A refracting telescope uses _______ to focus light.

• Lenses

• Mirrors

• Lasers

• Water

Reflecting telescopes use _______ to focus light.

• Lenses

• Flat mirrors

• Curved Mirrors

• A lens and lasers

Modern telescopes are reflecting because: (Choose all that apply)

• Lenses are difficult to manufacture

• Lenses are heavy and fragile

• lenses absorb light that passes through them

• Lenses require only 1 perfect surface

Modern telescopes don't use film to capture images, instead they use:

• CCDs

• USBs

• HDDs

• CD-ROMs

One of the issues created by the air surrounding us is:

• Interferometry

• Reflection

• Interference

• Atmospheric blurring

Which of these can solve the issue of atmospheric blurring? (choose all that apply)

• Active Optics

• Adaptive Optics

• Putting a telescope in space

• Putting a telescope underground

What type of telescope can work 24 hours a day and even be used in the rain?

• Refracting Telescope

• Radio Telescope

• Newtonian Telescope

• Solar Telescope

What types of telescopes have to be placed in space? (Choose all that apply)

• X-ray Telescopes

• Gamma ray Telescopes

• Infrared Telescopes

• Radio Telescopes

Why must Ultra-Violet observing be done in space?

• The ozone blocks most of the UV rays in the surface.
• It’s hard to know exactly where the ozone hole will be to find UV images
• It’s hard to use UV telescopes and radio telescopes together on the surface.
• It’s hard to use UV X-Ray telescopes and radio telescopes together on the surface

Why is the Hubble telescope located in space?

• So it can be closer to the stars it magnifies
• They have very large optical lenses
• So its images arent distorted by Earth's atmosphere 
• So it can be operated by astronauts