There are many star projectors on the market for purchase. These are typically round spheres or domes that are turned on in a dark room. Lit points are projected on the wall to mimic stars. Revolutions of the device can be set at differing speeds to track the movement of the stars. These can be expensive however, running at about $50 to $200.
Some star projectors come with more than just stars. For instance, the Star Theater 2 by Uncle Milton comes with films that display comets, so users can track comets' movements through the sky and viewers can watch guided tours of the stars. A compass is also included to allow you to view the night sky as it would appear on that exact night. Some projectors are more of a box shape, with small convex lenses to project stars, and come with books and CD-ROMs for study.
For the crafty individual who does not want to spend $100 or more on a store star projector, homemade projectors are fashioned from globes and cylinders. The Home Planetarium Association shows a cylinder with "star" points, or holes, that are drilled into the cylinder at exact points. An LED flashlight is shown through and the stars are projected.
As a second method, a globe can be cut in half and used to project stars. The Home Planetarium Association outlines the best size of drill marks to make, the coordinates to follow and the size of globe to be used. Instructions for these are on the technical side, and are meant for the most serious planetarium enthusiast.
A homemade dome can also be fashioned out of sheets draped on a steal frame. Sometimes the same method will be used with several white posters attached to a steal frame. These domes create a more realistic experience, similar to an institutional planetarium.
For the less technical-minded, or someone who just wants a faster and less expensive project to complete, home planetariums can be made out of an oatmeal container and a flashlight. The flashlight is secured in the oatmeal can by cutting a hole just big enough for the flashlight head in the lid of the can. On black paper, a constellation is drawn. The points where the stars would be have a hole punched in them. This is attached to the container with tape and the light shines through the holes, showing the constellation points.