Topic outline

  • Detecting Orbital Debris Using Albedo: Index:

    Written by: Frances Dellutri, Jr. High / Intermediate Level SpacEdge Education Team and Lynne Zielinski, Manager of EIS Education                                                                                          Updated July 2022

    Title of Lesson: Orbital Debris and Albedo - Middle School
    Grade (Age) Level: Grades 5-8 (Ages 10-13)


    CCCS:   6.8.3, 6.8.7:
    NGSS:  MS-ESS1-3; MS-ESS3-2,3; MS-ETS1-1,4:  see

    Topic: Art, Astronomy, albedo, orbital debris, debris detection


    This lesson provides an introduction to orbital debris to set the stage. The concept of albedo (the ability of surfaces to reflect sunlight) is then introduced in an overview of the “Albedo Experiment,” where students will be guided through an experiment to determine the light reflecting from ‘orbiting’ objects. Concepts in this activity illustrate how albedo is employed in the study of space, specifically, in the detection of orbital debris.  

    When we look at the moon from Earth or the Earth from space, we are seeing reflected light, albedo. Earth is reflecting the sun's light energy and the moon is reflecting light energy from the sun and second hand sun reflection from Earth. Scientists have learned to use albedo in determining the size and shape of space objects that cannot be captured by a camera. The Air Force Phillips Laboratory in Maui, Hawaii uses albedo as one source to conduct measurements to characterize the orbital debris LEO environment. The U.S. Space Surveillance network primarily tracks deep space objects (those with orbital periods greater than 225 minutes) using optical sensors that detect reflected sunlight.  The observed brightness of a space object depends on many factors besides its size, such as its orientation, its surface composition and the viewing geometry.
    This experiment gives a friendly hands-on demonstration of determining and analyzing albedo and takes into account a space object in a mock revolving orientation.

    1. What is Orbital Debris? 

    2. Overview of Albedo Experiment

    3. Procedure for the Experiment

    4. Teacher Feedback to the Academy

    5. Discussion Forum

  • 2. Overview of Albedo Experiment

    The Albedo Experiment will allow students to collect data on albedo (reflected light) in real-time from models of items that might be found orbiting the earth in LEO (Low Earth Orbit) or beyond. The sections of this activity will guide you in learning about LEO debris, preparing equipment, the use of the Kepler Light Grapher, and the possible models that you might use to perform the experiment.  

    Albedo is the amount of light that is reflected from a surface. The image below is from "A Blog About the Universe" and illustrates how light from a light source reflects from a surface. In the Experiment noted below, students will use a Control Target to gather data on albedo and compare it to an Experimental Target as the affect of texture, color, etc. on albedo are considered.

    The image depicts sunlight hitting a surface and being reflected at a 90 degree angle from the surface.  If the surface is light is the albedo bounces back more intensely than if the image is darker in color.