You won't build the Hubble Space Telescope, but you can make your own inexpensive telescope.
Telescopes have been responsible for some of the most important discoveries in human history. From Galileo's discovery that the unchanging heavens were anything but, to the Hubble Space Telescope's discoveries of dark matter 400 years later, astronomical discoveries have changed human perception of the world. Although telescopes are powerful instruments, they need not be expensive. You can build a telescope like Galileo's from inexpensive parts. Kepler invented a slightly different telescope a few years later, and you can also build one like his.
Instructions
Building Galileo's Telescope
1. Galileo built his telescope in the early 1600s. It changed the world.
Glue the 980 mm focal length lens in one end of the 35-inch mailing tube. Three dabs of silicone RTV will do the job. If the lens is more curved on one side than the other, put the more curved side facing the outside of the tube.
2. Cut a 10-mm diameter hole in one of the mailing tube ends.
3. Center the negative focal length (diverging) lens on the hole in the mailing tube end and glue it in place with the RTV.
4. Slip fit or glue the end cap onto the end of the 5-inch cardboard tube. Again, if one side is more curved than the other, face the curved side outward.
5. Slide the smaller tube into the open end of the mailing tube. Look through the telescope and adjust the focus by moving the tube. The best focus should be close to when the small tube is almost entirely inside the larger tube.
Building Kepler's Telescope
6. Follow the first two steps of the procedure above.
7. Center the 50 mm focal length positive lens on the hole in the mailing tube end and glue it in place with the RTV.
8. Slip fit or glue the end cap from Step 2 onto the end of the 10-inch long cardboard tube. Again, if one side is more curved than the other, face the curved side outward.
9. Slide the smaller tube into the open end of the mailing tube. Look through the telescope and adjust the focus by moving the tube. The best focus should be with the small tube about halfway in the larger tube.
Tags: mailing tube, curved side, more curved, focal length, hole mailing, hole mailing tube, than other
