Sp21_Activity1_Geoscience-student

Plenge GEOL101 Sp21 Name_____Poojha Palle_______ Activity 1: Intro to Geoscience (Individual Completion Activity) -------------------------------------------------------------------------------------------------------------------------------------------------- After completing this activity individually, you will have a group assessment in class on Wednesday. Bring this document to Wednesday’s synchronous Zoom class session to work with your teammates. -------------------------------------------------------------------------------------------------------------------------------------------------- Learning objectives: Students will be able to:  Differentiate between hypotheses and predictions and generate examples of each.  Differentiate between deductive and inductive reasoning  Identify types of data sets (e.g., observational vs. modeled) needed to test a given hypothesis  Differentiate between the heliocentric and geocentric model of the solar system and explain how the retrograde motion of Mars was explained in each.  Define Kepler’s laws and identify how these laws allowed mathematical models to better approximate observational data Background: Here are some definitions written out for each term: u Hypotheses are proposed answers or explanations to scientific questions , based on background knowledge/prior data. Hypotheses are used as starting places for further investigation. They must be testable and falsifiable to be useful in scientific investigations. u Example: “The Moon has different phases because the half of the Moon that is lit by the Sun is not always facing the Earth.” u Predictions are the expected results of tests/experiments or natural events based on hypotheses… often (but not always) an if/then statement. u Example: “If the Earth is between the Moon and the Sun, then the Moon is visible from Earth as a full moon” u Models can be used to help make predictions, or to test if a prediction is correct or not. u Example: Visual models illustrating how the moon would look from the Earth based on the position of the Sun, Earth and Moon, e.g.: u https://ccnmtl.github.io/astro-simulations/lunar-phase-simulator/ u https://www.youtube.com/watch?v=wz01pTvuMa0 u Inductive Reasoning occurs when scientists draw general conclusions from specific observations. u Observations are used to generate hypotheses, which may be confirmed or rejected by additional observations/experiments. u Example: “Three massive hurricanes caused large amounts of damage to the U.S during the 2005 hurricane season: Hurricane Katrina (902 mbar pressure), Hurricane Rita (898 mbar pressure), and Hurricane Wilma (882 mbar pressure). Based on this evidence, we conclude that hurricanes with air pressures of ~900 mbar will cause large amounts of damage.” u Think of this as “trial-and-error” style reasoning. Scientists who use inductive reasoning may not be testing a specific hypothesis when they recognize a pattern in observations that leads them to a new hypothesis. u Deductive Reasoning occurs when scientists use a general principle/hypothesis to reach a conclusion u A general principle/hypothesis is used to obtained to get specific results; the hypothesis may be confirmed or rejected based on whether or not these results are obtained. u Example: “All hurricanes form as low-atmospheric-pressure systems over the ocean. Therefore, Hurricane Katrina, Hurricane Rita, and Hurricane Wilma were all low-pressure systems.” u Think of this as reasoning by drawing conclusions based on logic and previous knowledge/assumptions. Part 1: Hypotheses, Models, Predictions. Inductive and Deductive reasoning.

Corresponding Lecture materials: Lecture 1&2 Corresponding book chapter: Chapters 1 Other required materials : Definitions on previous page, animations linked within Part 1 questions. -------------------------------------------------------------------------------------------------------------------------------------------------- 1. Complete this Venn diagram contrasting scientific models, hypotheses, and predictions. There will NOT be an equal number of answers in each section of the diagram. 2. Practice generating hypotheses and predictions for the scientific questions below. You do not have to come up with the correct answer: you just want to practice structuring the statements. a. Question 1: Why do we have seasons on Earth? i. Hypothesis : One statement answer, should have a “why” component, e.g., “we have seasons because…..” We have seasons on Earth because the Earth rotates on an axis, causing different areas to be at varying distances from the sun at different times of the year. ii. Data needed: What kinds of data would we need in order to test our hypothesis? We would need temperature data from countries in the northern and southern hemisphere to distinguish the tilt of the Earth’s axis. We would also need agricultural and climate data to see how crops react to weather during different times of the year. iii. Prediction : What should the data show if our hypothesis is correct? The data would show that for around 6 months, the northern hemisphere will be colder while the southern hemisphere is warmer and vice versa for the next six months. It would show that for both hemispheres, temperatures stay high and stay low consistently during these six months. b. Question 2: Why do lunar eclipses occur? i. Hypothesis : One statement answer, should have a “why” component, e.g., “we have seasons because…..” 1 Model Hypothesis Prediction A. Proposed explanation to a scientific question B. Use data (observations) + prior knowledge C. Expected future condition, deduced from a hypothesis D. Used to collect or organize data to test a hypothesis E. “The Moon has different phases because sometimes parts of the moon are covered up by Earth’s shadow” F. “If the Earth is between the Moon and the Sun, then the Moon will not be visible.”

This statement is deductive because a hypothesis/theory is used to conclude that larger planets should have more moons than smaller planets. “Large planets have a stronger gravitational force” is a hypothesis that has been reached with the help of planetary data. b. The coelacanth is an ancient species of fish: Fossil evidence of this fish was first found in Cretaceous-aged rocks in 1836. Scientists examined other rock samples and modern waters from 1836-1936 without finding any more fossils or live specimens. Therefore, this fish is extinct. (circle one) INDUCTIVE / DEDUCTIVE. Justify your answer. This statement is inductive because the conclusion—the coelacanth species of fish is extinct— is based off of observations from fossilized data found from the Cretaceous-aged rocks in 1836. Part 2: Retrograde motion (questions on next page) Corresponding Lecture materials: Lecture 1&2 Corresponding book chapter: Chapters 1 Other required materials : Animations and webpages linked below, which re-iterates and adds to class notes.  https://www.youtube.com/watch?v=hOjrPcD6Iuc  http://www.pas.rochester.edu/~blackman/ast104/retrograde7.html , read all  http://www.pas.rochester.edu/~blackman/ast104/aristotle8.html , Sections: “Epicycles and planetary motion, more sophisticated epicycles: The Ptolmaic Universe”  https://www.pas.rochester.edu/~blackman/ast104/copernican9.html , read all but “Been there; done that…” 5. Read the information on the second link given in the list above. Did Aristotle use deductive or inductive reasoning? (circle one) INDUCTIVE / DEDUCTIVE . Justify your answer. I would say he used deductive reasoning, but the theories and hypotheses he based his conclusion on were unfounded. Because Aristotle was also a philosopher, he based his theory of uniform circular motion on the Earth being the center of the universe. However, there were many ways to prove that this theory was unreasonable. 6. Can the geocentric solar system model explain the retrograde motion of Mars? (circle one) a. Yes, if we assume that the Earth and Mars orbit at different speeds. b. Yes, if we assume that the orbit of Mars is closer to the Sun than Earth’s orbit is c. Yes, if we assume that the orbit of Mars incorporates epicycles d. No explanation for the retrograde motion of Mars was incorporated into geocentric model 7. Can the heliocentric solar system model explain the retrograde motion of Mars? (circle one) a. Yes, if we assume that the Earth and Mars orbit at different speeds. b. Yes, if we assume that the orbit of Mars is closer to the Sun than Earth’s orbit is c. Yes, if we assume that the orbit of Mars incorporates epicycles d. No explanation for the retrograde motion of Mars was incorporated into heliocentric model 3

8. Sometimes incorrect models still have some predictive power, e.g., both the geocentric and heliocentric solar system models could calculate approximate positions of the planets. How can scientists determine which model is correct in cases like this? Models can have predictive power, but they cannot explain everything. Geocentric models could only explain direct motion, while heliocentric models explained retrograde motion as well. This in itself proved that heliocentric was more accurate than geocentric. As scientists narrowed the number of accurate theories, it became easier to derive a correct model of the solar system. 9. Why was the heliocentric solar system an example of deductive reasoning when it was first proposed? (circle one) a. This model was a conclusion drawn from a series of observations that could not be explained any other way b. Mathematical models based on heliocentric theory could predict the movement of planets with some accuracy c. Scientists started with the assumption that the solar system was heliocentric. Results from modelling indicated that this assumption was reasonable. 4