Nancy Krajcar (Olympic High School) and Tom Collett (Newark Memorial High School)

Is Earth Doomed To A Catastrophic Collision?

Learning Objectives (Science Standards)High School: Earth Science 1.f. & 1.b.1. Astronomy and planetary exploration reveal the solar system’s structure, scale, andchange over time. As a basis for understanding this concept:•Students will model cratering to explain how the Moon’s surface represents a sequence of craters from impact events.•Students will model the effects of surface weathering of crater structures on Earth and infer the frequency of impacts on Earth.•Students will diagram 4 major impact sources and link impact cratering to normal accretion processes at the formation of the solar system.•Students will compare data from various Earth craters to distinguish the impact crater that caused mass extinctions at the end of the Cretaceous.•Students will formulate and describe impact risks.•Students will formulate and communicate their own evidence based opinion of NEO monitoring or mitigation funding to government representatives. PROCESS SKILLS(I & E Standards)Students will: d. Formulate explanations by using logic and evidence. g. Recognize the usefulness and limitations of models and theories as scientific representations of reality. i. Analyze the locations, sequences, or time intervals that are characteristic of natural phenomena (e.g., relative ages of rocks, locations of planets over time, and succession of species in an ecosystem). m. Investigate a science-based societal issue by researching the literature, analyzing data, and communicating the findings.

What are impactor sources in our Solar System, and has Earth been hit often in the past?

Key Lessons and ActivitiesEngagement We will use NASA imagery of the Moon and Earth to encourage students to explain how craters may have formed and weathered. They will answer the question: What is the dominant feature of the Moon’s surface? We will incorporate clickers or whiteboards to pose thought provoking questions.Exploration Students will determine that Moon’s surface was repeatedly struck in the past by a variety of celestial objects.Students will evaluate craters on the Earth and determine which crater likely caused the KT mass extinction.Explanation We will teach about impact craters and the objects that form them. Sources of past and future impactFrequency and effects of impactsCurrent detection and mitigation programsExtension Students will use NASA images to determine the relative ages of impact craters. Students will model and analyze potential impact events on Earth using Near Earth Object (NEO) data with online impact calculators.

English Language Support•Direct Vocabulary Instruction •Use of groups/pair shares and rehearsal time before responding•Faux random questioning•Use of visuals•Use of manipulatives•Graphic organizers •Sentence starters •Format frame including outline to write expository solution that include a main idea and detailing evidence.

21st Century Skills•Grasping and using printed information•Technology literacy•Time management•Critical thinking and problem solving•Speaking to be understood•Logically grasping and thinking through issues•Getting ideas across in writing

Capstone Project Students will formulate and communicate their own evidence based opinion of NEO monitoring or mitigation funding to government representatives.

Implementation Plan and Next StepsWill need to modify the impact lab, create a write-up for the impact calculator activity, create two PowerPoint lessons, and establish rubrics.Will meet two times to finalize project. Preliminary implementation will be during October 2010.

Resources•NASA mission websites and imagery for past, current and future•Exploring Meteorite Mysteries An Educators Guide with Activities for Physical and Earth and Space Sciences http://ares.jsc.nasa.gov/education/activities/expmetmys/expmetmys.htm•Exploring The Moon An Educators Guide with Activities for Physical and Earth and Space Sciences http://ares.jsc.nasa.gov/Education/Activities/ExpMoon/ExpMoon.htm•Impact calculator created by Edward Gomez & Yon Yardley http://simulator.down2earth.eu/•Impact calculator created by Dr. Douglas P. Hamilton and students at U. Maryland.http://janus.astro.umd.edu/astro/impact/“Asteroid” NOVA video clip on near misshttp://www.pbs.org/wgbh/nova/space/asteroid.html

Essential Question/Problem

Is Earth doomed to a catastrophic collision ? •Throughout history, the

Earth and Moon have been impacted repeatedly.•Weathering, erosion, and tectonic activity have erased most impact evidence from Earth’s surface.•Impacts have been and continue to be a natural planetary process.

Instructional Case OrganizationSpecific questions that will help to answer the generative question: What processes have shaped the surface of our Moon and the Earth?

•There are four sources of potential impactors: Near Earth Objects (NEO), the asteroid belt, Kuiper belt, and Oort cloud.•KT impact event is believed to be the cause of an extinction that eliminated 75% of the species from Earth.

Should society be taking action to mitigate impact risks and is it worth the cost?

•The probability of a devastating impact in normal human time scale is low.•the potential destruction of such an impact would be catastrophic to human civilization.

•There are over 1,000 potentially hazardous asteroids.•Interplanetary objects are potential impactors in the long term due to orbital perturbations.•Earth gets hit all the time!-Pea size=10/hour-30m=1/100 yrs (destroy city) -2km=1/500,000 yrs (Earth catastrophe)

Is Earth in danger from impacts now?

Evaluation Students will do quick writes, answer questions using clickers, complete lab reports, and write letters to government representatives (see capstone project).

Comet Hale-Bopp

Barringer Crater

The Moon