe mission. After traveling 240,000 miles in just 76 hours, Apollo 11entered 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. Uponlanding, 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 planetEarth first set foot on the Moon-July 1969AD - We came in peace for all Mankind."

There would be five more lunarlanding missions, as well as theinfamous Apollo 13 lunar swing-by (whose lunar landing wasaborted). The last men to walkon the Moon were the crew of Apollo 17 on December 14,1972.

MEN ON THE MOON

A unique perspective of the Moon.

The crew of Apollo 11.

MOON ROCKS!

Astronauts collect lunar soil, and a 2.2lb. rock brought

back by Apollo 16.

SPACE X & THE MOON TOURISTS

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 approx- imately 3/4lb. (300g) from three other sites. The chief repository site for the Apollo samples is in the lunar sample building at Johnson Space Center in

Houston, Texas. This is where pristine lunar samples are prepared forshipment to scientists and educators. Nearly 400 samples are distributedannually for research and teaching projects.

But what is the Moon made of? Moon rocks are mainly composed of oxy-gen, silicon, magnesium, iron, calcium, and aluminum. Other elements can be found in trace amounts, depending on the region. The lunar sur-face is composed of four types of igneous (or solidified magma or lava) rocks: basalt, anthracite, breccia, and lunar soil.

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 2018. Musk said he'd give the first mission to NASA if the space agency is interested.

SpaceX founder Elon Musk.

How much would you pay to travel around the Moon?

Curious Dragonfly LLCTrina Terrellwww.curiousdragonfly.com303.903.5319

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?

TO THE MOON AND BACKFor 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.

Le Voyage dans la LuneIn the 1902 fantasy film, the Man

in the Moon is struck by a spacecraft.This fun imagery speaks to the long-standing

traditional belief that a face can be seen on the lunar surface.

The ShiningWhat 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 wasfaked, and that Kubrick directed the whole

thing. He planted clues in The Shining (like the Apollo 11 sweater seen above) as a veiled

confession a decade later.