Astronomy Test #1 (Ch. 0,1,2,and 3)

Chapter 3: Question 31
What problem do refractor telescopes have that reflectors don't?
A. bad seeing
B. chromatic aberration
C. atmospheric blurring
D. diffraction limited resolution
E. light loss from secondary elements

Chapter 3: Question 30
Which of the following is NOT a reason to use a reflecting telescope rather than a refractor?
A. Lenses are harder to focus than mirrors.
B. Lenses are subject to chromatic aberration.
C. Heavy lenses, which can only be supported at their edges, tend to deform under their own weight. 
D. A lens must have two precision surfaces; a mirror needs only one.
E. Lenses absorb light, while mirrors do not.

Chapter 3: Question 11
The light-gathering ability of a telescope is most dependent on the diameter of its primary objective. True or False?
True False

Chapter 3: Question 13
A telescope with an 8-inch mirror will collect twice as much light as one with a 4-inch mirror.
True or False?
True False

Chapter 3: Question 14
The 400" Keck reflector can see objects 100 times fainter than the 40" Yerkes lens. True or False?
True False

Chapter 3: Question 15
Radio telescopes have poorer angular resolution than optical telescopes because radio waves have a much longer wavelength than optical waves. True or False?
True False

Chapter 3: Question 39
What is the resolution of a telescope?
A. its ability to make distant objects appear much closer to us
B. its ability to distinguish two adjacent objects close together in the sky
C. its ability to see very faint objects its ability to separate light into its component colors for analysis
D. its ability to focus more than just visible light for imaging

Chapter 3: Question 42
Green light has a shorter wavelength than orange light. In a 5 inch telescope, green light will...
A. reduce the effects of atmospheric turbulence.
B. come to the same exact focus as orange light.
C. provide better angular resolution than orange light.
D. provide worse angular resolution than orange light.
E. allow dimmer stars to be observed.

Chapter 3: Question 18
The opacity of the atmosphere is partially corrected via adaptive optics. True or False?
True False

Chapter 3: Question 43
What problem does adaptive optics correct?
A. defects in the optics of the telescope, such as the original Hubble mirror
B. the opacity of the Earth's atmosphere to some wavelengths of light
C. the light pollution of urban areas
D. chromatic aberration due to use of only a single lens objective
E. turbulence in the Earth's atmosphere that creates twinkling

Reflecting Telescopes characterisitics and examples:

Refracting Telescopes characteristics and examples:

Chapter 3: Question 20
Optical telescopes are usually used only at night, but radio telescopes can be used day or night. True or False?
True False

Chapter 3: Question 21
The Earth's atmosphere is the major factor limiting the use of ground-based radio telescopes. True or False?
True False

Chapter 3: Question 22
Optical interferometry is more in use than radio interferometry. True or False?
True False

Chapter 3: Question 44
What is true of radio telescopes?
A. They are most sensitive to the opacity of the ozone layer.
B. They have better angular resolution than a reflector.
C. They are the smallest, most compact telescopes.
D. They have poorer angular resolution than a refractor of the same size.
E. They can only be used above the atmosphere.

Chapter 3: Question 46
In astronomy, an interferometer can be used to...
A. speed up the processing of CCD images.
B. increase the sensitivity of infrared telescopes to longer wavelengths.
C. improve the angular resolution of radio telescopes.
D. decrease the effects of light pollution in getting darker sky backgrounds.
E. yield better seeing conditions with optical telescopes.

Chapter 3: Question 28
Galaxies look the same whether viewed in visible or X-ray wavelengths. True or False?
True False

Chapter 3: Question 27
The Compton GRO was the first telescope used for our exploration of high-energy astronomy. True or False?
True False

Chapter 3: Question 26
The mirrors for X-ray telescopes are the same shape as those of optical reflectors. True or False?
True False

Chapter 3: Question 25
Due to our ozone layer, ultraviolet astronomy must be done from space. True or False?
True False

Chapter 3: Question 24
Like radio and optical astronomy, infrared astronomy is easily done with ground-based telescopes. True or False?
True False

Chapter 3: Prelecture Question 14
Which of the following regions of the elctromagnetic spectrum is useful for studying distant galaxies?
A. Radio waves
B. Visible light
C. Infrared light
D. Ultraviolet light
E. All of the above

Chapter 3: Question 50
Which of the following is currently supplying high resolution X-ray images from space?
A. ROSAT
B. Einstein
C. Chandra
D. HEAO-2
E. COBE

Conceptual Self-Test 3.02
The term seeing is used to describe how faint an object can be detected by a telescope. True or False?
True False

Conceptual Self-Test 3.03
One of the primary advantages of CCDs over photographic plates is the former's high efficiency in detecting light. True or False?
True False

Conceptual Self-Test 3.04
Radio telescopes are large in part to improve their angular resolution, which is poor because of the long wavelengths at which they are used to observe the skies. True or False?
True False

Conceptual Self-Test 3.05
Infared astronomy can only be done from space. True or False?
True False

Conceptual Self-Test 3.06
Gamma-ray telescopes employ the same basic design that optical instruments use. True or False?
True False

Conceptual Self-Test 3.07
Because gamma rays have very short wavelengths, gamma-ray telescopes can achieve extremely high angular resolution. True or False?
True False

Conceptual Self-Test 3.08
The main reason that most professional research telescopes are reflectors is that...
A. mirrors produce sharper images than lenses do.
B. their images are inverted.
C. large mirrors are easier to build than large lenses.
D. they do not suffer from the effects of seeing.

Conceptual Self-Test 3.10
The primary reason professional observatories are built on the highest mountaintops is to...
A. improve chromatic aberration.
B. reduce atmospheric blurring.
C. be above the rain clouds.
D. get away from city lights.

Conceptual Self-Test 3.11
When multiple radio telescopes are used for interferometry, resolving power is most improved by...
A. increasing the number of telescopes in a given area.
B. the distance between telescopes.
C. the electrical power supplied to each telescope.
D. the diameter of each telescope.

Conceptual Self-Test 3.12
The Spitzer Space Telescope (SST) is stationed far from Earth because...
A. Earth is a heat source and the telescope must be kept very cool.
B. this increases the telescope's field of view.
C. the telescope is sensitive to electromagnetic interference from terrestrial radio stations
D. doing so avoids the obscuring effects of Earth's atmosphere.

Conceptual Self-Test 3.13
The best way to study young stars hidden behind interstellar dust clouds would be to use...
A. blue light.
B. ultraviolet light.
C. infrared light.
D. X-rays.

Conceptual Self-Test 3.14 VIS
Resolution is sharpest when the ratio of wavelengths to telescope size is...
A. Small
B. large
C. close to 1
D. none of these

Conceptual Self-Test 3.15 VIS
The best frequency wave in which to study the hot (million-kelvin) gas found among the galaxies in the Virgo cluster would be...
A. in gamma rays.
B. in the infrared rays.
C. at radio frequencies.
D. in X rays.

Chapter 1: Question 16
In Ptolemy's geocentric model, retrograde motion occurs when the planet is closest to us, on the inside portion of...
A. epicycle.
B. equant.
C. deferent.
D. ellipse.
E. ecliptic.

Chapter 1: Question 14
In Ptolemy's geocentric model, the planet's motion along its deferent is all that is needed to understand retrograde motion. True or False?
True False

Chapter 1: Question 22
Which of these was NOT seen telescopically by Galileo?
A. stellar parallax
B. craters and mare on the Moon
C. Four moons around Jupiter
D. sunspots
E. Venus' phase cycle

Chapter 1: Question 12
Galileo's observations of the entire phase cycle of Venus proved that Ptolemy's epicycles could not be correct in keeping Venus between us and the Sun. True or False?
True False

Vocabulary in Context: Kepler's Planetary Orbits
1. Earth is located at one __ of the Moon's orbit.
2. According to Kepler's second law, Jupiter will be traveling most slowly around the Sun when at __.
3. Earth orbits in the shape of a/an __ around the Sun.
4. The mathematical form of Kepler's third law measures the period in years and the __ in astronomical units (AU).
5. According to Kepler's second law, Pluto will be traveling fastest around the Sun when at __.
6. The extent to which Mars' orbit differs from a perfect circle is called its __.

Ranking Task: Kepler's Third Law of Planetary Motion
1. Planets move fastest when they are at the __ (right side).
2. Planets move slowest when they are at the __ (left side).
3. Planetary Orbits go __.
4. Does mass effect orbital periods?
5. Kepler's Third Law formula is __.

Ranking Task: Kepler's Second Law
1. Kepler's second law states: an imaginary line connecting the Sun to any planet sweeps out __of the ellipse in __.
2. When a planet is ___ to the Sun it moves ___ than when ___ away.
3. When an object is __ to the Sun then, it covers ___ than when it was ___.

Chapter 1: Question 8
Kepler found the orbits of planets are ellipses, not circles. True or False?
True False

Chapter 1: Question 25
Tycho Brahe's contribution to Kepler's Laws of Planetary Motion were...
A. his observations of Jupiter's moons.
B. the correct explanation of lunar phases.
C. his detailed and accurate observations of the planets' positions.
D. a mathematical explanation of epicycles.
E. a precise lunar calendar.

Chapter 1: Question 3
According to Newton's Second Law, if you double the force acting on a body, the acceleration will double. True or False?
True False