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Tracking Change Over Time - Satellite Imagery


Landsat satellites capture images of Earth from space—and have since 1972! These images provide a long-term record of natural and human-induced changes on the global landscape. Comparing images from multiple years reveals slow and subtle changes as well as rapid and devastating ones. Landsat images are available over the Internet at no charge. Using the free software MultiSpec, students can track changes to the landscape over time—just like remote sensing scientists do!

The objective of the Tracking Change Over Time lesson plan is to get students excited about studying the changing Earth. Intended for students in grades 5–8, the lesson plan is flexible and may be used as a student self-guided tutorial or as a teacher-led class lesson. Enhance students’ learning of geography, map reading, earth science, and problem solving by seeing landscape changes from space.


  • Understand the concepts and applications in remote sensing. 
  • Hands on exercises to help students track landscape changes over time.
  • Compare satellite images at different points in time to detect land change.


Use this USGS webpage to go thorough the material. Click on the image on the left then you can click thorough different PDFs available.