mr. kopp’s 8 th grade earth science welcome. classroom norms, rules, and expectations note taking...
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Mr. Kopp’s 8th Grade Earth Science
Welcome
Classroom Norms, Rules, and Expectations
• Note takingName: Mr. Kopp Unit: Intro. to Earth Science Topic: What is Earth Science? Date: 9/10/15
Essential Questions:
What is Earth Science?----------------------What are the Branches of Earth Science?
Notes:
-The study of Earth and its place in space-The history of Earth and how it changes over time-------------------------------------------------------------------Earth Science is divided into Meteorology (weather), Astronomy (space), Oceanography (oceans), Geology (solid part of Earth), and Ecology (interaction between life and earth)
Connections to videos, readings, and labs:
Video: “Introduction to Earth Science”
Viewed different things an Earth Scientist might study-Galaxies-Tornadoes-Mountains
How do we think scientifically?
• 1. Make observations using your 5 senses –
• 2. Express any literal findings
• No metaphor or flowery language
• Be specific, accurate
• 3. Generate Inferences
• Using prior knowledge and experience to determine a possible explanation
• 4. Make real world connections
What are the applications of my inference to other real world events?
• 5. Write a conclusion based on factual evidence
What is the Scientific Method?
Series of steps that help guide scientific study
• Must be repeatable (recipe)• Validates conclusions
What are the steps of the scientific method?
• 1) Make an Observation in nature• 2) Identify the problem/ask a question• 3) Conduct Research• 4) Form a Hypothesis• 5) Experiment• 6) Collect/Analyze Data• 7) Draw a Conclusion• 8) Present your findings
Fact From Fiction• Scientist classify ideas based upon their ability to
PROVE their ideas using mountains of evidence and repeatable experiments
• Scientific Law – description of what scientists find happening in nature repeatedly and in the same way without exception
• Scientific Theory – a well-tested and widely accepted hypothesis
Scientific Method Keys Terms
• Data – any set of information
• Control – part of an experiment that does not change (used for comparison)
• Variable – part of an experiment that is different
Chapter 1: Introduction to Earth Science
GEOLOGY
ASTRONOMY
OCEANOGRAPHY
METEOROLOGY
ENVIRONMENTAL SCIENCE
What is Earth Science?
• The name for the group of sciences that study the Earth and its neighbors in space.
BIG BANG THEORYFORMATION OF THE UNIVERSE!
NEBULAR HYPOTHESIS
FORMATION OF THE SOLAR SYSTEM
Formation of the Earth
• NEBULAR HYPOTHESIS– the solar system formed from a giant cloud of gas and dust (nebula)
Nebular Theory Continued• 1) A nearby Giant star explodes in a supernova 5 -7
billion years ago
• 2) The material from this explosion formed a giant cloud of gas and dust – SOLAR NEBULA
Nebular Theory Continued
• 3) The cloud begins to spin due to a gravitational forces
• 4) Materials accrete (come together) at the center as the cloud flattens out
Nebular Theory Continued
• 5) Increased gravity and heat at the center causes immense amounts of material to accrete (come together) at the center (99% of all) – Fusion begins forming our sun
Nebular Theory Continued
• 6) Meanwhile, due to friction, hundreds of larger chunks are forming in the outer portions of the flattened cloud – Planetismals
Nebular Theory Continued • 7) The larger chunks grow faster than the smaller
chunks due to higher gravitational force
• 8) Only the biggest 50 - 100 or so capture all of the other chunks – Protoplanets
• 9) The biggest ones have enough gravitational pull to capture the lightest gases such as hydrogen and helium, they are also far enough away from the center (cold enough) to capture icy materials such as ammonia and methane – they become the Outer Planets or Gas Giants
(After the Sun began fusion, solar wind pushed particles outward to the outer planets causing additional growth)
• 10) The smaller, closer ones are not large enough and are too hot to capture many gases. They are called the Inner Planets or Terrestrial Planets
Nebular Theory Continued
• 11) Collisions continue on a massive scale…– A mars-sized object collides with the Earth
forming our moon
12) Many of the moons of the outer planets were captured by the planet’s gravitational pull
Nebular Theory • 1) Supernova creates giant cloud• 2) Giant Cloud (Nebula) begins to spin• 3) Nebula rotates, flattens, accretion in center (protostar)• 4) 100s of planetismals grow in the outer portion of the
disk-like cloud• 5) Fusion begins – Sun is born• 6) 50-100 Proto-planets grow• 7) Massive collisions happen - # of proto-planets decrease• 8) Inner planets remain small and rocky (due to heat)• Outer planet grow huge and gaseous (due to size and cold)• 9) moons are captured or created by explosions
Earth’s Structure
Structure of the Earth• Crust – silicon and oxygen (least
dense)
• Mantle – silicon, oxygen, and magnesium
2,885 km thick, the mantle is 82% of Earth’s volume.
• Outer Core – liquid iron and nickel2,255 km thick Density – 10-12 g/cm3
• Inner Core – solid iron and nickel (most dense)
Radius of 1,220 km. Density – 13 g/cm3
Composition of the crust
Types of CrustContinental crust – Underlies the continents. –Avg. rock density about 2.7 g/cm3. –Avg. thickness 35-40 km. –Felsic composition (light color)- Avg. rock type = Granite
Oceanic crust – Underlies the ocean basins. –Density about 3.0 g/cm3. –Avg. thickness 7-10 km. –Mafic composition (dark color)- Avg. rock type = Basalt/Gabbro
Origin of the Earth’s Atmosphere and Oceans
• While the Earth was cooling, gasses escaped from the interior (think volcanic eruptions) which became the Atmosphere and eventually rained down to become the oceans
• Source of Heat – radioactive materials, collisions of asteroids/comets
Shape of the Earth
Oblate Spheroid - • Not a perfect sphere• Flatter at the poles, bulges at
the equator• An object weighs more at the
poles (15N) than it does at the equator (14N)
• The farther an object is from the center of gravity, the less it weighs
• Copy down these Earth Facts:• Radius – avg. about 8,000 miles• Circumference• equator is 24,901.55 miles• poles is 24,859.82 miles• Mass – 5,973,000,000,000,000,000,000,000 kg• Density – 5.5 g/cm3• Period of rotation-23 hours 56 min • Equatorial rotation velocity 1,674.4 km/h (465.1 m/s)• Axial tilt 23.5°• Period of Revolution – 365 days 6 hrs 9 min• Average orbital speed 107,200 km/s