Chapter 6 quiz questions astronomy

Which causes the biggest problem in detecting infrared photons from an astronomical object with a ground-based telescope?

Water vapor

The light-gathering power of a 4-meter telescope is _______than that of a 2-meter telescope.

4 times larger

Put the telescopes in order of decreasing wavelength of the radiation that they observe. From the longest wavelengths to the shortest.

Green Bank, Spitzer, Galex, Fermi

You are shopping for telescopes online. You find two in your price range. One of these has an aperture of 20 cm, and one has an aperture of 30 cm. Which should you choose, and why?

The 30 cm, because the light-gathering power will be better

The largest astronomical refractor has an aperture of 1 m. Why it be impractical to build an even larger with, say, twice the aperture?

The degree of chromatic aberration increases as the focal length gets longer, and this would reduce image quality. The tube would have to be so long that housing and moving it would be extremely difficult, especially because it would be frontloaded with weight. A lens with a 2 m diameter would be very heavy and would deform under its own weight within a few years.

Apply the correct definitions a.) Chromatic aberration b.) Aperture c.) Interferometer d.) Focal length e.) Resolution f.) Diffraction

a.) Rainbow-making effect b.) Diameter c.) Several telescopes connected to act as one d.) Distance from lens to focal plane e.) Ability to distinguish objects that appear close together in the sky f.) Smearing effect due to sharp edge

Which of the following can be observed from Earth's surface? select all that apply a.) radio waves b.) UV light c.) gamma radiation d.) X-ray light e.) visible light

a.) radio waves and e.) visible light

The angular resolution of a ground-based telescope is usually determined by:

atmospheric seeing

Robotic landers are more common than simple-return spacecraft because:

carrying enough fuel to get back to Earth makes sample return expensive

Which of the following Solar System objects has yet to be observed by flyby spacecraft? a.) Uranus b.) Venus c.) Neptune d.) Pluto

d.) Pluto

The Kepler Mission telescope observes primarily in visible light. This telescope is located in space because

it is above atmospheric distortion

Suppose that you are handed a telescope. The tube is roughly as long as your arm, gut is difficult to hold because you can barely get your arms around it. This telescope is most likely a

reflector

The advantage of an interferometer is that:

the resolution is dramatically increased

Spacecraft are the most effective way to study planets in our Solar System because:

they can collect more information than is available just from images.

The major advantage CCDs have over other imaging techniques is that they:

yield output in digital format, have a higher quantum efficiency, have a linear response to light, and operate at visible and near-infrared wavelengths.