Weymouth Astronomy

Getting Started - Part 2

Cooling the telescope

If your telescope is stored inside the house (when not in use) you will need to allow the scope a period of cooling down time (approx. 20 minutes) when you position it outside. Itís important that your mirror be at the same temperature as the evening sky. If itís not, youíll have difficulty focusing the image because the mirror will be minutely flexed due to thermal differences. If the mirror is colder than the ambient air temperature, you may get dewing on the mirror like steam on the bathroom mirror after a shower. Either one of these will result in bad images through the eyepiece.

While your scope is adjusting to outside temperatures, this is an ideal time to allow your eyes to adjust to the darkness. While white lights (ie torches) are a no no!! red light will allow you to keep your night vision and enable you to see what you are doing.

After the telescope has 'cooled down' and your eyes have adjusted to the dark, you are now ready to start observing the skies. A good place to start with is The Moon.