Hitchhiker's Guide to the Solar System

THE HITCHHIKERS GUIDE TO THE SOLAR SYSTEM Alexis Stormer ASTRO 103 Professor Michelle Cullen 1

TABLE OF CONTENTS Introduction………………………………………………………3 Jupiter, Saturn, Uranus, and Neptune……….......31 Constellations of the Seasons……………………………4 Jupiter…………………………………………32 Saturn………………………………………….34 Introduction……………………………..5 Uranus…………………………………………36 Winter………………….…………………..6 Neptune………………………………………38 Spring……………………………………....8 Summer………………………………….10 Dwarf Planets, Asteroids, and Comets……………40 Fall………………………………………….12 Dwarf Planet………………………………..41 The Sun……………………………………………………………14 Comet………………………………….………42 The Moon and the Earth………………………………….18 Asteroid……………………………………….44 The Moon……………………………….19 The Earth………………………………...22 Works Cited……………………………………………………45 Mercury, Venus, and Mars……………………………….24 Mercury…………………………………..25 Venus………………………………………27 Mars………………………………………..29 2

INTRODUCTION Welcome to the Hitchhiker’s Guide to the Solar System! This book provides insight to many great parts of our Solar System including planets, constellations, and other celestial beings. This book was made for Professor Cullen’s Solar System Astronomy class as the University of Alaska Anchorage This book is in honor of the great Carl Sagan, Douglas Adams, and our wonderful professor, Michelle Cullen. 3

CONSTELLATIONS OF THE SEASONS 4

INTRODUCTION In this section, we will be going over a We will discuss the constellation for each season and the following asterisms, prominent stars, galaxies, constellations: and other celestial objects that may ▪ Winter: Reticulum belong with them. ▪ Spring: Corvus ▪ Summer: Scutum But what exactly is a constellation? It is ▪ Fall: Andromeda a group of stars that form a recognizable pattern. Constellations are traditionally named after its mythological figure or its appearance. An asterism is a prominent pattern of stars, but is not big enough to be considered a constellation. 5

WINTER: RETICULUM 6

WINTER: RETICULUM Official name: Reticulum Translation: “the reticle” or “small net” Story of Reticulum’s Discovery: Reticulum was discovered in 1621 by Isaac Habrecht II, naming it Rhombus. In the 18th century, Nicolas Louis de Lacaille renamed the constellation to Reticule Rhomboide to commemorate his telescope reticle, which he used to measure star positions during a trip to Cape of Good Hope in the early 1750s. The constellation was later Latinized to Reticulum. How to Locate: Reticulum is located in the first quadrant of the southern hemisphere, where it can be located at the latitudes of +23 deg and -90 deg during the months of October and December for the best views. Special Celestial Objects: Reticulum is home to NGC 1313, or the Topsy Turvy Galaxy. This is a barred spiral galaxy with a diameter measuring in at about half the size of our Milky Way Galaxy (50,000 light-years)! 7

SPRING: CORVUS 8

SPRING: CORVUS Official Name: Corvus, also known as Raven Translation: Latin for “crow” Myth Behind Corvus: The name of Corvus represents the Greek god Apollo’s raven adorned with white feathers. In one of the stories involving Corvus, Apollo told the raven to watch Coronis, his pregnant lover. Over time, Coronis lost interest in Apollo and fell in love with another individual. When Corvus reported this to Apollo, Apollo was furious that Corvus did not stop Coronis’s affair. Apollo acted out in anger and cursed Corvus, scorching its feathers to a black color. Therefore, ravens are black, according to the myth. How to Locate: Corvus is located in the southern hemisphere’s third quadrant, which can be found between the latitudes +60deg and -90. For the best view, it can be seen during the night on the southern hemisphere during the month of May. Special Celestial Objects: Corvus is home to a few notable objects. Within Corvus lies the asterism called The Sail, made out by Corvus’s four brightest stars. Corvus is also home to the Antennae Galaxies, two interacting galaxies going through a starburst phase. 9

SUMMER: SCUTUM 10

SUMMER: SCUTUM Official Name: Scutum, originally known as Scutum Sobiescianum Translation: Latin for “the shield” Story of Scutum: Scutum first introduced the astronomer Johannes Hevelius around the 17th century. It was originally named Scutum Sobiescianum in honor of King John III Sobieski by Hevelius to commemorate a battle victory Sobieski led. The name was later shortened to Scutum. How to Locate: Scutum is located in the southern hemisphere’s fourth quadrant, which can be found in the latitudes of +80deg and -90deg. Scutum is best seen during August nights on the southern hemisphere. Special Celestial Objects: Within Scutum, the Wild Duck Cluster, or Messier 11, lies. This is one of the richest, most compact open clusters known to us currently. 11

FALL: ANDROMEDA 12

FALL: ANDROMEDA Official Name: Andromeda, commonly known as the Chained Maiden, Persea, and Cepheis Translation: translates to “the Chained Woman” Myth Behind Andromeda: Andromeda was the daughter of Queen Cassiopeia and King Cepheus. Cassiopeia was known to be very vain and said she was the most beautiful woman, more beautiful than the sea nymphs near her. This angered the nymphs and their sea god Poseidon. As revenge, Poseidon ravaged their kingdom by sending a sea monster known as Cetus. In order to stop the madness and destruction, Cepheus consulted the Oracle of Ammon, who suggested the only way to stop this was to offer his daughter to the sea monster. The king proceeded to chain his daughter to a rock to be scarified. However, she was rescued by Perseus, and they fell in love. When Andromeda died, the Greek goddess Athena honored her by placing her in the sky close to her loved ones. How to Locate: Located between the latitudes +90deg and -40deg. It can be seen in the northern hemisphere between June and February. Special Celestial Objects: Located within Andromeda is the Andromeda Galaxy, which can be seen with the naked eye here on earth. The Andromeda Galaxy is the most distant object that we can see without using anything but our eyes! 13

THE SUN 14

THE SUN The Sun render, https://toppng.com/sun-transparent-background-PNG-free-PNG-Images_87016 15

THE SUN • Names: Sun, Sol, Helios • The Sun contains a magnetosphere, which is a magnetic field that gets carried • Origin: Seen as a God in many cultures, through our Solar System in all directions named after the mythological gods Sol by Solar Wind. and Helios • The magnetosphere carries the Sun’s • The Sun is ball of helium and hydrogen Solar Flares, which interact with our composed of many layers. The core emits planet. energy that radiates to the radiation zone, that takes 170,000 years to rise to the Convection zone, where it begins to become bubbly hot plasma. • After the Convection Zone, the atmosphere begins with the Photosphere, that we commonly refer to as the “surface” that holds Sunspots. Next, we have the chromosphere, which gives the red glow we see, and the Corona, where nuclear fusion occurs. Outline of the Sun’s layers, https://www.nasa.gov/mission_pages/sunearth/science/Sunlayers.h1tm6l

PARKER SOLAR PROBE SUN MISSION ▪ One of the most exciting missions to date is the Parker Solar Probe mission, which is focused on research on the Sun. ▪ The Solar Probe launched board ULA’s Delta Heavy rocket in August 2018. ▪ This mission is an active mission, which will last approximately 7 years and end in late 2025. The data gathered by the probe will allow us to research the Sun’s solar activity in closer detail. ▪ With this information, we will be able to provide more accurate forecasts on major solar weather events that may impact our planet. ▪ The Parker Solar Probe is the closest spacecraft to ever reach the Sun. ▪ Like most missions, NASA predicts this will come with more questions than answers. The Delta Heavy that carried the Parker Solar Probe, http://parkersolarprobe.jhuapl.edu/The-Mission/index.php 17

THE MOON AND THE EARTH 18

THE MOON Diameter: 3,475km Distance from Earth: 0.002569 AU Moon transparent image, https://www.freeiconspng.com/downloadimg/44668 19

THE MOON • One of the many stories about the Moon • The Moon has some unique aspects to it is the Polynesian tale of the “Moon such as its maria, highlands, and craters! Woman”. Legend has that a Polynesian woman who wanted to live in the • The Maria, Latin for “seas”, are composed heavens, so she walked along the rainbow of dark lunar plains that are originally until she reached the Moon. She can be believed to be filled with water but are spotted on the Moons beating her tapa currently filled with solidified pools of board to make cloth. basaltic lava. • The Moon has a very distinct crust, as well • The Highlands are the lighter colored as a mantle and core. The inner core is parts of the Moon that represent ancient made of a solid iron, and the outer core is crust that was created by meteoritic made of a fluid composed primarily of bombardment. iron. • The Craters of the Moon are impact craters that greatly impact the surface caused by asteroids and comets. There are more than 300,000 craters wider than 1km on the surface of the Moon. Some of the more prominent craters are named! Moon craters, 20 https://www.syfy.com/sites/syfy/files/styles/blog_post_featured _media_tablet_1_5x/public/lro_boguslawskye.jpg?h=ec7a171c

LUNAR MISSION APOLLO 17 • The final expedition to the Moon was the Apollo 17 mission. • This mission began in December of 1972 aboard a Saturn V rocket. The last manned lunar mission was almost FIFTY YEARS AGO. • During this mission, the astronauts obtained what is known as one of the best lunar rock samples, Troctolite 76535. • This sample is thought to be 4.5 million years old and provides evidence that the Moon once had a magnetic field like Earth! An astronaut on a buggy during the Apollo 17 Mission, https://upload.wikimedia.org/wikipedia/commons/thumb/4/4d/NASA_Apollo_17_ Lunar_Roving_Vehicle.jpg/390px-NASA_Apollo_17_Lunar_Roving_Vehicle.jpg 21

EARTH Diameter: 12,760km Mass: 5.98 x 10kg Distance from the Sun: 1 AU Earth, 22 https://upload.wikimedia.org/wikipedia/commo ns/thumb/2/22/Earth_Western_Hemisphere_tr ansparent_background.png/900px- Earth_Western_Hemisphere_transparent_backg round.png

EARTH • Also called Gaia, Terra, Tellus, the “world”, • Earth’s atmosphere is made primarily of and Pale Blue Dot. Nitrogen, Oxygen, Argon, and other trace gasses (like Carbon Dioxide). The • A myth about the Earth is that the planet atmosphere has many layers: the itself is completely flat, and not rounded. exosphere, thermosphere, mesosphere, Many believed this until Aristotle provided stratosphere, and troposphere. strong evidence that the Earth was spherical in 330 B.C. • In December of 2001, NASA Launched the JASON Mission. This mission is • The Earth has three additional layers currently active and has continued to underneath the crust. provide information. • The mantle, which makes about 84% of the • This mission mapped sea levels, wind Earth’s volume, is predominately solid speeds, and wave height to provide more composed of mostly silicates. insight to more accurate weather, sea levels changes, and better climate • The outer core is liquid, made up of 80% forecasts. iron, along with nickel and other trade lighter elements. • The inner core is solid and made of iron and nickel like the outer core. 23

MERCURY, VENUS, AND MARS 24

MERCURY Distance from the Sun: 0.4 AU Mass: 3.3011 x 1033 kg Orbital Period: 87.969 days Mercury, https://www.stickpng.com/img/do wnload/580b585b2edbce24c47b27 09 25

MERCURY • Mercury’s core occupies about 55% of it’s ▪ NASA’s MESSENGER mission: volume and it has been suggested that it is ▪ The mission launched in 2004 molten. and finally made orbit around • The mantle of the planet is made of Mercury in 2011. silicates, and the surface is made of impact ▪ This mission found high craters, much like the Moon, and narrow concentrations of magnesium ridges that are thought to the core rising to and calcium on the dark side the surface and cooling. of the planet, known as the “night side”. There was also • Mercury’s atmosphere is not a complete water found in the exosphere, atmosphere, but instead is a thin indicating evidence that there exosphere made up of atoms that have was past volcanic activity on blasted off of the surface from meteoroid the surface. impact and solar winds. 26

VENUS Distance from the Sun: 0.7 AU Mass: 4.867 x 1024kg Orbital Period: 224.701 days 27

VENUS • Venus is known as one of the four Venus Highlands, terrestrial planets or known as “rocky https://www.esa.int/var/esa/storage/images/esa_multimedia/images planets”. /2005/08/radar_image_of_surface_of_venus/10175413-2-eng- GB/Radar_image_of_surface_of_Venus_pillars.jpg • Venus is often compared to Earth as the “sister planet” due to the similarities of their surfaces. However, Venus is way hotter averaging at 867℉ on the surface. • The geology of Venus is very similar to Earth. Most of the surface consists of volcanic bedrock. • Like the Moon, Venus has highlands that take up about 10% of the surface. • The atmosphere is very dense, made up of approximately 96.5% Carbon Dioxide and 3.5% Nitrogen. The mass of the atmosphere is 92 times that of Earth. 28

MARS Distance from the Sun: 1.5 AU Mass: 6.4171 x 1023kg Orbital Period: 686.980 days 29

MARS • The surface of Mars is composed of iron • The most notable NASA Mars Mission is oxide that gives the planet its notable red the Perseverance Rover surface. • This Launched in July of 2020 and landed • Mars is one of the four terrestrial planets on the surface of Mars February 2021. made of silicone, oxygen, metals, and other materials within the rocky surface. • The goal of this mission is to find signs of habitable conditions, as well as signs of • The interior is a dense metallic core past microbial life. consisting of iron and nickel with sulfur. The core is surrounded by a mantle made • This mission will also test the ability to of silicate that formed the planet’s produce oxygen on Mars and is tectonics and volcanic features. programmed to detect signs of water. • The atmosphere is primarily carbon • The mission is expected to end in 2022. dioxide, and very dusty, which can be seen from the surface. Like Earth, Mars can produce an aurora towards the Northern and Southern hemispheres. Perseverance on Mars, 30 https://www.google.com/url?sa=i&url=https%3A%2F%2Fmars.nasa.gov%2Fmars2020%2F&psig=AOvVaw3jIJkkc HCU03YjICuOasNj&ust=1638687298152000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCMjZ9ITIyfQCFQAAA AAdAAAAABAO

JUPITER, SATURN, URANUS, AND NEPTUNE 31

JUPITER Distance from the Sun: 5.2 AU Mass: 1.89 x 1027kg, or 317.8 Earths Orbital Period: 11.86 years Number of Moons: 80 Jupiter, 32 https://www.pngitem.com/download/JTiohx_jupiter- planet-freetoedit-jupiter-transparent-hd-png- download/

JUPITER • Named after the Roman Mythology god • Jupiter’s rings are composed of small Jupiter, or “Jove”, who was the god of the particles that are difficult to see unless sky and thunder and was known as the they are backlit by the Sun. These rings king of the gods. are suggested to be made of dust from meteoroids smashing into Jupiter’s many • This gaseous planet’s interior is made Moons. primarily of liquid hydrogen and helium with a small core that is thought to be • Jupiter has 80 Moons, the most rocky. The pressure from the gasses is 100 interesting being Callisto. It is the 3rd million times that of our atmosphere’s. largest Moon in the Solar System, discovered by Galileo Galilei. It is the • The atmosphere is the deepest known in oldest and most heavily cratered Moon, the Solar System, made of the previously which gives it a very beautiful mentioned hydrogen and helium, with a appearance. trace amount of ammonia and methane. • There is no real “surface” of Jupiter, as the atmosphere extends to the small core of the planet. Callisto, https://en.wikipedia.org/wiki/File:Callisto.jpg 33

SATURN Distance from the Sun: 9.5 AU Mass: 5.6834 x 1026kg, or 95.15 Earths Orbital Period: 29.46 years # of Moons: 82 Saturn, 34 https://www.seekpng.com/idown/u2e6e6t4q8r5u2e6_s aturn-saturn-planet-transparent-background/

SATURN • Named after the Roman God Saturn, the • The rings of Saturn contain billions of god of plenty, wealth, and agriculture. pieces of ice and rock covered in dust. These are thought to contain pieces of • Saturn’s interior is very hot, consisting of comets, asteroids, and shattered pieces mostly hydrogen and helium like its of Moon torn apart by Saturn’s strong neighboring planet, Jupiter. The core is gravity. These rings extend out about very similar to Earth’s but is denser. 282,000km and are all named. Some of these rings are home to Saturn’s many • The atmosphere is composed of clouds Moons. that give Saturn a very striped appearance, with an outer atmosphere made primarily • One of Saturn’s Moons is Fenrir, named of molecular hydrogen. after Norse mythology god Loki’s wolf son. Fenrir is interesting as it orbits in • In 1977, NASA’s Voyager 1 launched and retrograde and is more elongated than it reached Saturn in 1980, where it is circular. discovered three of it’s Moons, Prometheus, Pandora, and Atlas. This provided us with more data about Saturn’s Moons, especially Titan, which we learned more about its extremely thick atmosphere. Saturn’s rings, 35 https://spaceplace.nasa.gov/saturn-rings/en/

URANUS Distance from the Sun: 19.8 AU Mass: 14.53 Earths Orbital Period: 84.02 years # of Moons: 27 Uranus, 36 https://www.pngitem.com/middle/mbRiJo_uranus-planet-png-transparent-png/

URANUS • Named after the Greek God of the Sky, • Uranus has two sets of rings. The inner Uranus. set has 9 rings that are a dark, narrow gray color. The outer set consists of two • Consists of three interior layers, the rocky rings, the inner ring being a reddish rust core, icy mantle, and outer gaseous color, and the outer being blue. These envelope. Like its sister gaseous planets, it rings are horizonal, unlike the sister is made primarily of hydrogen and helium. planet’s vertical rings. • Uranus’s temperature is much lower than • Uranus has a Moon named Puck, which the other gaseous planets, but scientists was discovered by NASA’s Voyager 2. It Is are unable to explain why. The minimum the largest of the lesser-known Moons temperature is 49°K and is named after William Shakespeare's “a Midnight Summer Dream”. • The atmosphere is made mostly of hydrogen and helium, with small amounts of methane, water, and ammonia. The methane gives Uranus its unique blue color. Uranus’s rings, https://www.space.com/45-uranus-seventh-planet- in-earths-solar-system-was-first-discovered- planet.html 37

NEPTUNE Distance from the Sun: 30 AU Mass: About 57.74 Earths Orbital Period: 164.8 years # of Moons: 14 Neptune, 38 https://www.seekpng.com/idown/u2a9o0i1q8y3u2r5_neptune-neptune-transparent-background/

NEPTUNE • Neptune is named after the Roman god of • Neptune’s rings are thought to be young the sea. and short-lived in age. The rings of Neptune are unique, as they have clumps • The planet is made of a thick fog of dust called “Arcs”. These arcs make the composed of water, ammonia, and rings unique as the Laws of Motion methane. Neptune has a rocky core that is suggest that they would break apart, but thought to be like Earth’s. do not. It is believed that this is because the Moons of Neptune’s gravities hold • The atmosphere is made of hydrogen and them together. helium, with methane and an unknown component that causes its unique blue • Neptune has a Moon named Hippocamp, color. or S/2004 N1. This is Neptune’s smallest Moon and is believed to be a broken off • It is known as containing the windiest piece of another Moon, Proteus. atmosphere in the Solar System, with winds 9 times stronger than Earth’s! Neptune’s rings, https://solarsystem.nasa .gov/resources/249/nept unes-rings/ 39

NOTABLE DWARF PLANET, ASTEROID, AND COMETS 40

DWARF PLANET MAKEMAKE Name Origin: Named after the Easter Island Artistic Recreation of Makemake, creator of humanity and god of fertility. https://nineplanets.org/wp-content/uploads/2019/09/makemake.png Distance from the Sun: 45.8 AU Orbital Period: 306.21 years Properties of Makemake: There is very little known about the makeup of Makemake as of today. It is thought to contain ethane, methane, and high-mass alkanes such as propane. The surface is covered with methane ice and nitrogen. Atmosphere: At the current time, it does not seem as if Makemake has an atmosphere, but it is suggested that it would be similar to Pluto’s. Artistic recreation of Makemake’s surface, 41 https://cdn.eso.org/images/newsfeature/eso1246a.jpg

HALLEY’S COMET Image of Halley’s Comet, https://upload.wikimedia.org/wikipedia/commons/thumb/2/2a/Lspn_comet_halley.jpg/1200px- 42 Lspn_comet_halley.jpg

HALLEY’S COMET • Name Origin: Named after Edmond Halley, Notable Info About the Comet: who researched three previous comet • Considered a “periodic” comet that sightings and concluded that they were all the same comet and predicted the next returns its orbit near Earth every 75 sighting. Unfortunately, Halley never got to years. Its last appearance was in 1986, see the comet himself. and its next appearance will be in 2061. • Orbital Period: 75.32 years • Sightings of the comet appear all over history throughout the world! • Internal Composition: The internal components of Halley’s Comet, known as Mission Giotto the nucleus, contains oxygen, carbon, and nitrogen primarily. This comet is known as • Launched in July of 1985 the home to the most unprocessed • This was the first deep space mission by material in the Solar System! Halley’s Comet is 15km long, 8km wide, the ESA and became the first mission to and thought to be 8km thick. The coma or ever get close-up images of a comet’s surrounding “tail” is thought to be nucleus. 100,000km across. • This mission allowed us to find the shape and size of Halley’s Comet. Image of Halley’s Comet from the Giotto Mission, 43 https://www.esa.int/var/esa/storage/images/esa_ multimedia/images/2012/11/comet_halley_close_u p/12125416-3-eng- GB/Comet_Halley_close_up_pillars.jpg

ASTEROID 1862 APOLLO • Name Origin: Named after Greek Notable Information: God Apollo. Apollo is the god of • Due to the asteroid’s path around the prophecy, oracles, and much more. sun, it is considered a hazardous • Orbital Period: 1.78 years asteroid to us, but is not an immediate • Distance from the Sun: 2.29 AU concern. • Size comparable to the US Pentagon and is one of the biggest asteroid in the asteroid belt! Rendering of 1862 Apollo, https://www.spacereference.org/static/data/shapefiles/damit/A208.M273.shape.png 44

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