Astronomy Glossary of Terms

Astronomy Glossary of Terms

  ABCDEFGHIJK LMNOPQR STUVWXYZA Aberration – defects in images produced by a telescope (or optical system). They are caused by limitations in the design and manufacture of the optics. Find out...

Astronomy Glossary of Terms

  ABCDEFGHIJK LMNOPQR STUVWXYZA Aberration – defects in images produced by a telescope (or optical system). They are caused by limitations in the design and manufacture of the optics. Find out...

What are the different eyepiece sizes/diameters?

Astronomical eyepieces are described by the diameter of the base tube or barrel and come in several standard diameters. This is not to be confused with the focal length of...

What are the different eyepiece sizes/diameters?

Astronomical eyepieces are described by the diameter of the base tube or barrel and come in several standard diameters. This is not to be confused with the focal length of...

The Ultimate Guide to Celestron Optical Tubes

The Ultimate Guide to Celestron Optical Tubes

From refractors to reflectors to Cassegrains—there are so many telescope optical designs to choose from, each with its unique advantages and disadvantages. In this guide, our experts break down eac...

The Ultimate Guide to Celestron Optical Tubes

From refractors to reflectors to Cassegrains—there are so many telescope optical designs to choose from, each with its unique advantages and disadvantages. In this guide, our experts break down eac...

I need a shutter release cable for my Nexstar 4/5SE mount. Where can I f...

Unfortunately Celestron does not sell this cable separately from the scope. However, they are available online. Please reach out to any third-party dealer. Or you can make one. Here is...

I need a shutter release cable for my Nexstar 4/5SE mount. Where can I f...

Unfortunately Celestron does not sell this cable separately from the scope. However, they are available online. Please reach out to any third-party dealer. Or you can make one. Here is...

What's the difference between Variable Polarizing filter, the Neutral De...

Neutral Density Moon FilterThe 94105 Neutral Density Moon Filter is a filter that attaches to a 1.25” eyepiece that lowers the amount of light entering the eyepiece by 87%. In...

What's the difference between Variable Polarizing filter, the Neutral De...

Neutral Density Moon FilterThe 94105 Neutral Density Moon Filter is a filter that attaches to a 1.25” eyepiece that lowers the amount of light entering the eyepiece by 87%. In...

RASA 8 Questions and Answers

 Why can’t the Rowe-Ackermann Schmidt Astrograph (RASA) 8 be used visually?The optics produce an image at the front end of the telescope, not the back. Therefore, you cannot look through...

RASA 8 Questions and Answers

 Why can’t the Rowe-Ackermann Schmidt Astrograph (RASA) 8 be used visually?The optics produce an image at the front end of the telescope, not the back. Therefore, you cannot look through...