6 Law of Ellipses: explains a planet’s path around the Sun Ellipse: an oval whose shape is determined by two points (foci)The Sun is at one focus of the orbit of a planet
7 Because the planets’ orbits are elliptical, they are not always the same distances from the sun… Do you remember the word to describe the point in our orbit when we are closest to the Sun?Farthest away?
10 There are TWO types of planets in our solar system… How were you taught to remember them?
11 Planet Acronyms My Very Excellent Mother Just Served Us Nachos My Very Excellent Mother Just Served Us NoodlesMy Very Educated Mother Just Served Us Nachos
12 II. The Inner Planets (4 planets closest to the Sun) Terrestrial Planets: Earth-like (rocky)
13 A. Mercury Closest to the Sun Shortest orbit of 88 days Heavily crateredHuge temperature range 427ºC in day, -173ºC at nightMariner 10 – visited the planet in 1974 and 1979
14 B. Venus Earth’s twin (size, mass, density) Rotation direction is opposite that of other planetsPressure is 90x Earth’sHot surface(464ºC)Dense atmosphere (mostly CO2)Magellan Probe
15 C. Earth Third planet from Sun Orbital period of 365.24 days Completes one full rotation in 23 hours 56 minutesFifth largest planetLocated between the Sunand the asteroid beltOne natural satellite, themoon
16 Life on Earth is possible because… …of the Earth’s distance from the SunTemperature is warm enough for water to exist as a liquidWater occurs on Earth as a solid (ice), a liquid, or a gas (water vapor)The only known planet with the proper combination of water, temperature, and oxygen to support plant and animal life
21 D. Mars Axis is tilted like Earth’s Very thin atmosphere (mostly CO2) Olympus Mons – shield volcanoLargest known volcano inour solar system3X higher than Mt. EverestViking 1 – found evidence of water erosion
22 III. The Outer PlanetsJovian Planets: Jupiter-like gas giants
23 A. Jupiter Largest planet Fastest rotation - every 10 hours Orbital period is 12 yearsMore than 60 moonsMostly hydrogen and heliumGreat Red Spot – giant rotating storm (over 300 years long)Galileo
24 B. Saturn Average temp: -176ºC Least dense planet Orbital period is 29.5 yearsComplex system of ringsCassini Spacecraft
25 C. Uranus Rotates horizontally The ‘tipped’ planet Orbital period is 84 yearsGreenish colorMethane atmosphereVoyager 2
26 D. Neptune Orbital period is 164 years 8 moons and possibly 4 rings Upper atmosphere composed of white clouds of frozen methane (appear as bands moving between equator and poles)Great Dark Spot – huge stormSolar system’s strongest winds – exceeding 1,000 km/hr
28 A. Dwarf PlanetsAn object that, due to its own gravity, is spherical in shape, orbits the Sun, is not a satellite, and has not cleared the area of its orbit of smaller debris.
29 1. Pluto (now ‘asteroid #134340’) Late to be discovered (1930)Mostly frozen methane, rock, and iceDemoted from planetstatus to “dwarf planet” in August 2006Not always the furthest planet from the sun
30 Ceres: largest body in the Asteroid Belt Eris:largest known dwarf planet27% more massive than Pluto
33 1. Asteroids thousands orbiting the Sun between Mars and Jupiter rocky bodiesvary in diameterpitted, irregular surfaces
34 Asteroid Belt between Mars and Jupiter remains of unformed planets (planetesimals)
35 meteoroid: small bits of rocks and metal left by a comet or asteroid collision meteor: bright streak of light produced by meteoroids burning up as they enter our atmospheremeteorite: meteoroid (or part of one) that is left after it hits the Earth
36 Meteorite: meteoroid that makes it to Earth Meteor ShowerMeteorite: meteoroid that makes it to Earth“shooting stars”