What's New?


Featured Tool:
Compress the 10 billion years history of the Universe into a year and find out when the interesting stuff happened with the Universe Timeline!



Saturn Ratings

  • Astronomy Classroom
  • Explore the Possibilities
  • Solar System Calculators
  • Solar System Viewers
  • Working With Orbits
  • Orbital Integrators
  • Extragalactic
  • Index of all Tools


  • Saturday's
    Astro Fact:
    Did you know that the Earth's magnetic field reverses itself periodically, so compasses that point North today will one day point to the South? More...
    visits to the Astronomy Workshop since January 1st, 2000. 

    Materials for Students and Instructors.

    Created by Dr. Douglas P. Hamilton and students at U. Maryland. We gratefully acknowledge support from NSF (1998-2003) and NASA (2003-2010). About Us