What is the Moon's Real Name? - Reach The Sky
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What does an Astronomer do? “ R E A C H T H E S K Y ” E R A S M U S + P A R T N E R S H I P F E B R U A R Y , 2 0 1 7 What is the Moon’s Real Name? As of 2015, there are 146 official moons in 1610, and realized that Jupiter had tiny spots the Solar System, and then another 27 provi- of light orbiting around it, astronomers had sional moons, who are still waiting on the status no idea other planets had moons. In Latin, of their application. All official moons have our satellite's name is "Luna." Because a signif- names after gods or Shake- icant chunk of English comes from Latin, speare characters, names many terms associated with like Callisto, Titan, or Pro- the moon are related to this metheus. But there’s one Latin name — for example, the moon in the Solar System adjective "lunar," and the noun with a super boring "lunatic," an old-fashioned name… the one you’re word for a mentally ill person. most familiar with: Moon. (Madness was thought to be So what’s the Moon’s real correlated with the phases of name? Its scientific name? the moon.) The answer is: The Moon. In Greek, our moon is Earth's moon does have a named "Selene," as is the name: In English, Interna- moon goddess of ancient tional Astronomical Union, Greek mythology. The English the body in charge of nam- word "selenology," or the ing celestial objects ap- study of the moon's geology, proved the name "The derives from it. If we want to Moon." The word moon is be sure you're talking about Proto-Germanic in origin, "The Moon" and not about "a deriving from a similar- moon" just put a capital "M" in sounding word that came into use a few thou- front of "oon". Using the same rule, the INSIDE THIS sand years ago in Northern Europe. name of our solar system is "Solar System", ISSUE: For most of human history, there didn't need the name of our galaxy is "The Galaxy" , even Selenography 6 the universe is "Universe", all with capital to be a more specific term to differentiate our moon from other moons that orbit other plan- letter. The Man on the 11 ets in the solar system, and for good reason: we Finally, If you want to be the godparent of Moon didn't know there were any other moons. Until our natural satellite you could invent a fancy Apollo Missions 12 Galileo first turned his telescope to the skies in name for "The Moon":). (Csabi Brezan)
PAGE 2 The Moon — Scientific facts Short description of The Moon made of minerals like olivine and pyroxene, which are made up of magnesium, iron, silicon and oxygen atoms. The crust The fifth largest moon in the solar system, Earth's moon has a thickness of about 43 miles (70 kilometers) on the is the only place beyond Earth where humans have set foot. Moon's near-side hemisphere and 93 miles (150 kilometers) The brightest and largest object in our night sky, The Moon on the far-side. It is made of oxygen, silicon, magnesium, iron, makes Earth a more livable planet by moderating our home calcium and aluminum, with small amounts of titanium, urani- planet's wobble on its axis, leading to a relatively stable um, thorium, potassium and hydrogen. climate. It also causes tides, creating a rhythm that has guid- ed humans for thousands of years. The Moon was likely Long ago the Moon had active volcanoes, but today they formed after a Mars-sized body collided with Earth. are all dormant and have not erupted for millions of years. With too sparse an atmosphere to impede impacts, a steady With a radius of 1,079.6 miles (1,737.5 kilometers), the rain of asteroids, meteoroids and comets strikes the surface moon is less than a third the width of Earth. If Earth were of the Moon, leaving numerous craters behind. Tycho Crater the size of a nickel, the moon would be about as big as a is more than 52 miles (85 kilometers) wide. coffee bean. Over billions of years, these impacts have ground up the The Moon is farther away from Earth than most people surface of the Moon into fragments ranging from huge boul- realize. The Moon is an average of 238,855 miles (384,400 ders to powder. Nearly the entire Moon is covered by a kilometers) away. That means 30 Earth-sized planets could rubble pile of charcoal-gray, powdery dust and rocky debris fit in between Earth and the Moon. The Moon is slowly called the lunar regolith. Beneath is a region of fractured moving away from Earth, getting about an inch farther away bedrock referred to as the megaregolith. each year. The light areas of the Moon are known as the highlands. The Moon is rotating at the same rate that it revolves The dark features, called maria (Latin for seas), are impact around Earth (called synchronous rotation), so the same basins that were filled with lava between 4.2 and 1.2 billion hemisphere faces Earth all the time. Some people call the years ago. These light and dark areas represent rocks of dif- far side — the hemisphere we never see from Earth — the ferent composition and ages, which provide evidence for "dark side," but that's misleading. As the Moon orbits Earth, how the early crust may have crystallized from a lunar mag- different parts are in sunlight or darkness at different times. ma ocean. The craters themselves, which have been pre- The changing illumination is why, from our perspective, the served for billions of years, provide an impact history for the Moon goes through phases. During a "full moon," the hemi- Moon and other bodies in the inner solar system. sphere of the Moon we can see from Earth is fully illuminat- ed by the sun. And a "new moon" occurs when the far side If you looked in the right places on the Moon, you would of the Moon has full sunlight, and the side facing us is having find pieces of equipment, American flags, and even a camera its night. left behind by astronauts. While you were there, you'd notice that the gravity on the surface of the Moon is one-sixth of The Moon makes a complete orbit around Earth in 27 Earth's, which is why in footage of moonwalks, astronauts Earth days and rotates or spins at that same rate, or in that appear to almost bounce across the surface. same amount of time. Because Earth is moving as well — rotating on its axis as it orbits the sun — from our perspec- The temperature reaches about 260 degrees Fahrenheit tive, the Moon appears to orbit us every 29 days. (127 degrees Celsius) when in full sun, but in darkness, the temperatures plummets to about -280 degrees Fahrenheit (- The leading theory of The Moon's origin is that a Mars- 173 degrees Celsius). The Moon has a very thin and weak sized body collided with Earth about 4.5 billion years ago. atmosphere, called an exosphere. It does not provide any The resulting debris from both Earth and the impactor ac- protection from the sun's radiation or impacts from meteor- cumulated to form our natural satellite 239,000 miles oids. The many missions that have explored the Moon have (384,000 kilometers) away. The newly formed Moon was in found no evidence to suggest it has its own living things. a molten state, but within about 100 million years, most of However, the Moon could be the site of future colonization the global "magma ocean" had crystallized, with less-dense by humans, though there are no immediate plans to do so. rocks floating upward and eventually forming the lunar crust. Earth's Moon has no moons of its own. The Moon has no rings. The early Moon may have developed an internal dyna- Earth's Moon has a core, mantle and crust. The Moon's mo, the mechanism for generating global magnetic fields for core is proportionally smaller than other terrestrial bodies' terrestrial planets, but today, the Moon has a very weak mag- cores. The solid, iron-rich inner core is 149 miles (240 kilo- netic field. The magnetic field here on Earth is many thou- meters) in radius. It is surrounded by a liquid iron shell 56 sands of times stronger than the Moon's magnetic field. Hu- miles (90 kilometers) thick. A partially molten layer with a man beings have studied the Moon for millennia, watching its thickness of 93 miles (150 kilometers) surrounds the iron phases change and observing eclipses — both solar and lunar. core. During a solar eclipse, our Moon moves between Earth and The mantle extends from the top of the partially molten the sun and blocks the sunlight. (Gal Andrea) layer to the bottom of the Moon's crust. It is most likely
The Moon — Scientific facts PAGE 3 Does Earth have a second moon? There are two kinds of planets in the solar system: the Terrestrial planets (Mercury, Venus, Earth, Mars), and the Jovian planets (Jupiter, Saturn, Uranus, Neptune). While the Jovian planets have a total observed number of moons of close to 90, the Terrestrial plan- ets have only 3 (the Moon, and two small moons around Mars). This huge difference is linked to the formation of the solar system. Quasi-satellites are not second moons for Earth. A quasi-satellite is an object in a co-orbital configuration with Earth (or another planet). Scientists would say there is a 1:1 orbital resonance be- tween Earth and this object. In other words, a quasi-satellite is or- biting the sun, just as Earth is. Its orbit around the sun takes exactly Earth Captures a Minimoon the same time as Earth’s orbit, but the shape of the orbit is slightly different. The most famous quasi-satellite in our time – and an object you might have heard called a second moon for Earth – is 3753 Cruithne. This object is five kilometers – about three miles – wide. Notice it has an as- The first modern idea teroid name. That’s because it is an asteroid orbiting our sun, one of several thousand asteroids whose about the formation of orbits cross Earth’s orbit. Astronomers discovered Cruithne in 1986, but it wasn’t until 1997 that they fig- the Moon was called ured out its complex orbit. It’s not a second moon for Earth; it doesn’t orbit Earth. But Cruithne is co- the fission theory, and orbiting the sun with Earth. Like all quasi-satellites, Cruithne orbits the sun once for every orbit of Earth. it came from George Orbits like that of Cruithne aren’t stable. Computer models indicate that Cruithne will spend only another Darwin, the son of 5,000 years or so in its current orbit. That’s a blink on the long timescale of our solar system. The asteroid Charles Darwin. He might then move into true orbit around Earth for a time, at which time it would be a second moon – but reasoned the Moon not for long. Astronomers estimate that, after 3,000 years orbiting Earth, Cruithne would escape back into must have broken orbit around the sun. away from our planet, Earth does sometimes have temporary moons. In March of 2012, astronomers at Cornell University pub- when the Earth was lished the result of a computer study, suggesting that asteroids orbiting the sun might temporarily become still a rapidly rotating natural satellites of Earth. In fact, they said, Earth usually has more than one temporary moon, which they ball of molten rock. called minimoons. These astronomers said the minimoons would follow complicated paths around Earth His theory lasted from for a time, as depicted in the images above and below. Eventually, they would break free of Earth’s gravity the 1800s right up until – only to be immediately recaptured into orbit around the sun, becoming an asteroid once more. The little the space age. moons envisioned by these astronomers might typically be only a few feet across and might orbit our planet for less than a year before going back to orbit the sun as asteroids. (Gal Alexandra) Theia Theia is a hypothesized ancient planetary- mass object in the early Solar System that, according to the giant impact hypothesis, collided with the early Earth around 4.31 billion years ago. In mithology, Theia was named for the titaness Theia, who in Greek mythology was the mother of Selene, the goddess of the moonAccording to the hy- pothesis, Theia was an Earth trojan about the size of Mars, with diameter of about 6,000 km (3,700 miles). Geologist Edward Young of the University of California, Los Angeles, drawing on an analysis of rocks collected by Apollo missions 12, 15, and 17, suggests that Theia collided head-on with Earth, in contrast to the previous theory that suggested a glancing impact. Models of the impact propose that Theia's debris gath- ered around Earth to form the early Moon. Some scientists think that the material thrown into orbit originally formed two moons that later merged to form the single moon we know today. The Theia hypothesis also explains why Earth's core is larger than would be expected for a body its size: according to the hypothesis, Theia's core and mantle mixed with Earth's. (Brezan Csaba)
PAGE 4 The Moon— Moon phases Several people have no- Moon Phases ticed that February 1999 has no Full Moon, and The truth is that we only see one side of the moon at all times; the near side. The far side have asked me how often of the moon is the part facing away from the Earth. Why do we only see one side of the that happens. In 1999, moon? Well, since the moon completes one axial rotation at the same time is completes 1 January and March both orbit around the Earth, we only get to see one side. This is what makes the moon appear it have two Full Moons. The is changing shape in the sky. Every 29.5 days the moon will show its 4 different faces it has second Full Moon in Janu- to offer and repeat itself in this cycle continuously. I also hope we know that the Earth does ary occurs late on the not emit light off on its own and that it is a reflection of the sun. 31st, whilst the first Full When the Moon appears smaller than a quarter, we call it a crescent. When the Moon Moon of March falls close appears larger than a quarter, we call it gibbous. When the moon is getting bigger (phases to the beginning of the New to Full) it is waxing. When it is getting smaller (phases Full to New) it is waning. For month, on the 2nd. You might guess, then, that example, if today the Moon were a waxing crescent, then tomorrow the crescent shape February has no Full would continue to grow larger, approaching first quarter. After first quarter, the Moon Moon in years when Jan- would be a waxing gibbous, and continue growing until it reached full. The Moon would uary and March have two then begin to shrink, becoming first a waning gibbous and eventually reaching third quarter. Full Moons each. This Following third quarter it becomes a waning crescent, and continues to shrink until it be- happens, on average, comes invisible at new Moon. about three times each Just in case you can't remember all of this, there are a few handy ways to recognize century. whether the Moon is growing or shrinking. A crescent moon which looks like a "C" is shrink- ing (C for collapsing!). If it looks like a "D", then it is growing. This is true for a gibbous Moon The 31-days months (especially October, Au- as well, but it's a bit trickier to picture. If the edge of the Moon (the real edge of the Moon, gust and July) have the not the edge of night on the moon) is curved like a "C", the gibbous Moon is shrinking. An- most Blue Moons. other way to think of it is that the Moon always grows or shrinks from the right to the left. 1.) New Moon - This time you can't see the moon at all! 2.) Waxing Crescent - The term waxing in this case means to get larger. The part we are talking about getting larger is the lit up part of the moon. During this time just a small part which is less than one half of the moon is lit up. 3.) First Quarter - One full half of the moon is lit up. 4.) Waxing Gibbous - Again waxing is referred to as slowly getting bigger. Each day the lit part gets bigger and bigger. 5.) Full Moon - This is the day you are grumpy. Just kid- ding! When the moon is on the opposite side of the Earth than the sun, this is when the full moon comes out to play. This is the only phase that a lunar eclipse is pos- sible. 6.) Waning Gibbous - Waning means that the moons is first quarter moon phase. slowly getting smaller. You can see that the lit part is 8.) Waning Crescent - Once again, waning means the lit shrinking in size. part of the moon is shrinking in size. Each day a little 7.) Last Quarter - This is no different view than the first more is less seen until the new moon phase hits again. quarter moon phase. Instead the light is slowly getting After completing the 8 moon phases, it goes through the smaller as compared to slowly getting bigger after the cycle continuously until the end of the world! (Oana Jurj)
The Moon Calendar PAGE 5 Moon Phases Calendar 2017 There were no Blue Moons during this year (2017). The next super- moon will be on May 25, 2017. What is a Black Moon? We had never heard the term Black Moon until early 2014. It Once in a Blue Moon doesn’t come from "Once in a Blue Moon ..." is a com- astronomy, or Blood Moon is sometimes mon way of saying not very often, skylore, either. In- used to describe 4 total lunar but what exactly is a Blue Moon? stead, according to eclipses that occur in a row. In recent years, people have been The term may have also David Harper, the using the name Blue Moon for the second of two come from the reddish glow a full Moon can term comes from full moons in a single calendar month. An older take on when the Earth casts its shadow on it Wiccan culture. It’s definition says a Blue Moon is the third of four full and eclipses it. Total lunar eclipses do not occur the name for the moons in a single season. Someday, you might see often – only about 1 in 3 lunar eclipses are total, second of two new an actual blue-colored moon. The term once in a and about 4 to 5 total eclipses can be seen from moons in one calen- blue moon used to mean something rare. Now any single location on Earth in a decade. Every dar month. January that the rules for naming Blue Moons include sev- once in a while, however, 4 total lunar eclipses 2014, for example, eral different possibilities, Blue Moons are pretty happen in a row. This rare occurrence is called a had two new moon lunar tetrad. The eclipses in a tetrad occur 6 supermoons, the common! The next Blue Moon (second full moon months apart with at least 6 full Moons be- second of which in one calendar month) will be on January 31, tween them. (Oana Jurj) was not only a 2018. supermoon, but a A supermoon is a new or full moon closely coinciding The Supermoon with perigee – the moon’s closest point to Earth in its Black Moon. monthly orbit. An astrologer, Richard Nolle, coined the term supermoon over 30 years ago, but now Another definition many in astronomy use it as well. What did astronomers call these moons before we called them super- for Black Moon is: moons? We called them a perigee full moon, or a perigee new moon. Perigee just means “near Earth.” the third of four According to the definition of supermoon coined by Nolle, the year 2017 has a total of four super- new moons in one moons. The first supermoon, for 2017, comes with the April 26 new moon. The new moons on May 25 season. and June 24 are also considered supermoons, according to Nolle’s definition, and that same definition dictates that the full moon of December 2017 – plus the full moons on January 2 and 31, 2018 – will be supermoons, too. (Oana Jurj)
PAGE 6 The Moon’s Map Selenography Selenography is considered to be a subdiscipline of sele- moon maps were nology, which itself is most often referred to as simply probably more ac- "lunar science." Selenography is the study of the surface and curate than earth physical features of the Moon. Historically, the principal maps at this point. concern of selenographists was the mapping and naming of Intrigued by an odd- the lunar maria, craters, mountain ranges, and other various ly shaped crater features. But, how do you map something 238,856 miles rim, in 1679 Cassini away? You can’t just send out a team of surveyors. At least, included a small you couldn’t until relatively recently. Before then, lunar drawing of a wom- cartographers (technically, selenographers) could only rely an’s face in profile. Hevelius’s Moon atlas on telescopes and their own artistic ability to draw a de- Tobias Mayer tailed portrait of the lunar face. They managed some pretty was the first to give the moon proper latitude and longitude dazzling results. and take libration into account. Mayer used his libration cal- The oldest known illustration of the Moon was found in culations in order to produce a series of incredibly accurate a passage tomb in Knowth, County Meath, Ireland. The maps of the surface of the moon during a lunar eclipse on tomb was carbon dated to 3330–2790 B.C. The idea that August 8, 1748. The first published large map of the Moon, the Moon was not perfectly smooth can be traced as far four sheets in size, was published in 1834 by Johann Heinrich back as approximately 450 BC, when Democritus believed von Mädler, who followed this up by publishing a book enti- that there were "lofty mountains and hollow valleys" on the tled, "The Universal Selenography". Moon. The next major advancements in lunar cartography came Around 1603, William Gilbert compiled the first lunar during the mid-20th-century space race between the USSR drawing based on naked-eye observations. One of the first and USA. The Soviets were up there first, in 1959, sending up widely seen images of the moon (aside from the IRL ver- Luna 1, the first man-made object to leave the Earth’s atmos- sion), the drawing at left was included by Galileo in a book phere and never return. Unfortunately, it missed its target, published in 1610. While he didn’t technically map the and accidentally became the first man-made object to orbit moon, these observations were among the first to take the Sun.Luna-2 succeeded in hitting the moon, and Luna-3 note that the moon was not a perfect smooth magic sky- sent back the first images of the far side of the moon, some- ball but a rough, irregularly surfaced rock with valleys and thing previously only wondered about. mountains and other chartable features. Between 1966 and ’68, the Americans, feeling as though The first formal attempt at mapping the moon — that is, merely looking at the moon wasn’t enough (well, they felt a one that didn’t just take note of curious craters and riveting lot of things, but you know, Cold War), launched seven indi- ridges, but attempted to define all vidual spacecraft— the Jet Propulsion Laboratory’s Surveyor features on a grid — happened only a program — to the surface of the moon to transmit photo- few decades later, in 1645. Dutch graphs and soil data, with the goal of testing the feasibility of a astronomer Michael van Langren manned landing. attempted a detailed study of the Surveyor 3, which scouted the Mare Cogitum, was close moon’s visible surface during differ- enough to the Apollo 12 landing site that astronauts were ent phases. Two years later, Van able to amble over to it and remove parts; the camera, which Langren’s Polish rival, Johannes He- sent back over 6,000 images of the surrounding area, is now velius, published a more complete on display at the Smithsonian Air & Space museum. description of the moon in the form Galileo’s drawing of a lunar atlas. The two years of NASA's Lunar Reconnaissance Orbiter science team re- extra effort was worth it: Hevelius leased the highest resolution near-global topographic map of is remembered as the father of lunar topography. the moon ever created. This new topographic map shows the surface shape and features over nearly the entire moon with The modern scheme of lunar nomenclature was devised a pixel scale close to 328 feet. by Giambattista Riccioli. In particular he argued against the views espoused by Galileo and Copernicus that favored a Although the moon is Earth's closest neighbor, knowledge heliocentric model with perfectly circular orbits. However of its morphology is still limited. Due to the limitations of the only significant aspect of the work to survive to the previous missions, a global map of the moon's topography at present period is Riccioli's system of lunar nomenclature, high resolution has not existed until now. With LRO's Wide published in 1651. Angle Camera and the Lunar Orbiter Laser Altimeter instru- ment, scientists can now accurately portray the shape of the The 17th century was a great time to be alive if you entire moon at high resolution. were interested in staring at the moon - truth be told,
The Moon’s Map PAGE 7 The Dark Side of the Moon You probably know we only see one side of the Moon from sounds around Saturn as well, in 2002. Two months after the Earth. But for the majority of human history, we had no Apollo 10 heard the sounds, Michael Collins, the Apollo 11 idea what the far side looked like. The far side of the Moon is astronaut who stayed in the moon’s orbit while Neil Arm- the hemisphere of the Moon that always faces away from strong and Buzz Aldrin touched down on its surface, heard Earth. The far side's terrain is rugged, with a multitude of im- them too. pact craters and relatively few flat lunar maria. It has one of You would think that the far side of the Moon would look the largest craters in the Solar System, the South Pole–Aitken like the near side, but check out the two hemispheres… basin. Although both sides of the moon experience two weeks They’re totally different. The near side of the has huge re- of sunlight followed by two weeks of night, the far side is also gions of ancient lava flows, called maria. While the far side is referred to as the dark side of the Moon,originally in the sense almost entirely covered in crater impacts. Planetary geolo- of "unknown" rather than lack of light. gists aren’t sure, but it’s possible that the Earth used to have The first spacecraft to image the far side of the Moon was two Moons. the Soviet Luna 3 probe in 1959, which returned 18 usable Just like half of the Earth is always in darkness, and half of images to scientists. And then in 1965, the Soviet Zond 3 trans- every other large object in the Solar System. There’s no per- mitted another 25 pictures of higher quality that gave much manent “dark side” of the Moon. The side facing towards the more detail of the surface. The first humans to actually see the Sun is lit up, and the side facing away is in shadows. There far side with their own eyes, were the crew of Apollo 8, who are, however, some spots on the Moon which are in eternal did a flyover in 1968. darkness. There are craters at the north and south poles deep “Boy, that sure is weird music.” enough that the light from the Sun never illuminates their floors. In these places, It’s possible that there are reserves of “We’re going to have to find out about that. Nobody will be- ice that future space colonies could use for their supplies of lieve us.” water, air, and even rocket fuel. “Yes. It’s a whistling, you know, like an outer-space-type The far side of the Moon is naturally shielded from the thing.” Earth’s radio transmissions, so it makes an ideal spot to lo- In 1969, the Apollo 10 astronauts orbited the moon as a test cate a sensitive radio observatory. -run for the Apollo 11 moon landing two months later. While China’s space agency has announced plans to become the they flew around the far side of the moon—which put them first to land on the far side of the moon, which is always hid- out of radio contact with Earth for roughly an hour—they den from us – a tricky task given that it is not possible to com- heard some strange sounds that they could not immediately municate directly with Earth from there. But if successful, the identify. Space makes “sounds” all the time—usually due to mission could shed light on many things we don’t know about charged particles interacting with a planet’s magnetic field. In the moon, such as what is going on deep beneath its thick 1979, NASA’s Voyager spacecraft picked up a noise near Jupi- crust. Chang’e 4, scheduled for launch in late 2018, is the next ter (video) that sounds a lot like what the Apollo 10 astronauts phase of China’s exploration of the moon. It builds on the heard orbiting the moon. The Cassini spacecraft recorded success of its Chang’e 3 lander, which touched down on the moon in December 2013 and successfully deployed a robotic rover named Yutu. Although Yutu found itself unable to move after its second night, it continued to provide data, leading to the discovery of a new type of moon rock. Other proposed missions to the far side of the moon – such as the crowd- funded Lunar Mission One, the Russian and European Space Agency jointly-planned Luna 27, and maybe an independent ESA lander, too – are aiming at the fringes of SPA basin at the moon’s south pole, from where the Earth stays in view as it tracks around the horizon. If the Chinese make a success of this and Chang’e 5, their next logical step will be to send as- tronauts to the moon. And it seems that in this they will be in a race with the European Space Agency rather than with NASA, which currently has its sights set on sending humans to Mars instead.
PAGE 8 The Moon and Human Life What if the Earth had no Moon? Our nearest neighboring body in the cos- Moon, the same way the Moon is locked preventing catastrophic shifts in our mos has a profound effect on us. It’s helped to us and always shows us the same face. rotational axis. It’s probable that not only shape our evolution, biologically, but Instead of 24 hours, a day would last for sometimes, we’d be like the planet has shaped the entire evolution of our planet. some 47 current Earth days. (In reality, Mercury, orbiting in the same plane as It’s totally reasonable and conceivable that the Sun will end its life long before that our rotation, and having practically no life would have sprouted and thrived on happens, so no worries there.) seasons due to our axial tilt. At other Earth even without the Moon, but things times, we’d possibly be as extreme as But in the meanwhile, we can use what would be significantly different in detail. Some Uranus, rotating on our side like a we know to extrapolate backwards in of them would be obvious, some would be a barrel, having the most extreme sea- time, and we find that in order to get a little more subtle, but there would be a great sons imaginable! 24 hour day today, the Earth had to have many impacts that we’d notice if we knew to been spinning much faster in the past: Earth is special, though, because look for them. about three-to-four times as fast more we have an external force to stabilize Without the Sun, Moon and Earth, there than four billion years ago! If we didn’t us against that sort of behavior. Know would be no eclipses. The Sun is constantly have a Moon — if we never had our what’s responsible? shining on Earth, casting a shadow for over a Moon — the day would be much, much Most people know that the moon's million miles (and over a million kilometers) shorter than it is today, and our planet gravitational influence has an effect on in its wake. Yet without our Moon — just a would have a larger equatorial bulge, the tides on Earth, but some scien- few hundred thousand miles (or kilometers) much more flattened poles, and over tists also believe that the presence of away — there’d be no object that would pass 1,000 days in a year! the moon played an important role in through the Earth’s shadow; there’d be no making Earth habitable to begin lunar eclipses. with. The interplay between the As it stands, tides from the Sun are only Earth and the moon mirrors about 40% as strong as tides from the Moon. events that occurred throughout When the Sun and Moon line up in either the the early solar system, as a Mars- “new” or “full” Moon phases, we get spring sized object may have hit the tides, 140% as large as a typical tide, and Earth, sending some of the mantle when they’re at right angles, we get neap into orbit that soon cooled into tides, only 60% as strong as a standard tide. the moon. Over time, the rela- But without any Moon at all, our tide pat- tionship between the Earth and terns would be much simpler, and only the the moon may well have assisted Sun would contribute anything substantial. So the advent of life. our tides would only be about 40% as large The flow of the oceanic tides as a typical tide is today. Not the biggest of If the Earth had no Moon then our facilitates the movement of heat from deals, but definitely something we’d notice. axial tilt would vary tremendously over the equator north and south to the If the Earth had no Moon then night would time! You probably learned that the poles. Without those tides, it is possi- have been much darker than we're used to, Earth rotates on its axis, tilted at about ble that climate changes ranging from and a day on Earth would be much, much 23.5 degrees relative to its orbital plane ice ages to glacial periods would not shorter; only about 6-to-8 hours, meaning around the Sun. This is true! But did you be as extreme. As they happened, the there’d be between about 1,100-1,400 days ever stop to think what keeps the Earth glacial phases may have helped speed in a year! from changing the tilt of its axis-of- up migrations of plant and animal rotation? The same way a spinning top species that caused life to spread. Our 24-hour-days may seem like they not only precesses but also exhibits more don’t change from one year to the next. In Tidal heat transfer may also have complicated motion over time (some of reality, the change is so tiny that it took cen- made climatic fluctuations less ex- which you may know as nutation), an turies to perceive, but the Earth’s rotation treme, so research is still underway entire planet can do this, too. Mars is a slows down ever so slightly over time, thanks to determine what actually took place perfect example: currently tilted at about to the tidal friction provided by the Moon. over lengthy periods of time. If life 24 degrees relative to the Sun, we know The slow-down is very, very slow (on the came into being around hydrothermal that its axial tilt varies from about 15 order of microseconds-per-year), but over vents deep in the oceans, then the degrees to about 35 degrees over time! millions and even billions of years, it adds up! role of the tides was likely minor, but That’s right, the Moon! Thanks to our if life began in the tidal waters, then In about 4 million years, we’ll no longer Moon, our axis stays tilted between 23 need leap years to keep our calendars on the moon's role would have been and 26 degrees over time, even over track. If the Sun would live an infinite amount much more significant.. hundreds of millions of years! But with- of time, the Earth would eventually slow (Karina Bleicziffer) out our Moon, there would be nothing down and become tidally locked to the
The Moon and Human Life PAGE 9 What Happen if Earth Had More than One Moon? We Never Imagined Earth having More than one Moon. But regular as it is now. What will it be, if Earth had many moons? This picture may be Human life would easy for our imagination, but the effects of adding moons will undoubtedly take a drastically affect the climatic condition, biosphere and life sup- nasty hit, but once the porting system of our earth in unimaginable ways. newer moons settle The Moon exerts a gravitational pull on Earth that causes into their respective the creation of tides in huge bodies of water; in fact, the gravi- places around Earth, tational pull of the Moon causes oceans to bulge outwards in things would begin to the direction of the pull (did you know that?). Although the settle down. We gravitational attraction between the Sun and Earth is 177 would certainly have times stronger than the Moon and Earth, when it comes to more solar and lunar creating tides in our oceans, the Moon dominates the Sun. eclipses than we expe- Therefore, all the big tides that you see roaring in the distance rience now. Nights from the beach are primarily caused by our single Moon. Can would also be much more illuminated than what we experi- you imagine what would happen to the scale of tides if there ence today, since presently, there’s only one moon to reflect were more than one moon? the Sun’s light to Earth. We would also have fewer hours of darkness. Neil Comins, an astronomer and a Physics professor at the University of Maine, has written an entire book on the topic However, this is not necessarily a good thing, at least not ‘What if Earth Had Two Moons?’ In his book, he claims that a for star-gazers and astronomers, because having so much second Moon (he calls it ‘Lluna’) would settle in an orbit half- illumination at night would make the observation of stars way between the Moon and Earth. Its gravitational pull on much more difficult. Earth would be high enough to create tides almost eight times Since the difference between high tides and low tides higher than those we see today. Tidal waves of such magni- would be thousands of feet, living along shorelines would tude would cause natural disasters like tsunamis, earthquakes also be almost impossible. This would significantly shrink the and extremely strong volcanic activity. Needless to say, all of habitable area on Earth, resulting in a tremendous rise in the this would cause destruction of epic proportions, resulting in population of inland urban areas. With such unpredictable mass extinctions for a large number of living things. waters, using waterways as a means of transport would be The Presence of More than one moon will affect the Tidal nothing short of throwing yourself into an impromptu duel Waves on Massive Water Bodies on the Earth Surface. The with a Gladiator! There would be many other indirect and far tidal effect of the moon only significantly affects the largest -reaching effects on Earth due to the presence of multiple bodies of water, such as the major oceans. The gravity of the moons. So as it turns out, it’s good that we have only one moon pulls the water in the oceans toward it. As the Earth moon, and it’s even better that it’s going to stay that way in rotates, the bulge shifts through the different regions of the the near future. globe. Tides appear on both sides of the Earth because of the Time on the Earth will be affected by the presence or ab- pull of the sun. The Presence of More than one moon may sence of Moon(s). Moon Affects the Time on Earth and the create waves who may rise to several meters and may cause Moon is Constantly Shifting Away From The Earth Surface. Massive Tsunami. The difference between high and low tides The Total Duration of Earth Day was not 24 hours from the would be measured in thousands of feet. Proximity to the wa- beginning of Earth. At the Very Early Centuries, the Earth Day ter is a necessity for sewage draining and transport of goods, was incredibly Short – just five hours long. By the time of the but with higher tides and stronger erosion, humans would Jurassic period, when dinosaurs roamed the Earth, a day had have to develop different ways of using the oceans for transfer lengthened to about 22.5 hours. This is increased to 24 hours and travel. The habitable area of Earth, then, would be much at present and it may reach a higher value after few more smaller. million centuries, as moon continue to drift away from us. However, it also depends on the moons’ respective positions The Presence of Moon’s Gravity Strongly Affects the duration relative to Earth. The amplitude of waves would either be larg- of The Earth Day. The Presence of More than One Moon will er or smaller, since having so many moons would either add to increase the gravity, thus it will heavily Reduce the Earth’s or compensate for each other’s effects on Earth’s tides. Also, Day Duration, as a Result Earth might become a difficult place the cycle of tides (e.g., we have two high tides and two low for Survival. (Ivan Nikolett) tides in the span of 24 hours on our planet) would not be as
PAGE 10 Moon in Romanian culture The Moon in Romanian folklore The Moon has always been associated with magic, folklore, superstitious beliefs and ancient rituals. In Romanian folklore, the Moon, the largest star on the bright sky has always been wrapped in mystery. Always appearing at night when all the rest are sleeping and dreaming, is seen as the protector of births, the harvest patron, but it is also held responsible for the sickest crimes, accidents, paranoia and depression. More than 40 years since man first walked on the moon, in Romanian culture and not only, there are people who believe that in reality, the man never set foot on the moon. Along with the Sun, it fascinated all civilizations from the oldest of times to this day. The Moon, the Sun, but also the stars are perceived as essential elements of our cosmic space and that is why we find them in many Romanian ballads, poetry, legends and tales. A well-known and very respected Romanian ethnologist believes that. In Romanian folklore, the Sun and the Moon are characters present in all species, from songs and games for children, chants, carols, ballads, songs of harvest, stories and fairy tales. "An interesting fact is that the presence of the Sun. is, with, extremely rare exceptions, a beneficial one to the people: "the sun is treated with the greatest respect, is considered the face of God." (John Moanta). The cases where the Sun is seen as Evil are rare ("black sun"). In all cases the Sun is a male, the "brother", a man's best friend, who helps him in all the crucial moments of life. “The Moon on the other hand is always a woman, young and beautiful. In many ballads the Moon is a synonymous character with Ileana Sânziana and Ileana Cosânzeana. Numerous references to the Sun and Moon are found in the ballad. In Romanian folklore, ballad, present in many volumes of Romanian authors, is very often framed in incest theme. Legend tells us that the Sun was in love with his sister Ileana Cosânzeana who refused to marry with her brother. Sent to God, the Sun must pass the test of Heaven and Hell. Firm in his incestuous desire the Sun is determined to go all the way and refuse to accept an alter- native. The wedding takes place, but Ileana Cosânzeana is raised by a divine hand and cast into the sea in the form of a golden fish. How- ever, the Sun refuses to give up and calls the local fishermen for help.. To prevent the marriage with a person of the same blood and all the misfortunes that might result from this, saints throw the golden fish in the sky, receiving the name Moon. The ballad ends with a moral and final sentence of divinity on the two brothers: Forever you will be apart! (Pentek Iulia) Romanian Werewolves Werewolves stories have been around in Eastern Europe cul- from the middle of November to Christmas Day is a period of ture and not only much longer than those with vampires and fasting and abstinence. Failing to do so will bring animal zombies. Its Romanian brother called “vârcolac” more recently characteristics to the new born child. The baby will be a curs- replaced by the term “pricolici” was in the past a vampire or an ed child with a wolf head or wolf ears and will be unlucky for unbaptized child. Their appearance is universally accepted: a the rest of his life. There are hundreds of versions of these part-man, part-wolf creature that preys on humans on the nights songs collected from all over the country: Oltenia, Moldavia, with full moon. In this situation the moon plays a double role. On Basarabia and Transylvania, the home of Count Dracula. Deep one hand it is always the triggering factor, on the other hand it in the Carpathian Mountains, the idea of a forest full of were- can be seen as a victim, because werewolves, in many tales, wolves flourished. Many of the local villagers are convinced of want to devour the moon, because they love the darkness. their existence and even perform rituals the help them kill the werewolves. The most efficient ways to kill such an evil In Romania, during winter holidays, from Christmas to New spirited animal are crucifixes and silver bullets. Year`s Eve, groups of young unmarried men parade through villages, wearing traditional costumes and masks representing Romanian werewolf legends present, according to Harry different animals, people and devils, from sunset to dawn singing Senn “stories of wives attacked by husbands, of villagers what ethnologist call ritual hymns (colinde). They are often ac- forced to defend themselves against menacing were-pigs, but companied by musicians playing “capra”(the goat), “ursu” (the also villagers who continue to reside in the village even after bear), “căluțu” (the little horse) and “barza” (the stork). their periodic wolf metamorphosis. Solitary wolves, further- more, fed by travelers camping in the forest, subsequently These young unmar- richly reward their benefactors for leaders, likewise patron ried men who joined saints of wolves, Peter and Andrew, direct and nurture their together at Christmas animal charges. Romanian villages offer us, in conclusion, a gathered first on larger mythological cosmology and context of folk traditions St.Nicholas` Day, on in which werewolves and vampires find a more natural December 6 to select place” (Senn Harry, Romanian Werewolves, Seasons, Rituals, their leaders and plan Cylces,Folklore vol.93:2, 1982). their activities. To Christians, the period (Corlan Alex)
Moon in other cultures PAGE 11 The Man in the Moon The "Man in the Moon" illusion, familiar to massive asteroid crash. The latest re- see today as dark spots on the near side various cultures around the world, was created search, published in the journal Nature, of the moon. These are the features that by powerful asteroid impacts that rocked the now suggests it may have been caused by have inspired the idea of a man in the satellite billions of years ago, a new study sug- a large plume of magma. Using data ob- moon. Ms Zuber, who is also Grail's prin- gests. The study, performed by Laramie Potts tained from Nasa's Grail (Gravity Recovery cipal investigator, said: "A lot of things in and Ralph von Frese of Ohio State University, and Interior Laboratory) mission, the re- science are really complicated, but I've reveals that ancient lunar impacts played a search team from MIT, the Colorado always loved to answer simple ques- much larger role in shaping the Moon's surface School of Mines and other institutions tions. "How many people have looked up than scientists had previously thought. It may have created a high-resolution map of the at the moon and wondered what pro- also help explain the origins of two mysterious Procellarum. They found that its border is duced the pattern we see - let me tell bulges on the Moon's surface. not circular, but polygonal and made up of you, I've wanted to solve that one!" sharp angles that could not have been For millennia, people have looked up at the The map was created using twin probes created by a massive asteroid. They be- full Moon and sworn that they could see some- that orbited the moon from January to lieve the angular outline was produced by thing up there. Depending on the culture, it's December 2012 and was used to deter- anything from a face to a dragon. But why is mine where the lunar crust thickens and anything there in the first place? The Man in thins. They found that the rim of the the Moon - which we'll use as the collective Procellarum region is composed of edges name for everything cultures have seen on the made up of 120-degree angles. face of the Moon, which also includes a hu- An asteroid strike would create circu- man figure, a rabbit, and a buffalo, among lar or elliptical craters and not these others - is pretty weak, as optical illusions go. angular shapes, the team suggests. The mystery behind the 1,800-mile-wide sec- tion of the moon has been a long-running They then went on to explore a theory puzzle among scientists - who previously that some time after the moon formed blamed it on an asteroid crash. The famous and cooled, a large plume of molten giant tension cracks in the moon's crust as material rose from the lunar interior, flattened image across the moon's surface - it cooled around an upwelling plume of around where the Procellarum region is dubbed the Man in the Moon - may have been hot material from the deep interior. Maria today. The steep difference in tempera- created by a large plume of magma deep inside Zuber, MIT's vice president for research, ture between the magma plume and the the moon coming up towards the surface. The says that as cracks occurred, they formed surrounding crust caused the surface to mystery behind the 1,800-mile-wide section of a "plumbing system" in the moon's crust contract over time, creating a pattern of the moon's Procellarum basin has been a long- through which magma could meander to fractures that provided a chance for running puzzle among scientists who have pre- the surface. Magma eventually filled the molten material to rise to the surface. viously claimed it may have been caused after a region's smaller basins, creating what we Further tests, created by modelling the region's gravitational signal, matched The Tales of the Man in the Moon data recorded by Grail and backs the When some people look at the moon they claim they can see the face or even the whole idea that the Procellarum was caused by body of a human. The idea of a man on the moon goes back to the Middle Ages, with the a magma plume and not an asteroid. earliest reference coming from the English scholar Alexander Neckham (1157 – 1217). In his book De Naturis Rerum he has a small section called ‘About the mark on the moon’ But the mystery of the Man in the where he writes: Don’t you know that which the common crowd calls “The peasant in the Moon has still not been completely moon, who carries thorns’? Therefore one says commonly: The peasant in the moon, solved despite this latest theory, accord- whom a (certain) bundle weighs down/Illustrates through the thorns that stealing is never ing to Ms Zuber. She said: "How such a profitable.” A few other late medieval English stories also have a similar story where the plume arose remains a mystery. It could man in the moon was some peasant who gets caught stealing thorns to help him build a be due to radioactive decay of heat- hedge (every villager would be responsible for helping build and maintain hedges to keep producing elements in the deep interior. livestock from roaming into planted fields – and they would place thorns on the hedges so "Or, conceivably, a very early large im- the animals wouldn’t be able to eat that either). A medieval German tale explains there pact triggered the plume. "But in the are two people on the moon – a man and a woman. The man has been banished there latter case, all evidence for such an im- because he had placed thorns on the path to a church in order to prevent people from pact has been completely erased. going to Sunday mass. Meanwhile, the woman is there because she made butter on Sun- "People who thought that all this volcan- day. To add to their punishment the man carries his bundle of thorns on his back, while ism was related to a gigantic impact the woman carries a butter-tub. Another medieval legend says the man in the moon is need to go back and think some more Cain, who as punishment for the murder of his brother Abel is exiled to the moon with about that." (Nagy Bianka) some twigs. (Nagy Bianka)
PAGE 12 Travelling to the Moon Apollo Missions - "That's one small step for a man. One giant leap for mankind." The man’s first step on the moon orbited the moon for ten revolutions (20 hours 7 minutes) before return- turned 43 years. Uncoincidently, may- ing to the earth and a controlled reentry into the Pacific Ocean. be, NASA announced recently that its Apollo 9 was the first flight test of the complete lunar landing mission . Lunar Reconaissance Orbiter (LRO) The crew consisted of James A. McDivitt, David Randolph Scott, and Rus- has captured conclusive images to sell L. Schweickart. The first Apollo spacecraft to be named, Gumdrop show that almost all American flags (CSM) and Spider (LM) were launched into the earth's orbit on March 3, hung by astronauts on the moon are 1969. During ten days of operations, the crew demonstrated all Apollo still in their rightful place, undisturbed. mission maneuvers. Remaining in the earth's orbit, the crew simulated a Maybe only withered. The aim of the Apollo programme was to lunar landing with the LM and conducted the first actual LM rendezvous land the first person on the Moon. However, when the program with the CSM. The crew also practiced backup safety maneuvers, including was announced, in 1961, only two people had actually been in space. a procedure in which astronauts used the LM as a lifeboat in case the com- Scientists were faced with a daunting task - to construct a rocket mand module was rendered inoperable or uninhabitable. This procedure powerful enough to reach the Moon and a spacecraft that could was subsequently used to recover Apollo 13. travel there and back. Built for the Apollo missions, the giant Saturn Apollo 10 was a dress rehearsal for a lunar landing mission and was con- V rocket was one of the most powerful rockets ever built. It was ducted in lunar orbit, but it excluded the actual landing. Launched on May extremely successful, with 13 perfect launches and no failures, even 18, 1969, the spacecraft Charlie Brown (CSM) and Snoopy (LM) spent over during its test flights. Saturn V carried the Apollo craft into Earth two days and 31 revolutions in lunar orbit. The crew of Thomas P. Staf- orbit; then the third and final stage fired again to provide an extra ford, John W. Young, and Eugene Andrew Cernan conducted all propulsive boost to place it on the correct trajectory for the Moon. maneuvers required for a lunar landing mission. During lunar orbit, Staf- Three main components made up the Apollo spacecraft. The com- ford and Cernan descended in the LM to within 14 km (18 mi) of the lunar mand module (CM) held supplies and contained the crew's quarters, surface before completing the first lunar orbit rendezvous with the CSM. which had just enough room for the astronauts to move around in. This eight-day mission was recovered in the Pacific Ocean. Attached to the CM was the service module (SM), which housed the Apollo 11 was the first lunar-landing mission. Launched on July 16, 1969, craft's main engine. It supplied electrical power and controlled the the crew of Neil A. Armstrong, Edwin E. Aldrin, Jr., and Michael Collins crew's life support system. On returning to Earth, the SM was jetti- flew the spacecraft Columbia (CSM) and Eagle (LM). On July 20, 1969, soned, the CM, with the astronauts inside returned to Earth. The Armstrong and Aldrin landed the Eagle at the relatively flat and unob- third part of the craft was the lunar module. The Apollo Lunar Mod- structed Tranquillity site on the moon, while Collins remained in the CSM. ule (LM) carried the astronauts onto the Moon's surface and was The LM spent 21 hours 36 minutes on the lunar surface, and the crew home to them during their stay. There were no seats and there was spent 2 hours 31 minutes outside the LM in a local area excursion on foot only just enough room for two astronauts to stand. Once on the to a distance of approximately 50 m (160 ft) from Tranquillity Base. Arm- Moon, the astronauts could leave the LM to explore the surface. strong and Aldrin evaluated the capability of working on the lunar surface, On January 27, 1967, the launch crew and flight crew of the first established a small scientific station, and collected 21 kg (46 lb) of lunar Apollo mission were conducting a simulated countdown to test rocks and soil. Using the descent stage of the LM as a launching platform, the operations . The spacecraft was ready for a simulated launch, the ascent stage of the LM took off from the moon's surface to rendezvous with hatch locked, power on, and an internal atmosphere of pure and dock with the CSM. The spacecraft departed lunar orbit over two days oxygen. The crew of Virgil I. Grissom, Edward H. White II, and after arrival. This eight-day mission landed and was recovered safely in the Roger B. Chaffee were in their space suits and performing the nor- Pacific Ocean. As a precautionary measure, the astronauts were quaran- mal sequence of prelaunch activities. At about 6:30pm, after over tined for 14 days. five hours of delays and problems, a spark inside the spacecraft Apollo 12 was the second lunar landing mission and the first mission to ignited flammable material and instantly engulfed the closed com- make a pinpoint landing on the moon. Launched on November 14, 1969, partment in flames. By the time the hatch was pried away more than the crew of Pete Conrad, Richard Francis Gordon, Jr., and Alan LaVern five minutes later, the crew had died from asphyxiation. The precise Bean flew the spacecraft Yankee Clipper (CSM) and Intrepid (LM). Conrad source of the spark and fire was never determined. As a result of and Bean landed the LM on the southeastern Oceanus Procellarum region the fire, many changes were made to the design, manufacturing, test, of the moon within 200 m (660 ft) of their target. The crew spent 31 and checkout procedures of the vehicles and the management of the hours 31 minutes on the lunar surface conducting two excursions for a entire Apollo Program. Many of these changes were tested in the total of 7 hours 45 minutes. The first excursion included an inspection of unpiloted Apollo missions 4, 5, and 6. the Surveyor 3 lunar probe, which had landed on the lunar surface years Apollo 7 was the first manned earth orbit flight test of the CSM. earlier. Several components were extracted from the probe for engineer- This ten-day mission was launched on October 11, 1968. On board ing analysis. Conrad and Bean conducted geological observations, and were Walter M. Shirra, Donn F. Eisle, and R. Walter Cunningham. collected 34 kg (75 lb) of lunar rocks and soil. They departed lunar orbit While orbiting the earth, the crew practiced maneuvers that would just under four days after arrival. This ten-day mission landed without be used in a lunar mission. After exiting orbit and re-entering the incident in the Pacific Ocean. atmosphere, the capsule and crew were safely recovered in the Apollo 13 was launched on April 11, 1970, as the third planned lunar Atlantic Ocean. landing mission. The crew of James A. Lovell, Jr., John L. Swigert, Jr., and Apollo 8 was launched on December 21, 1968, and was the first Fred Wallace Haise, Jr., flew the spacecraft Odyssey (CSM) and Aquarius manned mission to achieve lunar orbit. The crew of this six-day (LM). Two days after launch, as Apollo 13 approached the moon to begin mission, Frank Borman, James A. Lovell, Jr., and William A. Anders, lunar operations, an explosion occurred that caused the service module of conducted a complete test of the CSM flight profile for lunar mis- the CSM to lose its oxygen, electrical power, and other systems, including sions. The CSM entered lunar orbit on December 24, 1968, and its capability to perform an abort maneuver for a direct return to the
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