Introduction: Students discover the properties of black holes based on their understanding of
gravity and velocity. They also analyze astronomical images from the Hubble
Space Telescope and Sloan Digital Sky Survey. Through an experiment, they
define escape velocity. Then they extend this idea to a black hole, which is an
object with an escape velocity equal to the speed of light. In the final activity,
students become astronomers in charge of a new database of super-massive
black holes. Their job is to evaluate new claims to decide if they are valid. They
design an evaluation rubric and apply their new understanding of black holes to
make their decisions. They also use real scientific data from Dr. Karl Gebhardt's
black hole database.McDonald Observator
