for the aliens ;)
CONTENTS
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06
10
A BRIEF HISTORY OF SPACE
MAPS OF THE CONSTELLATIONS
OUR SOLAR SYSTEM
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17
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THE SUSTAINER OF LIFE
THE MESSENGER OF THE GODS
THE SHROUDED PLANET
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THE ONE WE CALL HOME
THE GOD OF WAR AND PEACE
GLOSSARY OF SCIENTIFIC TERMS
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A BRIEF HISTORY OF SPACE
THE PLANETS AND THE SUN
For most of history, the night’s sky was illuminated with billions of stars against a velvet sky. Early groups of people would group the star together into constellations. These constellations differed from being god-like figures to a literal space dolphin, and were incorporated into many myths. Most of these ancient observations were observed with the naked eye. The Greeks provide our main source of understanding what these ancient cultures believed. They collected these observations, added their own, and produced an image of the night sky. This held the idea that the stars and planets circled the earth in orbit. Due to this, the Earth was believed to be flat. Even though many civilizations were known to travel and colonize many bodies of land showing proof that it wasn’t flat, they still believed so because of their religions.
Many portrayed gods or goddess traveling across the sky, the logical reason for day and night at the time. For the Greeks, this was Apollo in a chariot of fire. For the Norse, this was Sol, whom was chased by giant wolves as the sun set. During the 15th century BCE, a new way of thinking about the universe began to flourish in the Eastern Mediterranean. Many Greek philosophers started forming hypotheses toward the universe not being affected by Gods or religions. They started constructing many astrological models of the universe that operated solely on natural laws. This was a big step for philosophers, and by many scholars today, it considered to be the beginning of science. All of these models included two unique assumptions. Both of which were very wrong.
The first was that earth was motionless and rested at the center of the universe. This was based on the observations made of constellations and their movement around the earth. The second was that everything rotated around the earth in a circular motion. This may have been based on scientific observations, for when watching the stars for long periods of time, a circular-like motion can be seen. However, it is a fact that they believed that circles were unfathomably perfect. Thus, they wanted the universe to be unfathomably perfect. These beliefs were carried on until fifteen hundred years later. A Polish cleric named Nicklaus Copernicus introduced the idea that the earth circled the sun. Though he was right, many believed he was a fool.
ORION
CETUS
NORTHERN HEMISPHERE
TAURUS
SUMMER THROUGH FALL
ARIES
PERSEUS
ARIES The name Aries means “the ram” in Latin. It was first cataloged by the Greek astronomer Ptolemy in the 2nd century. It is the 39th largest constellation in the sky and belongs to the zodiac family. Aries is usually associated with the story of the golden fleece, as well as the telling of Aphrodite
PISCES
PISCES The name Pisces means “the fish” in Latin. It was first cataloged by Greek astronomer Ptolemy in the 2nd century. It is the 14th largest constellation in the sky and belongs to the zodiac family.
PEGASUS
CETUS This constellation was named after the sea monster from the Greek myth about Andromeda. In the myth, Andromeda was sacrificed to the monster as punishment. Cetus lives in a region of the sky that is known as the Water. DELPHINUS The name Delphinus is Latin for “the dolphin”. It represents the dolphin sent by the sea god Poseidon. It was first cataloged by Greek astronomer Ptolemy in the 2nd century.
DELPHINUS
NORTHERN HEMISPHERE
GEMINI
WINTER THROUGH SPRING
CANCER
GEMINI
URSA MAJOR LEO
The name Gemini means “the twins” in Latin. The constellation represents the twins Castor and Pollux in Greek mythology. CANCER
URSA MINOR
The name Cancer means “the crab” in Latin. It refers to the crab that Hercules kicked into the stars during the story of the 12 Labors of Heracles. VIRGO
LEO Leo represents the lion and is associated with the Nemean lion in Greek Mythology. Leo is the 12th largest constellation and belongs to the Zodiac family. URSA MAJOR
HERCULES
Its name means “the great bear” in Latin and is associated with a nymph who was turned into a bear by Hera. URSA MINOR The constellation’s name means “the smaller bear” in Latin. It contains the Little Dipper, and is also notable for marking the location of the north celestial pole.
SAGITTARIUS
SOUTHERN HEMISPHERE SUMMER THROUGH FALL
CAPRICORNUS
AQUARIUS The name Aquarius means “the water-bearer” in Latin. It is one of 12 zodiac constellations and lies in the Sea region of the sky.
PAVO AQUARIUS
CAPRICORNUS The name capricornus refers to “the goat” in Latin. One of the 12 zodiac; it is associated with the goat Amalthea. HYDRUS Latin for “the male water snake,” and is known as the lesser water snake in comparison to the Hydra constellation. It is the 61st largest constellation.
CETUS
SAGITTARIUS Depicted as a centaur holding a bow, Sagittarius is one of the twelve zodiac constellations. It is associated with Crotus, the satyr who helped the Muses on Mount Helicon. ORION Also known as the hunter, it represents the mythical hunter Orion. This constellation contains two of the brightest stars in the sky: Rigel and Betelgeuse.
ERIDANUS
ORION
LIBRA
SOUTHERN HEMISPHERE
SCORPIUS
WINTER THROUGH SPRING CENTARUS VIRGO
LIBRA This constellation’s name means “the weighing scales” in Latin, as Libra is depicted as the scales held by the Greek goddess of justice, Dike the daughter of Zeus and Greek Titaness Themis.
CARINA
VIRGO Latin for “virgin”. Virgo is the second largest constellation in the sky and is one of twelve zodiac. Associated with Dike as well, Virgo is usually depicted with angel-like wings, an ear of wheat in her left hand, and is marked by the bright star Spica.
VELA HYDRA
PUPPIS
SCORPIUS One of the twelve Zodiac, Scorpius represents the scorpion and is associated with the story of Orion in Greek mythology. Scorpius was identified with the scorpion that killed Orion. The two constellations lie opposite each other in the sky
CANIS MAJOR
HYDRA Known as the “water snake,” Hydra is the largest constellation in the sky. It represents the Lernaean Hydra from the myth of Heracles’ Twelve Labours. Hydra was a giant multi-headed creature who was half-woman and half-serpent.
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‘Solar’ is derived from the Latin word sōlāris. This pertains to the Sun, so ‘Solar System’ means the Sun System.
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THE SOLAR SYSTEM
THE PLANETS AND THE SUN
While there’s a lot we still don’t know about our world, we do know some things for sure. Our solar system is made up of eight planets, five dwarf planets, over a hundred moons, and countless asteroids and comets. All of which orbit around the sun. The four terrestrial planets are rocky and compact. Across the asteroid belt, the remaining four planets are large and gaseous.
All of these planets orbit the same plane and in the same direction. An example of this would be a race track with each lane representing a different orbital path for a planet. They each have their own path, but each remains on the same track. All terrestrial planets contain what is known as a secondary atmosphere. This means that after creation of the planet the atmosphere was formed separately.
Normally, this is due to internal volcanic activities or impacts in the surface caused by space debris. Craters from the era of early bombardment still mark the surface of the Earth’s moon and the planet Mercury. Weathering from the atmosphere and volcanic activity have erased many of these traces on Venus and Earth. In the case of Earth, involvement of humans has also played a role.
THE SUSTAINER OF LIFE WHY WE CAN’T LOOK AT THE SUN
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Every day on earth begins the same way. The sun rise over the Eastern horizon and brightens the land. Every night also begins the same way; the sun disappears over the Western horizon and darkening the land. The sun is very vital for life on our planet as we can not thrive without its light and warmth. It is very easy to forget that our “all giving source of light and power� is the most ordinary sun in our galaxy. Composed of 74.9 percent hydrogen and 23.8 percent helium, the sun rest at 865 thousand miles in diameter. It is 16 million kelvins at its core. This is equivalent to 29 million degrees Fahrenheit. Until the middle of the nineteenth century, the fact that the sun gives off energy would be an ordinary observation. However, it was around this time that we discovered the laws of conservation of energy.
This law states the energy is neither created nor destroyed. It just shifts from one form and place to another. An example would be the energy that warms your face when put in sunlight. This energy came from inside the sun. The fact that you feel the warmth means that the energy has left the sun forever. This provides an important message about the Milky Way. Every star will run out of energy. They are born, and they die like everything else. Many theories have appeared over the course of history on the source of the sun’s energy. An astronomy textbook from the late 19th century devoted several pages to calculating how long the sun could burn if it was on the best known fuel. This was anthracite coal at the time, and the answer was ten million years.
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We now know that there’s still 5.5 billion years before the sun becomes a red giant, thus closer to death.
After that, the density of matter becomes too low for collisions to obstruct the energy flow. The sun boils this material.
It wasn’t until the 1930s that a GermanAmerican physicist named Hans Bethe showed that the energy source of a star was the caused by the process known as nuclear fusion.
We can only see the outer layer known as the photosphere. Above the photosphere are the Corona, which is only visible during eclipses and the heliosphere, which extends through the solar system.
About 4.5 billion years ago the sun began burning hydrogen at the rate of more than four hundred million tons per second.
Because the sun is not solid, different parts of it rotate at different speeds. The poles make one revolution in about 35 days.
At the core of the sun, it is hot enough for nuclear reactions to occur. The radioactive zone is encountered 300 thousand miles from the core.
Equator takes about 28 days to do the same. This causes the magnetic field of the sun to constantly twist and distort.
It is here that fast moving particles from the core experience a series of collisions. This can be easily compared to that of a giant pinball machine.
This can cause phenomenons like sunspots, dark spots that move across the surface of the sun, and/or solar flares, explosions that cause a large number of particles to be thrown into outer space.
THE MESSENGER OF THE GODS WINGS AND ROCKS AND CURLY LOCKS
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The name Mercury derives from the Roman messenger of the Gods. To the Greeks, he goes by the name Hermes, which may be more familiar to some.
Taking its size and proximity to the sun into account, the Mercurian year lasts 88 earth days. While this is a short year, one day on Mercury lasts 58.5 earth days.
This planet earned its name by how it moves across the Earth’s night sky. Being visible with the naked eye, Mercury only appears in the low west after sunset or in the low east before sunrise.
This means do to the slow rotation, the surface of mercury gets extremely hot during the day, while it is extremely cold during the night. This slow rotation also eludes to Mercury having a liquid center.
Having traveled from one edge of the sky to the other, this appearance of the planet was adopted in mythology as the messenger running between tasks.
There is not seasonal variation on Mercury. Unlike our planet, Mercury’s plane of spin is not tilted with respect to its orbit.
That being said, Mercury is the planet that is closest to the sun, at about 36 million miles. The distance from Mercury to earth reaches approximately 8.64 light minutes. This is roughly 97 million miles away. The planets diameter is 3,000 miles in length, which is quite small when taking in account that earth’s diameter is 8,000 miles.
Another factor is Mercury’s atmosphere, or rather, the lack of atmosphere. While many trillions of years ago, Mercury may have had a thriving atmosphere. Today begs a different story. Elements, such as sodium, potassium, and calcium, have been found lingering on the planet. Sadly, most of these elements are thrown from the surface by strong solar winds.
The orbit of Mercury around the sun moves faster when the two bodies are closer. This is referred to as Perihelion. When they are further away, the orbit is slower, which is known as Aphelion. Even though the speed of orbit fluctuates, Mercury’s axis rotation is not altered. The fluctuation in orbital speed does lead to an interesting sunset. If positioned within one of the two hot poles of Mercury, the observer would witness the sunrise when Mercury is at its furthest from the sun. The sun would then ascend slowly, increasing in size, until is passes overhead. It would stop and move backwards for eight earth days. This is due to the orbital angular velocity exceeding the spin velocity, or simply the planet is moving so fast one way that time appears to be reversing.
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After eight days, the sun moves forward shrinking in size as it nears the horizon. The sun finally sets 88 days after rising. Beside this weird observation of the sun, there are two important aspects of Mercury that are only found within this planet. These two features are the Caloris Basin and the Chao Meng-Fu Crater.
Mercury was depicted with a winged helmet and shoes and, often, a beautiful head of curly hair. He carried around a staff known as the caduceus, which is commonly depicted with two coiled snakes.
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CALORIS BASIN Starting with some basic Latin, the word Caloris translates to the word ‘heat’. This is a very suiting name, for the Caloris Basin is literally filled with lava. The temperature here can reach up to 430 degrees Celsius. This is the same as 806 degrees Fahrenheit. A key feature of this Basin is a crater that stretches 25 miles. Likely created due to a colossal explosion followed by volcanic activity, this crater rests near the center of the basin. It is surrounded by a hilly terrain and many valleys. It also has a pattern of troughs that radiate out. This is very similar in appearance to a spider web. In fact, the troughs led many astronomers to call the crater ‘Spider’. Unfortunately, the International Astronomical Union (IAU), also known as a group of total buzz killers, declared this name as being undignified.
They renamed it ‘Apollodorus’ after a 2nd century Greek architect. This architect was known for constructing Trajan’s Bridge and designing both the Forum Trajanum and Tajan’s Column. More importantly, he criticized the emperor of Rome and was banished. Later on, he was wrongfully accused of a crime and executed. Thus, deserving to be immortalized on the surface of Mercury. The troughs, following the theme set, were then named ‘Parthenon Fossae’. The word Parthenon is a shout out to the Greek temple of the same name, while fossae refers to a depression or crater.
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CHAO MENG-FU Chao Meng-Fu Crater received its name from the 13th century Chinese painter and calligrapher. He is famous for his paintings of horses, as well as his portrayal of landscapes.
However in comparison to these hotspots, The Chao Meng-Fu crater is even brighter. This is due to the crater having an usually reflective surface buried within it.
Unlike the common art style of the time, he did not separate foreground, middle ground, and back ground. Instead he would layer items at varying sizes to trick the eye.
Many speculate that ice may be the cause. Temperatures at the bottom of the crater never rise above -171 degrees Celsius, so it is possible for ice to remain on a planet so close to the sun.
The Chao Meng-Fu crater stretches 100 miles across the surface of Mercury with a ring of mountains surrounding its center. The most interesting fact about this crater is that the sun never rises high enough for the interior to receive sunlight. Using a radar telescope, astronomers have identified the area as being a radar hotspot. Bouncing signals off the planet, numerous bright patches can be observed, particularly at the north and south poles.
This reflection is not bright enough to be pure ice, but could possibly be a mixer of silicate rocks, which make up the surface of Mercury. The only remaining question is where did the ice come from.
THE SHROUDED PLANET
SHE IS BEAUTY, SHE IS GRACE, SHE IS CLOUDY IN SPACE
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Venus is famed as being the planet of the goddess of love and the Roman persona of Greek’s Aphrodite.
One year on Venus is equivalent to 225 days on earth, meaning that one day on Venus is longer than one year.
However, no one really knowns how the two became related. Venus was an Italian deity with no myths of her own. In some manner, she and Aphrodite became one in the same, allowing Venus to be recognized as other foreign goddesses.
Another interesting fact is that Venus, when compared to most planets, spins backwards. This could possibly be due to the planet’s tilt having started on its side followed by several collisions in the process of its formation.
Popular above all is the connection of Venus and Ishtar. Ishtar was the Babylonian goddess of love and prostitutes, but she also had what was known as ‘the star of Ishtar’. This star was in fact the planet we now call Venus. Venus is 25 million miles away from Earth. Its diameter is 7,520 miles, roughly 81.5% of the Earth’s mass in comparison. Venus spins rather slowly in comparison to the Earth. It takes 243 earth days for it to complete one rotation on its axis.
An unknown chaotic event and the drag of the planets heavy atmosphere may have also been the cause this. Unlike Mercury, Venus contains a very lively atmosphere. The surface appears as a bright, virtually featureless disc. This is due to the thick top layer of clouds and has coined the nickname “the shrouded planet.” This thick atmosphere baffled many of the first observers. They attempted to pinpoint specific features of the planet’s surface. Ultimately, they were just chasing shadows.
This thick atmosphere contains mostly carbon dioxide. Less than four percent is made up of nitrogen, with the lesser components of the atmosphere including sulfur dioxide and sulphuric acid. The thick yellow clouds are also notorious for acid rain. All of which makes Venus a particularly unpleasant place to live. But, these large amounts of sulfur should not be there. Sulfur compounds in Earth’s atmosphere are recovered by interactions with the surface rock. This leads to the idea that the surface of Venus must be very different, thus causing the absorption rate to be a much slower process in comparison. Another possible cause would be that there is a source of Sulfur dioxide on the planet. A likely candidate would be a large and active system of volcanoes.
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Venus does have lava plains and mountains that look very similar to Earth’s, and the lack of impact crater on the planet’s surface does suggest that lava has been flowing recently. Hotspots have been seen on Venus’ surface with infrared light. Idunn Mons, in the southern hemisphere, is one of the brightest hotspots. “Idunn” is the Norse goddess of apples and youth while “Mons” is Latin for mountain. It appears that a bright material flows away from the top of Idunn Mons’ crater, supporting the idea that it is a volcano. The fact that the material appears to be glowing is a sign that the material is relatively recent, or at least, it is new enough to not have been weathered by Venus’ atmosphere. Studies by Venus Express, a satellite sent by the European Space Agency, suggest that the most recent eruptions could have occurred between hundreds of millions of years ago or just a few hundred years back.
Depicted in many media, the Venus is a common idol respected by an array of ancient people. However, the Roman and Greek depicted is the most widely known.
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ASHEN LIGHT Another interesting feature of Venus is what is referred to as the “Ashen Light.” This is a mysterious glow claimed to be seen on the night side of Venus. It is said to be similar to the effect seen when the moon wanes into the crescent moon, but has yet to be scientifically explained. There are many hypothetical explanations of this phenomenon, such as it being caused by ultraviolet light from the sun. Nothing has been ridiculous as the inaccurate explanation proposed by German Astronomer Franz von Paula Gruithuisen. In the 1830s, Gruithuisen claimed that the lights that appear on the surface of Venus are the result of Venusian celebrations. Of course, Gruithuisen also thought the moon was inhabitable, so this hypothesis isn’t that outlandish for him.
While this is possibly be the least scientific explanation, he was right that the light lies on the hard surface of Venus. A logical explanation of these lights would be the natural glow of Venus. Due to the chemical make of Venus, the atmosphere, as well as the surface, glows slightly. There are still observers that speculate that this light may be an illusion. Spacecrafts that have looked for it have not been able to spot the light. This leads to the belief from some astronomers that it is just an enduring myth.
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MISSIONS TO VENUS While no one has attempted to land a man on the surface of Venus, there have been several attempts to land probes. In 1966, the Soviet probe Venera 3 crashed into the surface of Venus. The goal of this mission was to land a probe and return data. Sadly, the intense pressure of the Venusian atmosphere crushed it during its descent. In 1967, the Venera 4 enter the atmosphere and sent back data. This time the parachute worked and slowed the craft down during it descent to the surface. However, it was too affective and the descent took too long. Before the craft reached the surface, its batteries died. It wasn’t until 1970 that the Soviets were able to land a working probe on Venus. Venera 7, equipped with a smaller parachute, was the first successful probe.
This mission was followed by several more spacecrafts which landed successfully. They would send data back for less than a half hour before ultimately being destroyed by the extreme conditions on Venus. Missions from the United States and the Soviet Union continued exploration. In 1989, radar maps were created from the Magellan Probe. These maps revealed Venus’ surface in a three-dimensional form. In 2005, the European Space Agency (ESA) launched Venus Express. It entered the polar orbit in 2006 and sent back data on Venus’ atmosphere. It has since been retired.
THE ONE WE ALL CALL HOME EARTH AND ITS SISTER, THE MOON
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Our moon, like most moody teenagers, goes through phases within its life, but no matter its form it is still the moon and should be respected as such.
Among all the things that linger in outer space, the Earth is the only one we have first-hand knowledge of. After all, it is the planet we live on. Earth is dominated by blue oceans, an array of green and brown continents, and snowcapped poles. The surface is disguised with shifting clouds and the land is dotted with many artificial lights. The atmosphere contains a large amount of oxygen that is sustained by the plants which constantly replenish it. Our planet is thriving in comparison to the others that orbit around our sun. That does not mean we are alone. We share the space around our planet with over half a million items of man-made debris. There are about a thousand working satellites, but most is space junk. Dead satellites, pieces from space missions, and collisions of existing debris liter the more popular orbits.
The space age began in 1957 with the first artificial satellite, Sputnik 1. Before this, numerous failed attempts had been made. There is one ancient account documented of a Chinese space enthusiast named Wan-Hood. He tried to launch himself into outer space by attaching 47 gunpowder rockets to his body and ordering servants to light them at the same time. It was not successful. Of course, Earth is not alone within its orbit. Besides the mountains of space trash, our planet has a natural satellite we call a moon. The moon does more than just follow us our planet. It is one of the main causes of the ocean tides. Having its own force of gravity, the moon pulls our waters, creating currents. In hand, the Earth would do the same to the moon if it had water. Sadly, there are only rocks and dirt to be found.
As long as we remain on Earth, there is a part of the moon we will never see. This is the dark side of the moon. Also claimed by the phrase “far side of the moon,� we never see this side because of the moon’s orbit. The moon goes around the earth at the same speed it takes to spin on its axis, always keeping the same hemisphere facing us. There is a slight wobbling, but 41 percent of the moon is never visible from earth.
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THE NATURAL SATELLITE EARTH’S LITTLE SISTER
The moon is 1.28 light second from earth. This is equivalent to 250 thousand miles. A beam of light can travel this in over a second while it takes a man-made rocket three whole days. The moon is not a colorful world, and it lacks water, air, and life. But that does not mean it isn’t pretty. The moon’s surface is covered with an array of landscapes. While not as extensive as Earth’s, it contains mountain ranges, valleys, and numerous craters. After disembarking, the famous astronaut, Neil Armstrong, would later state that the moon “has a stark beauty all its own.” That being the great contrast between the grey surface and black skies. Mini markings of this excursion can still be seen today as the atmosphere does not change the surface of the moon. Left behind material, American flags, and a plaque bearing reminder to Apollo 11 still remain on the surface.
Of course, the flags have been bleached white from temperature exposure and most of them have been knocked down. The most obvious features of the moon’s surface are the vast dark areas traditionally called the seas. These spots were not created from water, but instead they were formed with lava, which spread across the surface billions of years ago. The lava lakes have since cooled and solidified, and besides the minor meteor impacts, have changed very little since. They also provided the perfect landing spot for all the Apollo mission except for one. Another marvel on the surface of the moon is the crater Copernicus. It was named by the astronomer Giovanni Batista Riccioli in 1651 while he drew the first useful lunar map. Riccioli believed that the Earth was the center of the solar system, a common belief then.
So, when Riccioli was naming the craters, he scornfully “flung Copernicus into the Ocean of Storms”. However, if his goal was to scorn his rival, he failed. This crater is one of the most impressive ones on the entire Lunar surface. It has been noted as having high terraced walls that reach up for miles above sunken floors. The rays of Copernicus spread out in many directions across the plains for 500 miles. This gives the clue that the crater must have been formed in the very last stages of the moon’s active period, as there are no signs of lava activity across the rays or on the crater’s floor. An example of a crater created earlier would be Stadiums, the ghost crater. Having been flooded with lava in the past, this crater is barely traceable. Ghost craters like this are not uncommon on the moon.
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THE LIGHTS ABOVE AURORA BOREALIS & AUSTRALIA
The Earth lies within a stream of energetic particles thrown into the solar system by the sun. As they approach the earth, most of the particles are deflected by our magnetic field. Those that are not deflected, are brought toward the earth’s poles. The particles then collide with the molecules making up the gases of the upper atmosphere. This action excites them and makes them glow. This process forms the Aurora Borealis in the Northern hemisphere and the Aurora Australia in the Southern hemisphere. It is the shape of the Earth’s magnetic field, which guides the particles into glowing rings. Solar winds are known to blow these particles around. When the sun is active and the solar winds are strong, these rings may reach up to the equator. This allows the Aurora Borealis to be seen in southern Europe, occasionally as far as Singapore.
Getting closer to the poles increases the chance of seeing an Aurora, but not too close as they rest at the center of the rings. The most popular color observed is a vibrant green. Occasionally ranges of red to pink and blue to purple can be seen. The different compounds that make up our planet’s atmosphere cause variations in color. Different atoms and different altitudes can give off different colors. Oxygen gives off a yellow-green light at an altitude of 60 miles. At 200 miles it gives of a red light. Ionic Nitrogen produces blue light and neutral Nitrogen gives off a redpurple that is rippled at the edges.
THE GOD OF WAR AND PEACE
HOW ORANGE BECAME THE NEW BLACK
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The planet Mars is the fourth planet from the sun and the last of the terrestrial planets. It has a diameter of four-thousand miles and is 33.9 million miles away from Earth.
The planet Mars was named after the Roman god of war and agriculture. He is often linked with the Greek god Ares for they share many characteristics, but they do differ slightly. The god Ares is known for being bloodthirsty and destructive. Mars represented military power, but he was not there for war alone. This power was a way to secure peace. Mars was paired with the Roman goddess Venus and depicted as a married couple in a large amount of art. The uniting of these two gods representing love and war was an important allegory for the people they stood to protect and care for.
Viewed from Earth, Mars has always been depicted as blood-orange in color. This isn’t entirely uniform. While a large part of the surface is orange in color, spots of black are flecked here and there and the polar regions are capped with white. The polar caps appear to be covered in ice. That’s because they are. Depending on the time of year, the caps will swell and shrink. This is due to seasons on Mars. When it is winter in the North, the Northern cap will grow and the Southern cap will shrink. The opposite will happen during winter in the Southern Hemisphere. The reason Mars has seasons is because the axis is tilted at 24 degrees with 24.5 hour days. This is very close to Earth.
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The surface of mars is filled with craters, mountains, huge volcanoes, and enormous valleys, but the Northern and Southern hemisphere contain very different terrain. The Northern hemisphere is covered with smooth plains. These were caused by lava that once flowed over the surface. It is easy to see that the surface in the Southern regions of Mars is much older. The surface is filled with an array of high mountains and deep and craters. It is still not fully understood why such a great difference remains on the surface. Evidence does elude to a massive impact. An object about half the size of our moon potentially crashed into the surface, but that doesn’t explain the differences. There are signs that before the large collision Mars was once a thriving planet. Marks from riverine channels snake across the surface.
Many features on the surface show signs of erosion by liquid. We know that there is water frozen in the polar caps of Mars, but to have supported liquid water on the surface, the atmosphere must have once been thicker. Currently, the atmosphere is composed of mostly carbon dioxide. The atmosphere is gradually escaping, and at its thickest is only one-tenth of the Earth’s atmosphere. It does seem that Mars’ climate is one that often repeats itself. Evidence can be seen in the polar ice, for it has formed in layers separated by other material. One possible cause would be a shift in the planet’s axis. The tilt mentioned earlier may have varied over the course of the millennia. A large shift could cause melting at the poles due to a full glare of the sun. There isn’t any evidence of such a dramatic shift on Earth for we have the moon to stabilize us.
While the climate of Mars is fascinating, it is also critical to those examining the planet for signs of life. It is tempting to think that a wetter Mars with a thicker atmosphere could sustain life, but the conditions for the emergence of life is still unknown. Finding nothing wouldn’t tell us much, but to find a fossil, let alone a living organism, would inform us of the possibility that life exceeds out planet. In fact, a group of researchers in the 1990s claimed to have found a meteorite with tiny structures resembling bacteria on it. Most scientists are skeptical of this statement and the debate continues on. The one thing everyone can agree on is that there is growing reason to explore the Martian surface thoroughly.
Much like our own planet, Mars is filled with an interesting terrain of mountain ranges; however, unlike earth, Mars has two moons.
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Mars contains to natural satellites referred to as moons. There named are Phobos and Deimos after the two Greek gods of panic and fear. These were also believed to be the sons of the God of war. Deimos is the smaller of the two and is very strange in shape. This is something similar to a distorted pear. It is only nine miles across at its widest and does not possess enough gravity to mold itself into a sphere. Deimos orbits 12,500 miles above the Mars’ surface. This is only a tenth of the distance of our moon from the Earth. Because it is so close, one revolution is completed every thirty hours. The surface bares very few large craters. Two of which are named Swift and Voltaire. These two honor eighteenth century authors who, oddly enough, suggested that Mars should have moons. This was long before any were actually observed.
The overall surface of the moon appears smooth. This is due to the surface being covered with a layer of fine dust called regolith. It coats Deimos and Phobos. The theory of Deimos is that it belonged to the asteroid belt. It may have strayed too close to Mars and was trapped by the planets gravity. If this were true, its orbit around Mars would be eccentric. Its actual orbit is also perfectly circular. Phobos orbits closer to Mars and is thought to have originated from the asteroid belt as well. Since it is closer, tidal forces would produce a circular orbit regardless of the starting conditions of the moon. Deimos’ orbit remains a mystery for the future to unravel.
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GLOSSARY OF SCIENTIFIC TERMS BIG WORDS WITH EVEN BIGGER MEANING
APHELION: The point of an object’s orbit when it is farthest from the sun. ASTEROID: Small rock body revolving around the sun. The majority of asteroids orbit between Mars and Jupiter, in the asteroid belt. ATMOSPHERE: The gas layer surrounding a planet or store That is retained due to the gravitational field and temperature around the object. CONSTELLATION: A shape assigned to an arrangement of stars that serve as a tool to differentiate between the stars. There are 88 different shapes identified. CORE: The dense, enter most part of a planet, large moon, asteroid, or star. CORONA: The sun’s outer most atmosphere. The visible light from the sun that can be seen around the moon during an eclipse.
CRUST: The solid outermost layer of an object. DENSITY: The ratio of the mass of an object to its volume. DWARF PLANET: A body orbiting the sun that has sufficient mass to be nearly round in shape, but has not cleared its path of other bodies of comparable size. ECLIPTIC: The path of the planets orbit. GALAXY: A large collection of stars bound by mutual gravitational attraction. GAS GIANT: A large, low-density planet that is composed primarily of gases. INFRARED: Having a wavelength longer than the red end the visible light spectrum and shorter than that of microwaves. INNER PLANETS: The planets closest to the sun. Also called Terrestrial planets.
LIGHT-YEAR: The distance light travels in a vacuum in one year. MILKY WAY: The large spiral galaxy that is home to our solar system. PERIHELION: The point of an object’s orbit when it is closest to the sun. PLANET: About in orbit around the sun, possessing significant mass to form in nearly round shape, and gravitationally dominant. ORBITAL SPEED: The speed of a planet, natural satellite, artificial satellite, or a another star orbits a much larger object. SATELLITE: A natural or artificial body that orbits the earth, a moon, or a planet.
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BIBLIOGRAPHY
THE REAL BRAINS
“Constellation Guide.” Constellation Guide. Web. 16 November 2017. Davis, Kenneth. Don’t Know Much About Mythology. Harper Paperbacks, 2006. Print. 11 September 2017. May, Brian, et al. The Cosmic Tourist: Visit the 100 Most Awe-Inspiring Destinations in the Universe. Carlton Books, 2016. Print. 31 October 2017. Murdin, Paul. Secrets of the Universe: How We Discovered the Cosmos. The University of Chicago Press, 2010. Print. 31 October 2017. Sampaolo, Marco, et al. “Venus: Roman Goddess.” Encyclopedia Britannica. 23 July 2016. Web. 16 November 2017. Trefil, James. Space Atlas: Mapping the Universe... National Geographic 2014. Print. 31 October 2017.