Essential Lens: Analyzing Photographs Across the Curriculum
Processes of Science: Mars, a Case Study #6005 Dry Ice Gone Wild
Date: January 12, 2011
Source: NASA/JPL-Caltech/University of Arizona
Have you ever played with dry ice (with leather gloves on of course!)? Perhaps you’ve made Halloween punch? Set a spooky scene? The fun comes from the fact that dry ice goes directly from solid to vapor, unlike water ice, which melts into liquid when it gets warm.
On Mars, the seasonal polar caps are composed of dry ice (carbon dioxide). In the springtime, as the sun shines on the ice, it turns from solid to gas and causes erosion of the surface. “Spiders,” “caterpillars,” or “starbursts,” can be colloquial words for what is actually called “araneiform” terrain.
This particular example shows eroded channels filled with bright ice, in contrast to the muted red of the underlying ground. In the summer, the ice will disappear into the atmosphere, which leaves just the channels carved in the surface. This is truly Martian terrain: This type of erosion does not take place anywhere naturally on earth because our climate is too warm.
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Supplementary: Essential Lens: Processes of Science - Mars, a Case Study
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Program 1 A Closer Look (video)
This introduction to the course models the process of analyzing photographs with teachers and students. Photography historian Makeda Best discusses the Focus In method with teachers, and educator Julie Keefe employs the method with students at a photography exhibit on "light and dark." Photography curator at the Portland Art Museum, Julia Dolan discusses how she carefully selects a set of photographs to tell a larger story.
Program 2 Witness (video)
Photographs bear witness to world events and help us to learn more about people, places, and situations -- historical and present day. Middle school teacher Donald Rose guides students in analyzing photos from school integration movements of the 1960s. Documentary film producer Ken Burns weaves photographs into historical narratives to bring the past to life. Photojournalist Louie Palu's photos take us deep into mines and war zones, and engage us with the individuals who take on those tasks.
Program 3 Lives (video)
Lives explores the story of human resilience and perseverance. Middle school teacher Donald Rose uses the Migrant Mother photos by Depression-era photographer Dorothea Lange to help students understand what elements a photographer chooses to focus on to create the greatest impact. Historian Linda Gordon, biographer of FSA photographer Dorothea Lange reveals Lange's role in engaging Americans in the plight of those who were most devastated. New Orleans documentary photographers Keith Calhoun and Chandra McCormick talk about the transformation of their photographs after Hurricane Katrina and working with young photographers to preserve the city's cultural heritage.
video 4 Evidence (video)
An image can show us otherwise invisible processes, previously undiscovered life forms, and dramatic change over time. High school teacher Rima Givot engages her students with highly magnified photos of mouse muscle to study genetically modified organisms. Scientist and photomicrographer Dennis Kunkel demonstrates the fascinating process of creating photographs of the microscopic world. Environmental photographer Gary Braasch reports on his worldwide travels to document the state of the planet through repeat photography.
Program 5 Story (video)
Every photograph tells a story: of struggle, of beauty, of community and culture. Social studies teacher Kim Kanof uses photos from the Protests and Politics collection to teach about protests around in the world in 1968. National Geographic photo editor Pamela Chen details the collaborative process of creating photo-based feature stories with design director David Whitmore. Iowa photographer Danny Wilcox Frazier discusses his work documenting the residents and images of marginalized communities across the United States.