Cypress College ASTR 116 Homework
Astronomy 116, Homework CHAPTER 3 (A) Telescopes. Due:
Print Last, First Name and date on the small Scantron in INK. Print
your last name in BIG BLOCK letters on the back of the Scantron.
Use a No. 2 pencil to fill out Scantron. Read the chapter.
Look at the videos and simulations in the CD-ROM. Answer all True/False and
Fill in the Blank questions. Then answer the following questions and
turn in your Scantron only. Choose the best answer.
1. What is the resolving power of a telescope?
- a) its ability to distinguish two adjacent objects in the sky
- b) its ability to collect a large amount of light
- c) the amount of magnification
- d) its ability to separate light into various wavelengths
2. What is the primary advantage of CCDs over the photographic plate?
- a) They record up to 75 percent of the light instead of only 5 percent.
- b) Images do not have to be developed.
- c) They can be used to record large sections of the sky.
- d) Their images will never fade.
3. Which of the following is a problem inherent to all large radio telescopes?
- a) They are all badly affected by atmospheric seeing.
- b) The slightest bit of wind shakes them about, preventing observations.
- c) They have poor angular resolution.
- d) They have difficulty detecting weak signals.
- e) None of the above.
4. What is "seeing"?
- a) It is a measure of the quality of a telescope's optical system.
- b) It is a measure of the image quality due to the stability of
the air.
- c) It is a standard by which astronomers compare and contrast their
own eyesight with that of their colleagues.
- d) It is a difference related strictly to cold- and warm-weather
observing.
5. Why are CCDs, or charge-coupled devices, so useful to astronomical
research?
- a) Images made by CCDs are easily read and manipulated by computer
programs.
- b) CCDs provide a precise measurement of changing light intensity
across a given area.
- c) CCDs detect light more efficiently than photographic plates.
- d) all of the above
- e) none of the above
6. Radio dishes must be large in order to:
- a) Detect the small amount of radio energy reaching Earth.
- b) Attract funding.
- c) Achieve angular resolution better than optical telescopes.
- d) To capture the very large wavelengths of radio waves.
7. Which of the following has greatly improved the angular resolution
of radio maps?
- a) Interferometry.
- b) Schmidt telescope design.
- c) Spectroscopy.
- d) Charge-coupled device.
8. What is one advantage of large telescopes over small ones?
- a) Large telescopes have a wider field of view.
- b) Large telescopes collect more light than small ones.
- c) Large telescopes are easier to mount.
- d) Large telescopes are heavier and therefore more stable and accurate
in pointing.
9. A reflecting telescope has a focus which results from a single secondary
mirror, and which forms through a hole in the primary mirror. This
is called the
- a) prime focus.
- b) Newtonian focus.
- c) Cassegrain focus.
- d) Coude focus.
10. Chromatic Aberration is a defect encountered in:
- a) radio telescopes
- b) refracting telescopes
- c) reflecting optical telescopes
11. A 20. cm telescope collects how many times the light collected by
a 5 cm telescope?
12. The Arecibo Observatory is:
- a) an X-ray observatory
- b) a radio observatory
- c) a large optical observatory
- d) an adaptive optics observatory