Telescopes and the EM Spectrum and the Stars

Astronomers often scan the sky using devices called radio telescopes. What can you conclude about these devices?

• a. They send radio broadcasts out to distant stars and planets. b. c. d.

• They pick up the radio waves emitted by stars.

• They are less powerful than optical telescopes.

• They can detect ultraviolet radiation.

Tim mentions that infrared radiation can be used to take special pictures called thermographs. "Graph" means "image." What can you infer about the prefix "thermo?"

• It means "light"

• It means "energy"

• It means "heat"

• It means "radio"

Scientists who study the universe beyond the Earth.

• cartographers

• cosmologists

• astrophysicists

• astronomers

Energy that is transmitted through space as a wave.

• radio waves

• visible light

• infrared light

• all forms of electromagnetic radiation

Gamma rays-X Rays-Ultraviolet-Visible-Infrared-Microwave-Radio

• EM radiation

• EM spectrum - long to short wavelength

• EM spectrum - short to long wavelength

The hottest objects studied in our galaxy (and others) are best studies with the ___ and ___ they emit.

• X-Rays, Gamma Rays

• Microwaves, radio Waves

• Ultraviolet light, Infrared light

The earliest telescopes, which used lenses to bend light, are called _____.

• optical telescopes

• reflecting telescopes

• refracting telescopes

• radio telescopes

Newton built a different kind of telescope, that used mirrors to collect light. These are called _____.

• optical telescopes

• reflecting telescopes

• refracting telescopes

• radio telescopes

Large telescopes that are built to collect long wavelengths of EM radiation - are called:

• Schmidt-cassegrain telescopes

• Newtonian-Galilean telescopes

• Radio telescopes

• Catadioptric telescopes

Telescopes are often placed in space because _____.

• Pollution interferes with our view of space.

• Some wavelengths, like X-rays and gamma rays do not penetrate our atmosphere.

• They are easier to operate in space.

• Thy are cheaper to operate in space.