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How to Clean the Primary Mirror on a Telescope

Reflecting telescopes are a great upgrade from their refracting predecessors. With the ability to collect more light, reflecting telescopes are what the government and the amateur astronomer use. However, this tool still needs to be cleaned occasionally. The primary telescope mirror may be collecting too much dust, or it may have gotten a smudge on it. Either way, it may be time to wash it off. Although this is not a difficult task, it still must be done with great patience and care so as not to ruin your mirror.

Things You'll Need

Screwdriver
5 gallon plastic tub
Dish soap
Distilled water
Bath towel
Cotton balls (optional)

Instructions

- 1
  Add enough of the distilled water to the plastic tub to complete submerge the mirror, and place about 5 to 6 drops of dish soap into the water. Slosh around the water mix until it turns slightly bubbly.
- 2
  Remove the screws from the optical tube of the telescope. Be careful not to break the mirror when doing this.
- 3
  Submerge the mirror into the soapy mixture, being careful not to touch the mirror face itself. Make sure the mirror is completely submerged, and don't be afraid to add extra water if it is not.
- 4
  Slosh the water over the mirror, gently, for about 10 minutes. If your mirror looks clean, great. If it still has some stubborn dirt on it, use a cotton ball to remove the contaminants.
- 5
  Remove the mirror from the soapy water, and rinse it off by pouring a gallon of distilled water all over the face of the mirror.
- 6
  Air-dry the mirror on top of a towel. Trying to dry it off yourself can cause scratches or streaks, so refrain from using the towel to quick-dry the mirror.
- 7
  Replace the dry mirror into the optical tube and tighten the screws. After the mirror is correctly aligned, the telescope will be ready for star gazing once again!

Astronomy