Lecture 2: The Solar System

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1 Lecture 2: The Solar System 1) WileyPLUS (online) registration? homework? 2) Final Exam scheduled Tuesday, December 15 (12-2) 3) iclickers assigned on Tuesday 4) Big Island Field Trip

3% This is a weekend of hiking, picnicking and learning about the worlds most active volcano at Volcano National Park. Hikes include: Thurston Lava Tube (0.

2 Fall 2015 Big Island Field Trip Everyone invited Dates: September Sign-up with GG Dept Secretary - POST 701 Cost $150 + your own round-trip plane ticket Cash or check payable to Geology Club Hike Volcano National Park, stay at Kilauea Military Camp Van transportation, lodging, and food provided EXTRA CREDIT, 3% This is a weekend of hiking, picnicking and learning about the worlds most active volcano at Volcano National Park. Hikes include: Thurston Lava Tube (0.25 mi); Kilauea Iki (4 mi); Puu Loa Petroglyphs (2 mi); Mauna Ulu summit crater (3.2 mi); Sulphur Banks (0.5 mi), Big island Candy Company; and Rainbow Falls, Hilo.

Learning Objectives (LO) 1. What we ll learn today:" 2. 1. Describe the solar nebula hypothesis" 3. " 4. 2. Understand the Sun and how it works" 5.

3 Learning Objectives (LO) 1. What we ll learn today:" Describe the solar nebula hypothesis" 3. " Understand the Sun and how it works" State the ways that Mercury, Venus, and Mars are different from Earth" Describe each of the gas giants" Define a dwarf planet"

4 The Universe

5 Our Galaxy: The Milky Way 100,000 light years across 400 billion stars Our location is not unusual

6 Formation of our Solar System Steven Hawking created this video on the formation of the Solar system

7 A nebula is a cloud of gas and dust made by an exploding star. Butterfly Nebula 3,800 light-years away Stars release energy and build elements through nuclear fusion. Nuclear fusion creates new elements. Stars burn hydrogen, becoming brighter. Eventually, stars become Red Giants and explode.

8 Solar Nebula Hypothesis Our Sun and other objects originated from a solar nebula. Crab Nebula

9 How Did the Solar System Form? The Solar Nebula Hypothesis ours began about 5 billion years ago 1. Initial cloud of interstellar gas (the solar nebula) 3. Accretion of cooler outer disk into planetesimals 2. The nebula collapses and begins to rotate 4. Gravity pulls planetesimals together to form planets

10 Planetesimal Accretion Collisions of particles of ice, gas, and dust that grew into larger planetary objects ~5 to 4.6 billion yrs ago

11 Solar Wind Push Next: A solar wind of charged particles from the Sun blew gases (volatiles) toward outer solar system Rocks and metals (heavy) remained near the Sun Gases (light) Water, methane, ammonia Helium, hydrogen - expelled to outer solar system

Our Solar System Consists Of: 1 unordinary star 8 classical planets 5 dwarf planets 240+ known satellites (moons) Millions of comets and asteroids Countless particles;

12 Our Solar System Consists Of: 1 unordinary star 8 classical planets 5 dwarf planets 240+ known satellites (moons) Millions of comets and asteroids Countless particles; and interplanetary space Earth, the Sun, and other objects in the Solar System originated at the same time from the same source and have evolved in varying ways since then

13 Our Sun : A Massive Hydrogen Bomb Held Together by Gravity

14 Our Sun Solar core is site of nuclear fusion. H is converted to He, which has less mass. Mass differential is expelled as energy (light and heat). The Sun is getting lighter through time. The Sun has enough fuel to last another 4 to 5 billion years.

Gas exerts pressure outward, balanced by force of gravity inward Dynamic Equilibrium Intense pressures fuse Hydrogen (H) into Helium (He) Nuclear explosion held together by

15 Gas exerts pressure outward, balanced by force of gravity inward Dynamic Equilibrium Intense pressures fuse Hydrogen (H) into Helium (He) Nuclear explosion held together by gravity 700 million tons of H are converted to He every second Energy is released as radiation takes 1 million years to exit the sun (!) Sunlight takes 8 min.to reach Earth Nuclear Fusion

16 The Expected Future of Our Sun The Sun is 4.6 billion years old At about 9 billion years: The sun runs out of Hydrogen fuel It begins to burn Helium It grows MUCH bigger to become a Red Giant At about 11 billion years: collapse into White Dwarf

17 Origin of the Earth 4.6 billion years ago 1 AU 2 AU 3 AU 4 AU 5 AU

18 1 AU = Astronomical Unit = distance from Earth to the Sun = 1.5 x 10 8 km Jupiter Earth SUN 1 AU 2 AU 3 AU 4 AU 5 AU

19 100,000 m or 100 km 1 AU = Astronomical Unit = 1.5 x 10 8 km

20 1 R earth = Radius of the Earth = 6378 km Jupiter Earth 1x R earth 11x R earth SUN 1 AU 2 AU 3 AU 4 AU 5 AU

21 Earth-Sized: Inner planets (+ Pluto)

22 Outer planets are much bigger

23 But the Sun is Far Larger Radius of the Sun = 700,000 km

24 Many Stars Are Much Bigger Than the Sun

25 Some Stars Are Truly Gargantuous Betelgeuse

26 Terrestrial Planets Terrestrial planets are small and rocky, with thin atmospheres, silicate & metallic shells. Main components: O, Fe, Si, Mg, Ca, K, Na, Al Mercury Venus Earth Mars

27 Gas Giant Planets Gas Giant planets are massive with thick atmospheres. Main components: He, H, CO 2, H 2 O, N 2, NH 3, CH 4 Jupiter Saturn Uranus Neptune

28 Mercury Smallest planet Silicate (SiO 2 ) shell Probable molten iron core Extreme temps: 227 o C -137 o C 2-mile high scarp

29 Venus Slightly smaller than Earth Spins slowly and backward Thick CO 2 atmosphere Runaway greenhouse: 447 C Recent volcanism Active mantle interior lava flows

30 Images From the Surface of Venus Venera-13 (1982)

31 Thin atmosphere Moderate temperatures Liquid water, life! Active tectonics & volcanism One large moon Earth

32 The Birth of Earth s Moon Collision with a another planet-sized object =

33 Moon Formation Event

34 Moon Formation Event Collision with a another planet-sized object

35 Mars Thin CO 2 atmosphere Liquid water in the past: oceans, stream beds, beaches Recent volcanism, today?

36 Big Volcanoes on Mars Entire Big Island Olympus Mons: km diameter - 27 km high - largest volcano in Solar System

37 Olympus Mons vs. Hawaii - volume ~100 x Mauna Loa

38 Images from Mars Rocky, dusty surface Stream beds?

39 iclicker Question Question: Which is Earth? (a) (b)

40 iclicker Question Which is Mars? a. (a) b. (b) (a) (b)

41 Water on Mars Water has flowed in the past But is now locked up as ice in the ground & as polar ice caps Drainage features due to short-lived melting events

42 Locked-up Icebergs? Antarctica Blocks of ice floating on a recently frozen sea covered by dust? Dust prevents evaporation

43 Asteroid Belt Between Mars & Jupiter Millions of rocky bodies Asteroids tell us composition of solar system Some asteroids cross Earth s orbit

44 A Bad Day. 65 Million Years Ago The Asteroid: ~10 km - dinosaur extinction? The Impact - Chicxulub Crater (Yucatan) km underwater crater - billions of tons of sulfur into atm. Chicxulub

45 GG 105 Lecture #20 Which is which? iclicker Question a. (1) comet; (2) asteroid; (3) meteor b. (1) meteor; (2) asteroid; (3) comet c. (1) comet; (2) meteor; (3) comet d. (1) asteroid; (2) meteor; (3) comet

46 You are looking at the tops of clouds Jupiter Does Jupiter have a hard surface? 90% Hydrogen (H), 10% Helium (He) Jupiter's Great Red Spot - A hurricane the size of 2-3 Earths lasting several centuries

Action Items for Tuesday, September 1 1. What you should know " 2. from today:" 1. Register for WileyPLUS 2. Read Chapter 2 3. Complete homework assignment #2 3. 1. Describe the solar nebula hypothesis " 4.

47 Action Items for Tuesday, September 1 1. What you should know " 2. from today:" 1. Register for WileyPLUS 2. Read Chapter 2 3. Complete homework assignment # Describe the solar nebula hypothesis " Understand the Sun and how it works" State the ways that Mercury, Venus, and Mars are different from Earth" Describe each of the gas giant planets" Define a dwarf planet"

The Solar System consists of

The Solar System consists of The Universe The Milky Way Galaxy, one of billions of other galaxies in the universe, contains about 400 billion stars and countless other objects. Why is it called the Milky Way? Welcome to your Solar