Our Solar System.

Astronomical unit is the distance between the Earth and the Sun X 10

The planets are not at a constant distance away from the sun Perihelion is when a planet is closest to the sun Aphelion is when a planet is furthest away from the sun June 6 th Jan 6th

The Sun: Our Special Star

The Sun: Activity Sunspot cycle 11.2 years

The Planets

My Mercury Very Venus Educated Earth Mother Mars Just Jupiter Served Saturn Us Uranus Nachos Neptune

Inner or rocky planets Which ones are inner planets? Which ones are inner planets? Mercury Mercury Venus Venus Earth Earth Mars Mars Have solid, rocky surfaces Have solid, rocky surfaces Closer to the sun Closer to the sun

Mercury Period of revolution= 88 days Period of rotation= 58 days Diameter= 4880 km “Faster than a speeding bullet”

More about… Mercury Closest planet to the sun No moons Essentially it has no atmosphere, what little atmosphere that does exist is oxygen and sodium Daytime temperature is about 427 o C, night time temperatures are about -173 o C it has the greatest day-night temperature difference of all planets it has the greatest day-night temperature difference of all planets Surface is rocky and cratered, there is evidence that lava once flowed on the surface

Venus Diameter= 12,104 km Period of revolution= 225 days Period of rotation= 243 days “Greenhouse in the Sky”

Venus continued  2 nd planet from the sun  It is the brightest planet in Earth’s nighttime sky  No moons  Atmosphere is CO 2  Has a thick cloud cover which prevents observers from seeing the surface  greenhouse effect  Daytime temperatures are 480 o C (hot enough to melt lead!) Night-time temperatures are -33 o C  Venus has similarities to Earth like diameter, mass, and density  No magnetic field

Earth Diameter= 12,756 km Period of revolution= 365 days Period of rotation= 24 hours

Earth 3 rd “rock” from the sun 3 rd “rock” from the sun Has 1 natural satellite, the moon Has 1 natural satellite, the moon Contains lots of life-supporting water Contains lots of life-supporting water Water occurs as gas, liquid, and solid Water occurs as gas, liquid, and solid Oxygen-rich atmosphere Oxygen-rich atmosphere Atmosphere is made of oxygen and nitrogen

Mars Diameter= 6974 km Period of revolution= 1.88 years Period of rotation= 24.5 hours “The Rusty Planet”

More about… Mars 4 th planet from the sun 4 th planet from the sun High iron content in the soil is responsible for its reddish surface color High iron content in the soil is responsible for its reddish surface color 2 irregularly shaped moons, Phobos and Deimos 2 irregularly shaped moons, Phobos and Deimos thin atmosphere thin atmosphere largest mountain which is a volcano, Olympus Mons largest mountain which is a volcano, Olympus Mons Surface has dried river and lake beds which suggest that liquid water once existed on Mars Surface has dried river and lake beds which suggest that liquid water once existed on Mars “dry ice” CO 2 exists at each pole, which covers “water” ice “dry ice” CO 2 exists at each pole, which covers “water” ice Low temps= -130 o C, high temps= -31 o C Low temps= -130 o C, high temps= -31 o C No magnetic field No magnetic field

The outer planets are… JupiterSaturnUranusNeptune Larger in size Made of gases or liquids All gas giants have rings Also known as “gas giants”

Jupiter Diameter=142,700 km Period of revolution= years Period of rotation= 10 hours “The planet that was almost a star”

Jupiter continued 5 th from the sun Largest planet Hydrogen and Helium make up most of the atmospheric gases Has the shortest “day” in the solar system “The Great Red Spot”, a storm, has been rotating around Jupiter for more than 300 years 16 satellites: 4 major moons Io (has volcanic activity), Europa, Ganymede, and Callisto Scientists believe if Jupiter would have grown larger during the formation of the solar system it could have been a star High temps= 29,700C, low temps= -95C

Saturn Diameter= 120,000 km Period of revolution= years Period of rotation= 10.5 hours “A world of many rings”

More about …Saturn  6 th planet from the sun  Atmosphere is mainly Hydrogen and Helium  18 known satellites= Titan is a major moon  Broader and brighter ring system than the other gas giants  Rings are made of pieces of rock and ice (size ranges from microscopic to the size of a house)

Uranus Diameter= 50,800 km Period of revolution= years Period of rotation= 16.8 hours “A Planet on its Side”

Uranus… continued  Atmosphere of hydrogen, helium, and methane  The planet seems tipped because its axis is tilted  Its rings appear to circle the planet from top to bottom  15 moons, 2 are geologically active= Miranda and Ariel

Neptune Diameter= 48,600 km Period of revolution= years Period of rotation= 16 hours “The Mathematician’s Planet”

more about… Neptune more about… Neptune Due to Uranus’ unusual orbit, scientists calculated that there must be another planet beyond Uranus, Neptune was discovered exactly where it had been calculated to be Due to Uranus’ unusual orbit, scientists calculated that there must be another planet beyond Uranus, Neptune was discovered exactly where it had been calculated to be Huge clouds of methane float in an atmosphere of hydrogen and helium Huge clouds of methane float in an atmosphere of hydrogen and helium 8 moons, Triton is 4 th largest moon in the solar system 8 moons, Triton is 4 th largest moon in the solar system

Dwarf Planets Pluto hit the headlines in 2006 when it was demoted from a planet to a dwarf planet by the International Astronomical Union. While most astronomers agreed with the new classifications, some disagreed and still refer to Pluto as the ninth planet. Ceres is located in the asteroid belt between the orbits of Mars and Jupiter. It was discovered in 1801, well before Pluto and 45 years before Neptune. Ceres was considered a planet for around 50 years before being reclassified as an asteroid and once again in 2006 as a dwarf planet. MarsJupiterNeptuneMarsJupiterNeptune Eris was discovered in 2005 and was referred to as the tenth planet until it was reclassified in It is the largest of the dwarf planets. Makemake was discovered in 2005 and the third largest dwarf planet behind Eris and Pluto. Haumea was discovered in 2004 and named a dwarf planet in a dwarf planet in 2008.

Kuiper Belt and Oort Cloud: Home of Comets

Asteroids Fragments of rock that orbit the sun Millions are found in the asteroid belt between Mars and Jupiter

Comets Small icy bodies that orbit the sun Comets can come from the Kuiper Belt that is AU away or the Oort Cloud that is more than 100 AU away

Meteoroids, Meteors, and Meteorites

Is there more to be discovered?