THE FAR SIDE OF
THE MOON THE UNKNOWN FACTS OF OUR ONLY SATELLITE
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MOON ENVIRONMENT
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THE FAR SIDE OF
THE MOON
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Š 2015 by Phaidon Books Images All right reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means, including information storage and retrieval systems, without permission in writing from the publisher, except by reviewers, who may quote brief passages in a review. Scanning, uploading, and electronic distribution of this book or the facilitation of the same without the permission of the publisher is prohibited. Please purchase only authorized editions, and do not participate in or encourage electronic piracy of copytighted materials. Your support of the author’s rights is appreciated. ISBN 978-1-61058-410-4
Dedicated to Neil Armstrong and Frank Drake
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01 16 - 21
02 24 - 31
MOON ENVIRONMENT This chapter will take you into the Moon closely and to learn more details about the Moon.
MOON SHADOWAS The Moon Phases nad Moon Eclipse.Two different Moon’s shadows that people has been misunderstood for a long time.
03 34 - 39
MOON ORBIT Earth and the Moon orbit about their barycentre which lies about 4600 km from Earth’s center about three quarters of the radius of Earth.
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MYTH & MISCONCEPTIONS This chapter will take you into the Moon closely and to learn the misconceptions of the Moon.
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MOON ENVIRONMENT
Introduction THE MOON
This book is about Earth’s natural satellite. The Moon is Earth’s only natural satellite. It is one of the largest natural satellites in the Solar System, and, among planetary satellites, the largest relative to the size of the planet it orbits.It is the second-densest satellite among those whose densities are known after Jupiter’s satellite Io. The Moon is thought to have formed approximately 4.5 billion years ago, not long after Earth. There are several hypotheses for its origin; the most widely accepted explanation is that the Moon formed from the debris left over after a giant impact between Earth and a Mars-sized body called Theia.The Moon is in rotation with Earth, always showing the same face with its near side marked by dark volcanic maria that fill between the bright ancient crustal highlands and the prominent impact craters. It is the second-brightest regularly visible celestial object in Earth’s sky after the Sun, as measured by illuminance on Earth’s surface. Although it can appear a very bright white, its surface is actually dark, with a reflectance just slightly higher than that of worn asphalt. Its prominence in the sky and its regular cycle of phases have, since ancient times, made the Moon an important cultural influence on language, calendars, art, and mythology.
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MOON ENVIRONMENT
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MOON ENVIRONMENT
This chapter will take you into the moon closely and to learn more details about the moon.
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MOON ENVIRONMENT
LESS GRAVITY ON THE MOON Your weight on the moon is a function of the moon’s gravity. First, we know that gravity is a force that attracts all physical objects towards each other but why this happens is largely unknown. Second, the greater the mass of an object, the stronger the force of gravity.
The moon is 1/4 the size of Earth, so the moon’s gravity is much less than the earth’s gravity, 83.3% less to be exact. Finally, weight is a measure of the gravitational between two objects. So of course you would weigh much less on the moon. Imagine how far you could jump on the moon. The Apollo astronauts apparently had fun.
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MOON ENVIRONMENT
TOXIC DUST SILLICA
Lunar dust is the fine fraction of the regolith found on the surface of the Moon. Its properties can differ significantly from those of terrestrial soil. The physical properties of lunar soil are primarily the result of mechanical disintegration of basaltic and anorthositic rock, caused by continuous meteoric impact and bombardment by interstellar charged atomic particles over billions of years. The process is largely one of mechanical weathering in which the particles are ground to finer and finer size over time. This situation contrasts fundamentally to terrestrial soil formation, mediated by the presence of molecular oxygen, humidity, atmospheric wind, and robust array of contributing biological processes. Some have argued that the term soil is not correct in reference to the Moon because on the Earth, soil is defined as having organic content, whereas the Moon has none.
The term lunar soil is often used interchangeably with “lunar regolith” but typically refers to only the finer fraction of regolith, that which is composed of grains one cm in diameter or less. Lunar dust generally connotes even finer materials than lunar soil. There is no official definition of what size fraction constitutes “dust”, some place the cutoff at less than 50 micrometres in diameter at less than 10.
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DUST COMPOSITION CLAY MICA
Over time, material is mixed both vertically and horizontally by impact processes. However, the contribution of material from great distances is relatively minor, such that the soil composition at any given location largely reflects the local bedrock composition. There are two profound differences in the chemistry of lunar regolith and soil from terrestrial materials. The first is that the Moon is very dry. As a result, those minerals with water as part of their structure such as clay, mica, amphiboles are totally absent from the Moon. The second difference is that lunar regolith and crust are chemically reduced, rather than being significantly oxidized like the Earth’s crust. In the case of the regolith, this is due in part to the constant bombardment of the lunar surface with protons from the solar wind. One consequence is that iron on the Moon is found in the metallic 0 and +2 oxidation state, whereas on Earth iron is found primarily in the +2 and +3 oxidation state.
MOON ENVIRONMENT
Lunar dust is composed of various types of particles including rock fragments, mono mineralic fragments, and various kinds of glasses including agglutinate particles and volcanic and impact spherules. The agglutinates form at the lunar surface by micrometeorite impacts that cause small-scale melting which fuses adjacent materials together with tiny specks of metallic iron embedded in each dust particle’s glassy shell.
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THE FAR SIDE OF THE MOON
MOON SHADOWS
The Moon Phases nad Moon Eclipse.Two different Moon’s shadows that people has been misunderstood for a long time.
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MOON ENVIRONMENT
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TWO DIFFERENT SHADOWS MOON PHAESE MOON ECLIPSE
One of the most beautiful things in the night sky is also the easiest to see: the Moon. Nearly everyone has seen the Moon and noticed how it changes shape each month, sometimes appearing full and bright, other times disappearing altogether. When ancient peoples of all cultures saw the Moon cycle, they did not understand it, so they invented myths. While these myths are still fun to read, humans have now walked on the Moon, flown around it, and learned what really causes its fascinating phases and occasional eclipses. Understanding the processes that cause Moon phases and eclipses can be difficult, since it requires understanding light and shadow, and being able to imagine points of view that we never experience on Earth. Many people have the misconception that the phases of the Moon are caused by the earth’s shadow across the Moon. This is not true. When the shadow of Earth moves across the Moon, we call it a lunar eclipse. When the Moon moves between Earth and the Sun, it casts a small shadow on Earth, and people inside that shadow see a solar eclipse. Both these events are rare, happening only about every 6 months.
MOON SHADOWS
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JANUARY
FEBRUARY
JUNE
MAY
MOON PHASES
JUNE
JUL
ULY
MOON SHADOWS
MARCH
APRIL
One of the most beautiful things in the night sky is also the easiest to see the Moon. Nearly everyone has seen the Moon and noticed how it changes shape each month, sometimes appearing full and bright, other times disappearing altogether. When ancient peoples of all cultures saw the Moon cycle, they did not understand it, so they invented myths. August While these myths are still fun to read, humans have now walked on the Moon, flown around it, and learned what really causes its fascinating phases and occasional eclipses.Understanding the processes that cause Moon phases and eclipses can be difficult, since it requires understanding light and shadow, and being able to imagine points of view that we never experience on Earth.
Many people have the misconception that the phases of the Moon are caused by the earth’s shadow across the Moon. This is not true. When the shadow of Earth moves across the Moon, we call it a lunar eclipse.
THE FAR SIDE OF THE MOON
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B
C
D
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F
G
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Phases of the Moon When the Moon moves between Earth and the Sun, it casts a small shadow on Earth, and people inside that shadow see a solar eclipse. Both these events are rare, happening only about every 6 months.
A New Moon
F Waning Gibbous
B
G Last Quarter
Waxing Crescent
C First Quarter D Waxing Gibbous E Full Moon
H Waning Crescnet
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Moon Eclipse
MOON SHADOWS
EARTH‘S SHADOW
A lunar eclipse occurs when the Moon passes directly behind the Earth into its umbra (shadow). This can occur only when the sun, Earth and moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can occur only the night of a full moon. The type and length of an eclipse depend upon the Moon’s location relative to its orbital nodes. A total lunar eclipse has the direct sunlight completely blocked by the earth’s shadow. The only light seen is refracted through the earth’s shadow. This light looks red for the same reason that the sunset looks red, due to rayleigh scattering of the more blue light. Because of its reddish color, a total lunar eclipse is sometimes called a blood moon. Unlike a solar eclipse, which can be viewed only from a certain relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of the Earth.
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MOON ORBIT
.Earth and the Moon orbit about their barycentre which lies about 4600 km from Earth’s center about three quarters of the radius of Earth.
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MOON ENVIRONMENT
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MOVING AWAY LARGER ORBIT
The Moon’s orbit is indeed getting larger, at a rate of about 3.8 centimeters per year. The Moon is getting closer to the Sun, specifically, it is getting farther from the Earth, so when it’s in the part of its orbit closest to the Sun, it’s closer, but when it’s in the part of its orbit farthest from the Sun, it’s far away. The reason for the increase is that the Moon raises tides on the Earth. Because the side of the Earth that faces the Moon is closer, it feels a stronger pull of gravity than the center of the Earth. The part of the Earth facing away from the Moon feels less gravity than the center of the Earth.
MOON ORBIT
Closest 225700 Miles Farthest 252000 Miles
We call the parts that stick out tidal bulges. The actual solid body of the Earth is distorted a few centimeters, but the most noticable effect is the tides raised on the ocean.
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MOON
LO
CALLISTO
TITAN
GANYMEDE
MOON ORBIT
A moon is a natural satellite rotating around a planet. While moons vary in size, each moon is much smaller than its planet. There are 176 known natural moons orbiting planets in our Solar System. Moons orbit the full-size planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus.
5TH LARGEST SATELLITE IN THE SOLAR SYSTEM
The Moon is Earth’s only natural satellite. Our planet’s trusty companion is an airless, silent world without any signs of life. Because of its small size, the Moon’s force of attraction is too weak to hold the gases it would need to form an atmosphere. The Moon is in synchronous rotation with Earth, always showing the same face with its near side marked by dark volcanic maria that fill between the bright ancient crustal highlands and the prominent impact craters. The Moon is a spherical rocky body, probably with a small metallic core, revolving around Earth in a slightly eccentric orbit at a mean distance of about 384,000 km. It’s diameter is 3475 km.
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MOON ENVIRONMENT
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MOON MISCONCEPTIONS
This chapter will take you into the Moon closely and to learn the misconceptions of the Moon.
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THE MOON HAS A PERMANENT DARK SIDE
Most junior high school students know that the moon presents only one face or side to the Earth. This is roughly true and gives rise to the idea that there is a permanently dark side of the moon, a thought immortalized in Pink Flyod’s music and elsewhere. The Earth-facing side of the moon gives rise to another misconception that many people share, namely that we see only 50% of the moon from Earth. In fact, only about 41 percent of the moon’s far side a much more accurate and preferable term than dark side is perpetually hidden from earthly observers. A diligent observer on Earth can, over time, observe about 59% of the moon’s surface.
MOON MISCONCEPTIONS
The side of the moon that is perpetually turned away from Earth is no more dark than the side we see. It is fully illuminated by the sun just as often lunar daytime, and is in shade just as often lunar night, as is the familiar Man in the Moon face we see.
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Three things canno the sun, the moon,
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ot be long hidden: , and the truth. – unknown
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Bibliography Atlas of the Lunar Terminator. 2000. book Atlas of the Other Side of the Moon. 1961. book. Elger : A Full Description And Map Of Its Principal Physical Features. 1985. book Other Side of the Moon. 1961. book. Lunar Cartographic Dossier 1973. photo Lunar Orbiter Photographic Atlas of the Near Side of the Moon by Charles J. Byrne, 2005. book.
Photographic Lunar Atlas second volume of photos from Kuiper’s new. 1960. photo.
Orthographic Atlas of the Moon from Kuiper’s new. 1960. book.
Photographic Atlas of the Moon by W. H. Pickering. 1903 Portfolio of Lunar Drawings by Harold Hill. 1991. System of Lunar Craters 1963 - 1966 The Hatfield Photographic Lunar Atlas by Jeremy Cook. 1999. book. Who’s Who in the Moon 1938. book. Times Atlas of the Moon Atlas based on LAC series 1969.
Wilkins and Moore - The moon 1961. book ALPO list of bright ray craters web. Basaltic Volcanism Study Project 1985. book Gillis and Spudis 1966. book. Lunar Cartographic Dossier 1970. photo North American Atlas by Dinsmore Alter. 1964. Orthographic Atlas of the Moon Kuiper’s new LPL 1960.
IAU Planetary Gazetteer official list of feature names. web. NASA SP-241 1971. book. Full Moon by Harold Hill. 1991. National Geographic 2007. book The Moon Moore, P. / Cross, C. A. An introduction to lunar science and lunar observing. The Once and Future Moon Spudis, Paul D. 1996. Wonders of the moon by M. G. Mead. 1873.
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PHAIDON Minion Pro Regular Berthold Akzidenz Grotesk Meduim MOAB Lasal Photo Matte 235 Adobe Indesign CC 2015 Adobe Illustrator CC 2015 This book is a student project, and has never published.
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This book is about Earth’s natural satellite, Moon. The Moon is Earth’s only natural satellite. It is one of the largest natural satellites in the Solar System, and, among planetary satellites. However, there are many unknown facts Facts everyone should know, yet most people don’t. Publisher: Phaidon Book Images Text and illustration reorganized: Copyright © 2015 by Zizhou Zhao All right reserved. Email: samuelzzz314@gmail.com