Welcome to Earth Science! Chapter 1: The Nature of Science BIG Idea: Earth Scientists use specific methods to investigate Earth and beyond. I. What is Earth Science? the study of the Earth and the universe around it… the study of Earth systems and systems in space; including weather and climate systems, and the study of nonliving things such as rocks, oceans, and planets. A. The Scope of Earth Science: 1. Astronomy: the study of objects beyond Earth’s atmosphere. The oldest branch of Earth Science. 2. Meteorology: the study of Earth’s atmosphere. Weather Forecasters Tornado Chasers 3. Geology: the study of the origin, history, and structure of Earth. 4. Oceanography: the study of the life and properties of Earth’s oceans. JACQUES COUSTEAU How much of our Earth is covered by OCEAN water? almost three-fourths! 5. Environmental Science: the study of the interactions of organisms and their surroundings. B. Earth’s Systems 1. Geosphere: the area from the surface of Earth down to its center. Three main parts: a) Crust b) Mantle c) Core Inner core Outer core 2. Atmosphere: the blanket of gases that surrounds our planet. 3. Hydrosphere: all the water on Earth. 4. Biosphere: all organisms on Earth and the environments in which they live. II. Methods of Scientists Scientific Methods: series of organized problem-solving procedures that help scientists conduct experiments. There are five (5) steps to the SCIENTIFIC METHOD: 1. State the Problem, or…Ask a Question? Observation: use of senses to gather information about the world. 2. Gather Information To investigate a problem, one must gather information… Measurement: comparing some aspect of an object with a standard unit. • inches, feet, miles ounces, pounds, tons 3. Form a Hypothesis Hypothesis: a possible solution to a problem (an educated guess) 4. Test the Hypothesis Experimentation: procedure carried out to prove or disprove a hypothesis. (a) Independent Variable: variable that you, the experimenter, changes (b) Dependent Variable: variable that is affected by changes in the independent variable; factor being measured (depends on the independent variable) (c) Constants – things that never change during the experiment Scientific Method Scenario: David read that Fox break pads and Best Break pads were the best on the market. He always used NAPA pads and believed they performed the best. He decided to test all three pads and determine which was the best. David used the same car for each set of pads. He drove 25 mph and applied the breaks at the same point on the track. David then measured how many feet the car took to stop after the breaks were applied. 1. The hypothesis was: ____________________________________ 2. The effects of the ________________(independent variable) on the __________________________________ (dependent variable). 3. List three constants: •______________________________________ •______________________________________ •______________________________________ 5. State a Conclusion After many experiments and observations, the hypothesis is either proved or disproved… Scientific FACT: - a controlled, repeatable and rigorously verified observation Scientific THEORY: an explanation based on many observations during repeated investigations - the best available explanation of a phenomenon - a hypothesis that is supported by the experiments - may change with the discovery of new data - Scientific LAW: - a theory that is proven every time it is tested describes the behavior of a natural phenomenon a ‘rule of nature’ cause of the law may not be known describes things; does not explain them accepted based on observations or experiments "Scientific laws are the evidence used to support a conclusion. Scientific theories are our best attempts at explaining the behavior of the world, in ways that can be tested by further experiment. The facts (the scientific laws) must convince us that our theory is a good explanation for what happened." Meteorite Impact Theory Explains the extinction of the dinosaurs Meteorite hit the earth 65 million years ago The impact created so much dust it blocked out the sun No sun, no plants…almost everything died Proof: Computer models Deformed quartz Iridium around the impact site III. Communication in Science lab reports graphs models