MARS EDUCATION PROGRAM Looking for Life Adapted from “Destination Mars” NASA JSC Brian Grigsby School of Earth and Space Exploration ASU Mars Education

MARS EDUCATION PROGRAM Wall Street Journal August 3, 2007 In a Strange Universe, We Stick to Search For Familiar Life “Would we recognize (life) if we ever did chance upon alien life?...It is clear that nothing would be more tragic in the American exploration of space than to encounter alien life without recognizing it.”

MARS EDUCATION PROGRAM Working with data… What is life? How do we define it? Where can life survive? How does this affect our search for life?

MARS EDUCATION PROGRAM Activity Objectives Students will: Form an operational definition of life Conduct a simulated experiment with soil samples State relationships between the soil samples using their operational definition of life Make an inference about the possibility of life on Mars based upon data obtained

MARS EDUCATION PROGRAM National Science Standards (K-4) As a result of their activities in grades K-4, all students should develop an understanding of: –CONTENT STANDARD A: Abilities necessary to do scientific inquiry Understanding about scientific inquiry –CONTENT STANDARD C: The characteristics of organisms Life cycles of organisms Organisms and environments –CONTENT STANDARD G: Science as a human endeavor

MARS EDUCATION PROGRAM National Science Standards (5-8) As a result of their activities in grades 5-8, all students should develop an understanding of: –CONTENT STANDARD A: Properties and changes of properties in matter –CONTENT STANDARD B: Properties of objects and materials –CONTENT STANDARD C: Structure and function in living systems Diversity and adaptations of organisms –CONTENT STANDARD G: Science as a human endeavor

MARS EDUCATION PROGRAM National Science Standards (9-12) As a result of their activities in grades 9-12, all students should develop an understanding of: –CONTENT STANDARD A: Abilities necessary to do scientific inquiry Understanding about scientific inquiry –CONTENT STANDARD B: Structure of atoms Structure and properties of matter Chemical reactions Interactions of energy and matter –CONTENT STANDARD C: The cell Molecular basis of heredity Biological evolution Interdependence of organisms Matter, energy, and organization in living systems Behavior of organisms –CONTENT STANDARD G: Science as a human endeavor Nature of scientific knowledge Historical perspectives

MARS EDUCATION PROGRAM Characterize the Geology Determine if Life Ever Arose on Mars Characterize the Climate Prepare for Human Exploration WATERWATER When? Where? Form? Amount? MARS SCIENCE STRATEGY: Follow the Water! MARS SCIENCE STRATEGY: Follow the Water! Common Thread LIFE CLIMATE GEOLOGY HUMAN

MARS EDUCATION PROGRAM 1970’s—Viking Landers Science instruments: –Biology instrument, gas chromatograph/mass spectrometer, X-ray fluorescence spectrometer, seismometer, meteorology instrument, stereo color cameras, physical and magnetic properties of soil, aerodynamic properties and composition of Martian atmosphere with changes in altitude Results: Inconclusive

MARS EDUCATION PROGRAM Fast forward 30 years…2007 Phoenix Mars Lander Launch date: August 2007 Landing: May 2008 Science Instruments: –Surface Stereo Imager (SSI) –Robotic Arm (RA) –Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) –Robotic Arm Camera (RAC) –Thermal and Evolved Gas Analyzer (TEGA) –Mars Descent Imager (MARDI) –Meteorological Station (MET)

MARS EDUCATION PROGRAM Phoenix Lander: Science Objectives Study the history of the ice as written into the soils. Understand the geomorphology through imaging. Study the weather throughout the northern summer. Evaluate if the martian soils can potentially support life.

MARS EDUCATION PROGRAM Activity focus points: Evaluate if the martian soils can potentially support life. On Earth, energy, liquid water, and carbon material are the basic ingredients needed by all life.

MARS EDUCATION PROGRAM Evaluate if the martian soils can potentially support life. Ultraviolet radiation, oxidants, and other poisons would make the soil uninhabitable.

MARS EDUCATION PROGRAM Background Information We usually recognize something as being alive or not alive. But the signs of life or previous life are not easy to determine. Scientists must establish criteria to work with in their research. How then, do we identify/define life? Can you identify the living things in this picture? Yeast Sand Sugar

MARS EDUCATION PROGRAM Definition of Life Consider a bear and a chair: –Both have legs, but only one can move on its own –The other would need a motor to get around –Indicators for life: Locomotion, respiration, etc.

MARS EDUCATION PROGRAM Another example would be a tree and a light pole –We know that a light pole can not reproduce, it is made by humans. –But a tree produces seeds, that may produce more trees –The tree also takes in nutrients and gives off gasses and grows.

MARS EDUCATION PROGRAM Subtle, but fundamental signs of life: Metabolic processes that show chemical exchanges which may be detected in some sort of respiration or exchange of gases or solid materials Some type of reproduction, replication or cell division Growth Reaction to stimuli

MARS EDUCATION PROGRAM Operational Definition of Life Part 1 (5 min) Using the “Fundamental Criteria for Life Chart”, come up with characteristics that make an individual item alive or not alive.

MARS EDUCATION PROGRAM Its Alive! Part 2 Objective –You will examine 3 different soil samples and look for signs of life based on the criteria from Part 1. Materials –Soil samples –Warm/hot water –Magnifying lens

MARS EDUCATION PROGRAM Procedure (teams of 3) 1.Each team has been given a set of soil samples, but no one knows if there is anything alive in them. 2.Using the craft sticks, place a couple of scoops into the paper cup 3.From the sample in the cup, place a small amount onto a flat white surface and observe with a hand lens, then record your data on Data Chart I. 4.Make careful observations and check for indications of living material in them, based on your criteria from Part A. 5.Observe all 3 samples 6.You can smell and touch the samples but do not taste them. 7.Once you have observed the samples, place a small amount of water into the paper cup, just covering the sample. 8.Record any changes in the sample on Data Chart II

MARS EDUCATION PROGRAM Analysis / conclusion Which samples showed indication of activity? Does that mean there is life in those samples? Are there other explanations for activity in those samples? By applying the fundamental criteria for indicating life we developed, which sample contained life?

MARS EDUCATION PROGRAM Sample contents Sample A: Soil and Sugar Sample B: Soil, Sugar and Yeast Sample C: Soil Sugar and Alka-Seltzer Sample A: Physical Reaction (sugar Dissolves in the sample) Sample B and C: Chemical reaction Sample B sustains long-term activity

MARS EDUCATION PROGRAM Are there other tests that would detect life in Sample B? –(there might be microbes in the soil that would grow on a culture medium)

MARS EDUCATION PROGRAM Extensions Have students answer the following question: –What do you think alien life would look like?