2. Harcourt Science Unit D Chapter 3 Mrs. Strand Lockwood Middle School

3. Chapter Project

4. Solar System Terms to know –Planetary system –Asteroid –Meteoroid –Comet –Astronomical unit –Light year

5. Organization of the Solar System There have been various models over time. There are two basic theories –Geocentric –Heliocentric There are two basic orbital patterns –Elliptical –Circular

6. Structure of the Solar System Sun Planets Moons Asteroids Meteoroids –M–Meteors –M–Meteorites Comets –W–What is the difference between a planet and a moon? http://images.google.com/imgres?imgurl=http://www.qrg.northwestern.edu/projects/vss/ docs/media/space- environment/gaspra.gif&imgrefurl=http://www.qrg.northwestern.edu/projects/vss/docs/s pace-environment/1-asteroid-planetiod- meteoroid.html&h=440&w=523&sz=100&hl=en&start=3&tbnid=BDqORudhAqNsvM: &tbnh=110&tbnw=131&prev=/images%3Fq%3Dmeteoroid%26svnum%3D10%26hl%3 Den%26lr%3D%26sa%3DG http://images.google.com/imgres?imgurl=http://starchild.gsfc.nasa.gov/Image s/StarChild/solar_system_level2/fireball_big.gif&imgrefurl=http://starchild.g sfc.nasa.gov/docs/StarChild/solar_system_level2/peekskill.html&h=270&w= 468&sz=52&hl=en&start=8&tbnid=pFWbhRdf87zYMM:&tbnh=74&tbnw= 128&prev=/images%3Fq%3Dmeteoroid%26svnum%3D10%26hl%3Den%26 lr%3D%26sa%3DG http://images.google.com/imgres?imgurl=http://science.nasa.gov/images/halebopp.jpg&i mgrefurl=http://science.nasa.gov/newhome/headlines/ast16nov98_3.htm&h=333&w=18 4&sz=20&hl=en&start=17&tbnid=Ku0KHoUFvLAaRM:&tbnh=119&tbnw=66&prev=/ images%3Fq%3Dmeteoroid%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DG http://images.google.com/imgres?imgurl=http://www.fregger.com/space_content/8halley- comet.jpg&imgrefurl=http://www.fregger.com/pictures.html&h=600&w=800&sz=48&hl=en&start =6&tbnid=JFAv4ExC3iWa1M:&tbnh=107&tbnw=143&prev=/images%3Fq%3Dcomet%26svnum %3D10%26hl%3Den%26lr%3D%26sa%3DG

7. Astronomical Units and Light-Years 93,000,000 miles or 150,000,000 KM distance from sun to earth = 1 AU Usually used to measure distances between planets 5,900,000, 000 miles or 9,500,000,000 KM distance from the sun to the nearest star Light years usually used To measure distance to stars

8. Cycles of Planets Terms to know: –Rotation –Axis –Revolution –Orbit –Ellipse

9. Planets rotate on their axis Each day, 24 hours on Earth, is one rotation. Each year, 365 1/4 days on Earth is one revolution. http://csep10.phys.utk.edu/astr161/lect/solarsys/revolution.html

10. Orbits Elliptical –Perihelion –Aphelion How planets move in their orbits –Property of inertia http://www.space.com/bestimg/?guid=4499b3949c8db&cat=strangest http://www.yourdictionary.com/images/ahd/jpg/A4perihe.jpg

11. Wobbly planets Precession of the Earth How do we even know this happens? –The North star changes from time to time. See chart pg D90

12. Why do planets have seasons? Terms to know: –Season –Axial tilt

13. Earth Seasons Are we pointing towards the sun or away from it? –Autumnal Equinox Dates? –Winter Solstice Dates? –Vernal Equinox Dates? –Summer Solstice Dates? Hmmmmm… How does the tilt of the earth affect temperature?

14. What… Still looking to the stars for answers?

15. Why are seasons on Mars so much more extreme? Angle of axis Shape of orbit Do you think there are planets with NO seasons? Why or why not?

16. Phases of the moon Terms to know: –Phases –First quarter –Third quarter –Waning –Waxing http://images.google.com/imgres?imgurl=http://www.wisegorilla.com/images/solarsystem/MoonPhases.gif&imgrefurl=htt p://www.wisegorilla.com/images/solarsystem/solarsystem.html&h=540&w=720&sz=41&hl=en&start=11&tbnid=9sM05 oBriZfI2M:&tbnh=105&tbnw=140&prev=/images%3Fq%3Dmoon%2Bphases%26svnum%3D10%26hl%3Den%26lr%3 D%26sa%3DG

17. Phases of the moon Have you ever wondered why the moon appears larger in the early evening, than later at night?

18. http://radiojove.gsfc.nasa.gov/images/phases_of_moon.gif