Planets, Dwarf Planets and moons of our Solar System Terrestrial Planets Planets, Dwarf Planets and moons of our Solar System Jovian Planets

Mercury Area not mapped by Mariner 10 Second smallest planet Diameter 3,029 miles (4,875Km) Rich in iron Barely any atmosphere because low gravity and sun’s heat burns away Heavily cratered due to lack of atmosphere Gases of thin atmosphere= 52% Oxygen, 39% sodium, 8% Helium 800°F during the day, -290°F at night 28.6 million miles(46 mill km) from sun Aphelion= 43 million miles Perihelion= 29 million miles Surface observations were made by the Mariner10, which passed close to Mercury in 1974-1975. More WILL be learned from the Messenger Mission in 2011 (Japan and Europe). Area not mapped by Mariner 10 Matisse Crater

Mercury-named after the god of speed for its quick revolution Very thick iron core Very dense planet Iron creates magnetic field but only 1% the strength of Earth’s magnetic field. Explored by Mariner 10 in 1974 and 1975, along with Venus Rotation Period = 59 Earth Days Revolution= 88 Earth days 0 Moons – WHY??? Gravity =.38 that of Earth Image of frozen south pole taken from the Mariner 10 spacecraft

Venus- named after the Goddess of beauty for the way that it shines in the night sky Also know as Earth’s twin because identical in size and composition. 67.2 mill miles (108.2 km) from sun Diameter 7,521 miles (12, 401 km) 0 Moons Rotation= 243 Earth days (Only Planet that its day is longer than its year!) The orbit is almost a perfect circle rather than elliptical like all others Revolution= 224.7 Earth days Gravity= .9 that of Earth Venus also does not have seasons because its axis only tilts 2.6° Venus is the brightest planet in the night sky due to its thick atmosphere. Can be seen in early morning or evening in the night sky.

Venus’s Atmosphere Atmosphere is extremely dangerous 96.5% Carbon Dioxide 3.5% nitrogen and trace gases The high amount of carbon dioxide causes extreme global warming from the Greenhouse Effect. Surface temperatures 867°F The clouds(3 distinct layers of thick clouds) are a very thick sulfuric acid. The pressure inside Venus’ atmosphere is equal to being at 3,000 ft deep in one of our oceans! In 1978, Pioneer-Venus and 1989 Magellan missions of the United States used radar to map 98% if the surface of Venus! 2006 a European Probe was sent to monitor Venus’s atmosphere for 1 and ½ years.

Venus’s Surface Maat Mons, the largest volcano on Venus (3 miles high) The interior of Venus is believed to be very similar to Earth, except for a rocky mantle. It has a molten iron and nickel outer core and solid iron and nickel inner core Also formed 4.5 billion years ago with the same materials as Earth. Venus is similar but does NOT have Plate Tectonics. Although, Venus’s surface is covered in mountains, plains and very active volcanoes. Over 20 probes have been sent to Venus to explore its atmosphere and surface! Venus’s surface is covered in old lava flows from about 500mya.

Earth 93 million miles (149.6 mill Km) from the Sun Gravity = 1.0 Rotation= 23.93 hours Revolution= 365.26 days (this is why we have Leap Years) Diameter =7, 926 miles (12, 756 Km) Have four distinct seasons due to 23.5° tilt Molten mantle which allows for Plate Tectonics Plate Tectonics not only create and change our surface but it volcanic eruptions created water on Earth! Only planet with H2O Water! Only planet with specialized atmosphere that protects the surface from impacts and radiation from sun. Extremely strong Magnetosphere Atmosphere= 78% Nitrogen, 21% Oxygen Only Planet with LIFE!

Mars- Named after the god of war for its red color 141.6 mill miles (227.9 mill Km) from the Sun Surface Temperatures -195°F to 77°F Diameter= 4,213 miles (6,780 Km)- About half the size of Earth. 2 Moons (Deimos and Phobos) Both moons of Mars are captured asteroids. Gravity= .38 that of Earth Rotation= 24.63 hours Revolution= 687 Earth days Atmosphere= 95.3% Carbon Dioxide, 2.7% Nitrogen, 1.6% Argon Atmosphere is extremely thin with a very cold and dry surface. Mars has very distinct North and South poles which are mainly carbon dioxide ice. Retrograde Motion- apparent backward motion of a planet The poles shift during seasons. The season are caused but tilt in axis as well as eccentric orbit! Mars’s thin atmosphere retrograde 2 RETROGRADE MOTION

Surface of Mars Iron Oxide in the soil causes the reddish-brown appearance. Mars’s surface is covered in steep valleys, craters and large volcanoes. Mars’s contains the solar systems’ largest volcano- Olympus Mons (larger than Colorado!) Mars does show evidence of ancient water flows in water created valleys. But now the surface is too cold for water in a liquid state. The surface is covered in rocks and sand dunes. The poles are full of highlands and mountains as well a carbon dioxide ice. The planet also experiences dust storms that cover the planet. The dust clouds can be 3000 ft high and last for weeks! The 2001 Mars Odyssey and Global Surveyors in 2003 explored Mars for our most recent data.

Valles Marineris lies on the equator of Mars and is almost 10 times longer and 3 times deeper than the Grand Canyon! This canyon was created over 3bya by shifting of Mars’s crust.

Jupiter Largest planet- 2.5 times the mass of all other 8 planets combined. Distance from Sun-=483.6 million miles Diameter= 88,846 miles (10 times the diameter of Earth and 318 times more massive than Earth) Number of Moons= 63 Rotation= 99.3 hours (Quicker spin on axis than any other planet) Revolution= 11.86 Earth years Gravity= 2.64 times that of Earth Difference of 47.3 million miles between Aphelion and Perihelion Atmosphere=89.8% Hydrogen, 10.2% Helium Temperature= -166°F Rings= 2 faint rings- observed by the Galileo spacecraft during its five year mission around the planet Solid core- of rock, metal and hydrogen compounds. Magnetic Field- larger and stronger than any other planet(20,000 times stronger than Earth’s), and actually causes Aurora on the poles of Jupiter! The Great Red Spot- is a storm (hurricane) larger than Earth that has been rotating around the planet and as been observed for the past 340 years.

Jupiter’s Interior The composition of Jupiter's interior is mostly the simple molecules hydrogen, in the form of liquid. Under the cloud layers, when the pressure of the interior becomes high enough, the hydrogen of which Jupiter is made changes to liquid hydrogen, which gradually changes further to liquid metallic hydrogen. The core of Jupiter is made out of heavier, rocky and metal elements. Electric currents exist in the metallic layer, these create Jupiter’s magnetic field.

Jupiter Jupiter and its most interesting moon, Io. The strength of Jupiter’s gravity is enormous. In 1993 Jupiter ‘s gravity pulled apart the Levy9 comet and the pieces crashed into Jupiter, as seen above. Jupiter’s Moons (Galilean Satellites -after their discoverer): Io- most volcanic object in solar system, orbit is only 42.5 hours around Jupiter Ganymede- largest moon in solar system, made of rock and carbon dioxide ice Callisto- much brighter than our moon (ice reflects more sunlight) darker regions are rock Europa- ice-covered ball of rock, average temp around -225°F, may have liquid seas under the ice which could have simplistic life forms!

Saturn Distance from Sun= 888 mill miles Temperature= -220 °F Hubble image of Saturn with an image of shadows created by some of Saturn’s orbiting moons. Distance from Sun= 888 mill miles Temperature= -220 °F Diameter= 74, 898 miles Number of moons= 62 Rotation= 10.66 hours Revolution= 29.46 Earth years Gravity= 1.07 that of Earth Atmosphere= 96.3% Hydrogen, 3.7% Helium and trace gases with ammonia ice near the cloud tops. Saturn can be observed from Earth with a naked eye 10 months out of the year. It appears pale yellow due to the thick cloud layers (3 distinct layers). Saturn also experiences Auroras from the Sun’s solar wind that can been seen on its southern pole. Saturn's’ magnetic field is a 1000 X’s larger than the Earth’s! Five space probes have been on missions to orbit this planet since 2004

Titan- Saturn’s largest moon Saturn’s Rings Titan- Saturn’s largest moon (larger than Mercury!) Discovered in 1655 Only moon with substantial atmosphere, similar to a young Earth Very nitrogen and methane rich atmosphere Size of Mercury Made of rock, ice and water -292°F Saturn’s Rings (Image taken by Voyager Probe) Saturn’s rings are made up of collections of separate pieces of dirty waters and rock particles. These pieces can range from microscopic pieces to larger than some houses. There are 7 major rings and each ring is made up of smaller rings called ringlets. These particles reflect a lot of light presenting a beautiful color display. These rings change as the moons move through them. Saturn’s rings are paper thin, in comparison to the size of the planet. Origin of the rings is most likely an object that was shattered by an asteroid or a moon broken apart by Saturn’s gravity. In 2005, the orbiter Cassini sent a probe to examine the atmosphere of Triton Saturn’s rings, taken by the Voyager probe

Uranus Distance from the Sun= 1.78 bill miles Cloud Temperature= -353°F Diameter= 31,763 miles Numbers of moons= 27 Rotation=17.24 hours Revolution=84 Earth years Gravity= .89 that of Earth (at cloud tops) Twice as far from the sun than Earth 4 times the size of the Earth Retrograde revolution= Uranus has retrograde revolution which means that it revolves the opposite direction of the other planets *Due to a planet-size impact, Uranus’s axis has been know onto its side at a 98° tilt! *Uranus also has 11 rings

Uranus Atmosphere= 82.5% Hydrogen, 15.2% Helium, and 2.3% Methane (small amount of methane creates the pale blue color) The surface is made up of methane water and ammonia ice. Electrical currents in the ice create a magnetic field on Uranus. The interior is a rocky/icy core. Seasons last for 21 years, due to extreme tilt. In 1986, Voyager 2 flew by Uranus and provided detailed information about the planet. Uranus has many smaller moons with five major moons. Most of the moons follow the retrograde revolution like Uranus. Most moons are made up of rock and ice.

Neptune-The Blue Planet Average distance from the sun= 2.8 billion miles Cloud Temperature= -320°F Diameter= 30,760 miles (about time s Earth) Number of Moons= 13 Rotation= 16.11 hours Revolution= 164.9 years Gravity= 1.13 that of Earth Atmosphere= 79% Hydrogen, 18% Helium 3% Methane Does have seasons due to 28.3% tilt Similar to Uranus, Neptune has a surface of water and methane ice with a similar icy or rocky core. Neptune has six thin rings, microscopic material and difficult to see. Neptune was first discovered mathematically using the Universal law of Gravitation in 1846. Voyager 2 flew by Neptune in 1989 to provide the first detailed images of the blue planet. The Great Dark Spot- is a hurricane like storm almost as big as Earth BUT the storm disappeared in 1994.

Neptune and its moons Triton- Neptune’s only major moon Triton was discovered 17 days after the planet’s own discovery Similar to our moon, Triton’s synchronous, only one side of Triton always faces Neptune. Triton also has a backward orbit The surface of Triton is most likely ice and rock with possibly a liquid core. Triton also has nitrogen geysers, caused by gas below the poles, which expand and erupt when heated by the sun.

Pluto- A Dwarf Planet Why Dwarf Planets? Pluto with its moon Charon, which is almost a big a Pluto. Why Dwarf Planets? There are 3 Dwarf Planets in our Solar System; Pluto, Eris (found in the Kupier Belt) and a very large asteroid called Ceres. What is a Planet? In 2006 the International Astronomical Union define a planet as an object that orbits the sun with sufficient mass and gravity. Dwarf Planets orbit the sun but do not clear their “neighborhood” and they are not a moon(satellite)

Pluto (The Dwarf Planet) Average distance from Sun- 3.8 billion miles Temperature- -382°F Diameter- 1,432 miles 1 Moon- Charon (Diameter of 730 miles) Atmosphere- 99.97% Nitrogen Rotation= 6.38 days Revolution= 248.6 years Gravity- 1/8 that of Earth Orbit- Pluto has a more elliptical and titled orbit, one of the reasons its lost identification as a planet. This tilted orbit sometimes allows it to be closer to the sun than Neptune, making Neptune the further most planet. Eccentricity: .25

Other Large Objects in Kupier Belt Other Dwarf Planets: Other Large Objects in Kupier Belt Ceres Ceres-located in the Asteroid Belt. It was discovered in 1801. Some still consider Ceres just a very large asteroid rather than a dwarf planet 2005 FY9- red Xena-bluish color, 52 AU’s away Sedna- Red, 67 AU’s, .85 eccentricity and 10,000 to orbit the Sun! Quaoar- Blue-gray Eris Eris was discovered in 2003, this caused the controversy of Pluto because these two objects were the same size White in color and 97 AU’s away Has 1 moon Eccentricity is .43