As astronomers have discovered more planets outside the solar system, they have come to realize that resonances play key roles in shaping the architectures of many multiple-planet systems. "Resonance" refers to a broad class of relationships in which one object perturbs another periodically.
Click on the still images below to view simulations of various planetary resonances in action. Sky & Telescope thanks the researchers for providing these animations. Click on the researchers' names to learn about their work.
This Web page is a supplement to the article "Planetary Harmony" by Robert Naeye (Sky & Telescope: January 2005, page 44). After February 1, 2005, the article will be available for download as a PDF file from the S&T Magazine Archive.