The Solar System

1. The Solar System • What is the Solar System? • “The Players” • An Overview of the Solar System • Classification • Size, density, & atmosphere • Terrestrial – Earth like • Giant (Jovian) – Jupiter like • Table 15.1 (p. 382) • AU (Astronomical Unit) = 93 million miles • Inclination to ecliptic • Period of Rotation • Period of Revolution • Mass • Relationship of distance and revolution

2. The Solar System: Terrestrial Planets • Mercury – “The Winged Messenger” • Small planet • 8th largest • Seen as a “morning star” or “evening star” • Fig. 15.3 p. 382 • Heavily cratered • Very very hot • 825 degrees F • Very very cold • -320 degrees F • Weak gravitational pull (mass) • No atmosphere • No natural satellites (moons)

3. The Solar System • Mercury

4. The Solar System: Terrestrial Planets • Venus – The “Goddess of Beauty” • Earth’s “sister planet” • Evening & Morning star • Brightest of all planets • A “blueish” color • Thick dense atmosphere • Phases • Day vs. Year • Rotates – 243 days • Revolves – 225 days • Tilt of axis (177 degrees) • Rising & setting of the Sun (west to east) • Retrograde rotation • High atmospheric pressure • 100x that of Earth • 1,070 lbs/sq. in. • CO2 (97%) • Massive “greenhouse effect” • Rains sulfuric acid

5. The Solar System • Venus

6. The Solar System: Terrestrial Planets • Mars – The “God of War” • Very Earth like • Distinct “reddish” color • Interesting features: • The plains • The “channels” • Dried river beds • Martians and other good stories • Seasonal changes • Polar ice caps • Frozen CO2 • Olympus Mons volcano • 15 mi. high • 370 mi. wide • The size of Texas

7. The Solar System: Terrestrial Planets • Atmosphere • 95% CO2 • Phobos & Deimos (The Gods of Fear & Panic) • Small in size • Irregular in shape

8. The Solar System • Mars

9. The Solar System • Olympus Mons

10. The Solar System • Phobos

11. The Solar System • Demos

12. The Solar System: Jovian Planets • Jupiter – King of the Gods • By far the largest planet in the Solar System • 318 x’s that of Earth • 11x’s the diameter • Interesting features: • Great Red Spot • 25,000 mi dia. • A Jovian storm • Colorful bands (Fig. 15.9) • 39 satellites • Galilean Satellites • Io • Erupting volcano • Europa • Callisto • Ganymede • Atmosphere • H & He • Ring structure

13. The Solar System • Jupiter

14. The Solar System • Moons of Jupiter

15. The Solar System: JovianPlanets • Saturn – God of Agriculture • Visible in the night sky • The planet with “ears” • Interesting Features: • A system of rings (Fig. 15.12 p. 391) • Pieces of frozen CO2, rock, etc. • 2nd largest planet in the Solar System • The end of the “Ancient Planets”

16. The Solar System • Saturn

17. The Solar System • Saturn – Rings edge on

18. The Solar System Titan, Saturn's largest moon, looks small next to the gas giant in this Cassini spacecraft view. Titan (3,200 miles across) is in the upper right. (USA Today – 3/5/12)

19. The Solar System: Jovian Planets • Uranus & Neptune • Twin planets • The “Ice Giants” • Atmosphere – H & He • Uranus – God of the Sky • A bit of history • Discovered in 1781 • William Hershel – a comet hunter • Neptune – God of the Sea • A bit of history • Discovered in 1846 • Adams & Leverrier • Noticed variations in orbital path

20. The Solar System • Uranus

21. The Solar System • Neptune

22. The Solar System: Lesser Members • Pluto – God of the Underworld • Discovered in 1930 • American astronomer Clyde Tombaugh • Interesting Features: • Moon discovered in 1978 • Charon • Named for the boatman who ferried dead souls across the river Styx • Very inclined orbit – 17 degrees

23. The Solar System: Lesser Members • Asteroids, Meteors & Comets • Comets • Cosmic “ dirty snowballs” • Highly eccentric orbits • Head or Coma & a tail • Tail always points away from the Sun • Force of solar wind • Between Mars & Jupiter sublimation begins • Years to complete 1 orbit • Best known • Halley’s Comet • 76 yr orbital period • Form in what is known as Oort’s Cloud • 30 AU – 1 ly • Comets give birth to meteors(Shooting Stars)

24. The Solar System: Lesser Members Bayeux Tapestry Battle of Hastings 1066 AD

25. The Solar System: Lesser Members • Asteroids • Know as the Asteroid Belt • Located between Mars & Jupiter • Vary in size • Average ~ 30 mi. • Meteoroids, Meteors, & Meteorites • Location, Location, Location • By product of comets • “Shooting Stars” • Meteor showers • Table 15.5 p. 392 • Interact (friction) with upper layers of atmosphere and burn up

26. The Solar System: Lesser Members

27. The Solar System: Leser Members • Composition of Meteors • Iron • Stone • Iron-stone

28. The Solar System: A Number Game Bode’s Rule Number Planet T.D. (AU) (0 + 4) / 10 0.4 Mercury .39 (3 + 4) / 10 0.7 Venus .72 (6 + 4) / 10 1.0 Earth 1.0 (12 + 4) / 10 1.6 Mars 1.5 (24 + 4) / 10 2.8 ????? 2.78 (48 + 4) / 10 5.2 Jupiter 5.20 (96 + 4) / 10 10.0 Saturn 9.58 (192 + 4) / 10 19.6 Uranus 19.2 (384 + 4) / 10 38.8 Neptune 30.1 (768 + 4) / 10 77.2 Pluto 39.5

29. The Solar System: It's Orgin • Protoplanet Nebular Model • 5 billion years ago • Born out of the death of ancient stars • “cosmic dust” & debris begins to concentrate in a cloud-like (Nebula) environment • Concentrated mass begins to rotate • Central area gives birth to a new star (Sun) • Cosmic debris begins to concentrate as planets begin to take shape