Transcript C1_Intro
In a Congressional hearing of the U.S. Armed Services Committee In March, 2010, elected Congressman from Georgia Hank Johnson, when asking about the potential of a U.S. military troop buildup on the island of Guam, said “I am afraid that the island will become so populated that it will tip over…and capsize.” In a Congressional hearing of the U.S. Armed Services Committee In March, 2010, elected Congressman from Georgia Hank Johnson, when asking about the potential of a U.S. military troop buildup on the island of Guam, said “I am afraid that the island will become so populated that it will tip over…and capsize.” Admiral Robert Willard replied: “We don’t anticipate that. The Guam population, I think, is currently about 175,000. And again, with 8000 marines and their families, its an addition of about 25,000.” In a Congressional hearing of the U.S. Armed Services Committee In March, 2010, elected Congressman from Georgia Hank Johnson, when asking about the potential of a U.S. military troop buildup on the island of Guam, said “I am afraid that the island will become so populated that it will tip over…and capsize.” Admiral Robert Willard replied: “We don’t anticipate that. The Guam population, I think, is currently about 175,000. And again, with 8000 marines and their families, its an addition of about 25,000.” What is wrong with this discussion?!?!? Is this how islands works? Mariana Volcanic Arc: Guam bathymetry: Big Idea #1: Earth scientists use repeatable observations and testable ideas to understand and explain our planet. Big Idea #2: Earth is 4.6 billion years old. Big Idea #3: Earth is a complex system of interacting rock, water, air and life. (A SYSTEM OF SYSTEMS!) Big Idea #4: Earth continuously changing. Big Idea #5: Earth is the water planet. Big Idea #6: Life evolves on a dynamic Earth and continuously modifies Earth. Big Idea #7: Humans depend on Earth for resources. Big Idea #8: Natural hazards pose risks to humans. Big Idea #9: Humans significantly alter the Earth. Q. What is the Age of Universe? Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? A. Intensity vs. Red shift of galaxies Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? A. Intensity vs. Red shift of galaxies Q. What is the Age of the Solar System? Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? A. Intensity vs. Red shift of galaxies Q. What is the Age of the Solar System? A. 4.56 Ga Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? A. Intensity vs. Red shift of galaxies Q. What is the Age of the Solar System? Q. How do we know this? A. 4.57 Ga Q. What is the Age of Universe? A. About 13.7 billion years (Ga) Q. How do we know this? A. Intensity vs. Red shift of galaxies Q. What is the Age of the Solar System? Q. How do we know this? A. 4.57 Ga A. Radiometric dating of meteorites Q. How large is the Solar System? If the Earth were the size of a penny, how large would the diameter of the solar system be? (Radius of Kuiper Belt is ~50 AU) Q. How large is the Solar System? If the Earth were the size of a penny, how large would the diameter of the solar system be? (Radius of Kuiper Belt is ~50 AU) 22.3 km (14 mi) --- from here to Chesterfield Q. How large is the Solar System? Diameter = 1.5 x 1010 km = 15 billion km If the Earth were the size of a penny, how large would the diameter of the solar system be? (Radius of Kuiper Belt is ~50 AU) 22.3 km (14 mi) --- from here to Chesterfield Q. How large is the Milky Way galaxy? If the solar system was the size of a penny, how large would the diameter of the Milky Way galaxy be? Q. How large is the Milky Way galaxy? If the solar system was the size of a penny, how large would the diameter of the Milky Way galaxy be? 1400 km --- from here to Pittsburgh Q. How large is the Milky Way galaxy? D = 1.1 x 1018 km If the solar system was the size of a penny, how large would the diameter of the Milky Way galaxy be? 1400 km --- from here to Pittsburgh Q. How large is the Milky Way? 120,000 light years Q. What's a light year? (3 x 108 m/s x 365.25 days x 24 hr x 60 min x 60 s = about 9.5 x 1015 m) So the Milky Way is 120,000 x 9.5 x 1015 m = 1.1 x 1021 m = 1.1 x 1018 km = 7 x 1017 mi 1.1 x 1018 km = 1,100,000,000,000,000,000 km (I have no concept of how big this is) Q. How large is the observable Universe? If the Milky Way was the size of a penny, how large would the diameter of the observable universe be? Q. How large is the observable Universe? If the Milky Way was the size of a penny, how large would the diameter of the observable universe be? 15 km --- from here to Lambert Airport Q. How large is the observable Universe? D = 93 billion light years = ~ 9 x 1023 km = ~ 1 septillion km If the Milky Way was the size of a penny, how large would the diameter of the observable universe be? 15 km --- from here to Lambert Airport Geosphere Composition of Crust (%): Weight Oxygen 47.2 Silicon 28.2 Aluminum 8.2 Iron 5.1 Moles 61.7 21.0 6.4 1.9 Volume 93.8 0.9 0.5 0.4 Composition of Whole Earth (weight %): Iron Oxygen Silicon Magnesium Nickel 35 30 15 13 2.4 Hydrosphere: 96.5% in Oceans 3.5% in glaciers, groundwater ~0% in streams, lakes, atmosphere, biosphere 71% of Earth’s surface is covered with water. If Earth were a perfect sphere, it would be covered with 2.25 km of water. Atmosphere: Composition: N2 - 78.1% O2 - 20.9% Ar 0.93% H2O - 0.1% CO2 - 0.039% (increasing) Ne 0.0018% Earth's magnetic field LOOKS LIKE there is a tilted, offset, wandering, bar magnet in its core. (But there isn’t!!) Fluid flow (convection) of liquid iron in Earth’s outer core creates the magnetic field. Magnetohydrogeodynamo The magnetosphere protects us from ionized particles of solar wind. Biosphere: Extends from the seafloor and deep crust, to the tops of mountains and the atmosphere. 3 - 300 million species; ~1.5 million identified VERY significant geological agent (Ex: atmosphere, weathering) Temperature 0ºC (~273 K) ~4000ºC ~6000ºC 3.62 Megabars “bar” 1 Pressure