Astr 104, Spring 2008 – Quiz 2

1. Why do stars twinkle?
a. Because they are burning spheres of hot gas.
b. Because of their slow motion across the sky.
c. Because of the scattering of starlight caused by Earth's atmosphere.
d. Because their great distance weakens the light we get from them.

2. What is a reflecting telescope?
a. One that focuses the incoming light with a mirror rather a lens.
b. One in which light is reflected sideways after going through the primary lens.
c. One that gives inverted images of the astronomical objects seen through it.
d. One that produces negative images (dark stars on light backgrounds).

3. What does the angular resolution tell you about a telescope?
a. Its ability to produce bright images of faint objects.
b. The magnification of the images it produces.
c. Its ability to detect fine detail and produce sharp images.
d. The number of spectral lines one can see with it.

4. What is the angle at which a star is located above or below the celestial equator called?
a. Azimuth.
b. Declination.
c. Altitude.
d. Zenith.

5. What is the main reason the Hubble Space Telescope gives better images than most other telescopes?