Classroom Discussion Activity

Beyond Our Solar System:Searching for Extrasolar Planets

Astrophysicists are discovering new extrasolar planets—those outside our Solar System—almost daily. NASA’s Spitzer Space Telescope (originally called SIRTF, or the Space Infrared Telescope Facility) and AMNH’s Lyot Project Coronograph are two of the many technologies uncovering the attributes and evolution of these faraway worlds. The techniques employed by these instruments may one day help answer one of astronomy’s reigning mysteries: do any extrasolar planets host life?

Scientific Process 

This feature story is an illustration of the process of science because it shows technologies and techniques scientists use to collect evidence of planets outside our solar system (read more about The Scientific Process).


Establish Prior Knowledge
Review the electromagnetic spectrum with your students. Point out that the spectrum is the complete array of electromagnetic radiation, or light, and that visible light is only part of the spectrum. Ask students why it is necessary for telescopes that are used to gather data about the Universe to detect other wavelengths of light. Tell students that in the video they are about to see, scientists use infrared light to detect planets outside our solar system.

Have students watch the video. Tell students that in the several years since the video was produced, many discoveries have been made about extrasolar planets using the technologies discussed in the video. Divide students into groups and assign each group a Snapshot to investigate.

  • Astro Bulletin: First Look at Faraway Worlds (November 24, 2008)
  • Astro Bulletin: First Molecules Detected on Extrasolar Planets (March 12, 2007)
  • Astro Bulletin: Found: Least Dense Extrasolar Planet (September 25, 2006)
  • Astro Bulletin: Planets May Host Planets (June 12, 2006)
  • Astro Bulletin: Tiny, Rocky Extrasolar Planet Detetcted (February 6, 2006)
  • Astro Bulletin: Can Brown Dwarfs Build Planets? (October 31, 2005)
  • Astro Bulletin: First Light Detected from Extrasolar Planet (March 28, 2005)

Have students present the key findings from the snapshots they watched. Have students discuss what they think was surprising and/or exciting about each discovery.