Stellarium is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope. It is being used in planetarium projectors. Just set your coordinates and go.(from website).

Visit for more information and ideas.

Lesson Overview

This lesson uses the Stellarium software to give students of any age (you can modify it for your particular age group) an opportunity to view what is in essence a portable planetarium. You can do any type of activity that would be appropriate for a planetarium setting with Stellarium. This lesson is a simple lesson designed to illustrate the rotation of the Earth by observing the stars.

Historically, it was believed that the Earth was the center of the universe and that the stars revolved around us. Based on what can be observed from Earth that is not unrealistic.


  • This activity is appropriate for elementary through high school students.


  • The activity should take between 30 - 60 minutes depending on the amount of time you wish to give students for exploration. Their time with Stellarium is mainly to collect data. You will need additional time for students to explore what the data means and discuss it with their peers.


  • Computer lab with Stellarium software installed

  • A journal for writing down observations


  • Spend some time with the software before going to the lab. While students can explore on their own, it will save time if you give them some specific directions to get started
  • You might consider whether working individually will be better for your students, but small groups of 2 or 3 will probably work better as it is a collaborative activity.
  • At some point, encourage students to share information with another student or group.


  • Students will explore the rotation of the heavens from various locations on Earth
  • Students will make observations, share findings and extrapolate to make discoveries


  • Students will be able to explain how the rotation of the heavens varies based on ones location on the Earth
  • Students will describe how observation of the heavens can help one understand their location on the Earth
  • Students will be able to explain how observations of the heavens can be used to understand how the Earth rotates.
  • Students will understand that it is the Earth that is moving, not the stars and perhaps discover how Copernicus made his own similar discovery.


  • Begin with some discussion about the history of observation. Pay particular attention to early beliefs that the Earth was the center of the Universe. Prior discussion or research on Copernicus may be useful.
  • Take students to the lab and have the open the Stellarium program (taking them at least once to "play" prior to the work day may help them learn to use the program as well as "get it out of their system").
  • Instruct students to open the configuration panel and choose a location on the planet - perhaps begin with their home town.
  • Turning off atmosphere will help make the stars visible all the time. Click on the speed buttons to speed up the rotation to something close to 1 day every 10 seconds or so. This will allow students to observe the rotation at a speed that makes it obvious.
  • At this point students should now be documenting their observations
  • Encourage them to choose multiple locations and write down their observations.
  • Be sure all students choose a location near the north pole, one at the south pole, and one near the equator.
  • Encourage them to describe how the stars appear to move. See if they can picture themselves standing on a rotating planet even though it "appears" the stars are moving.
  • It may also be useful to have them pick a location and watch the movement of the planets for several weeks, months or even years (obviously by speeding up time).
  • After 30 - 60 minutes of observation, students return to class to share their findings, discuss what it means, and understand how they can use the information.


Lesson developed by Jim Hutchinson - Media Specialist at Windsor High School in Windsor, CO

Lessons/Stellarium (last edited 2008-08-06 16:19:30 by localhost)