Why Do Reflecting Telescopes Usually Have a Secondary Mirror in Addition

question 38

Multiple Choice

Why do reflecting telescopes usually have a secondary mirror in addition to a primary mirror?

• A) To increase the light gathering power
• B) To make the telescope shorter
• C) To increase the focal length
• D) To combat chromatic aberration

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Definitions:

Atlanto-axial

Pertaining to the joint formed between the atlas (first cervical vertebra) and the axis (second cervical vertebra) which enables head rotation.

Acetabular Labrum

A ring of cartilage surrounding the socket of the hip joint that helps to improve the stability of the joint.

Acetabulum

The socket in the pelvic bone that receives the head of the femur, forming the hip joint.

Articular Cartilage

Smooth, white tissue that covers the ends of bones where they come together to form joints, reducing friction during movement.