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Final Exam Review
Questions from other exams for the final exam
120
Astronomy
Undergraduate 1
05/03/2010

Additional Astronomy Flashcards

 


 

Cards

Term
1.Our latitude can be found by measuring the
Definition
altitude of the North Celestial Pole (near Polaris)
Term
2. The local celestial meridian passes through all of the following points on the celestial sphere except
Definition
the east point on the horizon
Term
3. We call the point directly overhead the
Definition
zenith
Term
4. The meter is used to measure
Definition
length
Term
5. Which celestial body appears to cross the local celestial meridian about once/day due to diurnal motion
Definition
a star, a planet, sun, moon
Term
6. Where on earth would the celestial equator pass through the zenith of an observer
Definition
geographic equator
Term
7. What name do we give to the apparent path of the sun in the sky
Definition
Ecliptic
Term
8. The astronomical unit AU is equal to
Definition
the distance between the earth and the sun
Term
9. The apparent paths of the stars in the night sky are easily pictured when the stars are imagined to live on an imaginary object called the
Definition
celestial sphere
Term
10. The point on the celestial sphere directly beneath the observer is know as the
Definition
nadir
Term
11. A time exposure of the North Sky shows a circular pattern. The center of the circle is
Definition
exactly at the North Celestial pole
Term
12. Where on the earth do objects in the sky appear to move in circular paths parallel to the horizon
Definition
North Geographic pole
Term
13. The sun appears to move through the sky
Definition
about 1 degree eastward/day
Term
14. The circle in the sky lies halfway between (or 90˚ from) the celestial poles and passes through the East and West points on the horizon. It is called the
Definition
celestial equator
Term
15. The line in the sky which runs East to West and divides the sky into Northern and Southern hemispheres is called the
Definition
celestial equator
Term
16. Much of the difficulty in studying celestial bodies arises from the large
Definition
distances between them
Term
17. The number 3.3X10 to the -3 power is equal to
Definition
0.0033
Term
18. The plane of the earth’s equator is inclined to the plane of its orbit at an angle of
Definition
23.5˚
Term
19. A first magnitude star is ___ times brighter than a 2nd magnitude star
Definition
2.5
Term
20. At what location on the earth would the South Celestial pole be located on your horizon
Definition
equator
Term
21. 30 arc minutes is about
Definition
0.5˚
Term
22. As seen by an observer at the earth’s equator, where does the North Celestial pole appear in the sky
Definition
at the North point on the horizon
Term
23. A star of the 6th magnitude differs in brightness from one of the 1st magnitude in that it is
Definition
100 X brighter
Term
24. At the north pole of the earth the horizon and the _____ _____ appear to coincide
Definition
celestial equator
Term
25. Aristarchus of Samos was famous for
Definition
calculating the relative sizes and distances of the sun and moon
Term
26. Suppose you are at the earth’s south pole, where would the North Celestial pole be
Definition
be at your nadir
Term
27. Stars which are said to be circumpolar
Definition
never go below or rise above one’s horizon
Term
28. The universe contains
Definition
hundreds of billions of galaxies
Term
29. During the night, most stars appear to
Definition
move across the sky from East to West
Term
30. The solar system is located
Definition
near the outer portion of the galaxy
Term
31. The name “planet” was used by ancient astronomers to mean
Definition
any object which appeared to move relative to the sun
Term
32. The ancient Greeks believed the earth was stationary because
Definition
dropped objects fall straight down, no stellar parallax was seen, no strong winds from East to West
Term
33. Where on the earth’s surface is each star above the horizon ½ the time
Definition
at the equator
Term
34. The person who is remembered for measuring the circumference of the earth was
Definition
Eratosthenes
Term
35. The apparent annual motion of the sun is
Definition
from East to West along the ecliptic
Term
36. The rotation axis of the earth reaches the celestial sphere and defines 2 points called the
Definition
North and South Celestial poles
Term
37. The distance between which is the largest is the
Definition
parsec
Term
38. Which abbreviation below represents 1,000 m
Definition
km
Term
39. For an observer located at earth’s North Pole the Celestial Equator
Definition
is located on the observer’s horizon
Term
40. Polaris is called the pole star because it lies very close to the
Definition
North Celestial Pole
Term
1. The truth about the telescope
Definition
Galieo didn’t invent it, but he was the first to use it
Term
2. One theory that places the earth at the center of the solar system with the sun and the planets orbiting about it is the
Definition
Ptolemaic Model
Term
3. The distance between crests of a wave is called the
Definition
wavelength of a wave
Term
4. Astronauts in orbit are
Definition
apparently weightless because they are in free fall
Term
5. The gravitational attraction of the sun on a planet is _____ when the planet is at larger distances from the sun
Definition
smaller
Term
6. “For every action there is an equal and opposite reaction” is a statement of
Definition
Newton’s 3rd Low of Motion
Term
7. The ecliptic and celestial equator intersect at 2 points called the
Definition
equinoxes
Term
8. The earth is closest to the sun
Definition
on about January 3rd
Term
9. Newton’s 2nd law said
Definition
“force is proportional to mass multiplied by acceleration”
Term
10. At about what time of night would you expect to see a full moon highest in the sky
Definition
12 midnight
Term
11. The theory of universal gravitation was developed by
Definition
Newton
Term
12. Of the colors of visible light listed below, which has the longest wavelength
Definition
a. Blue RED green orange yellow
Term
13. Which of the following lows describes the shapes of planetary orbits
Definition
Kepler’s 1st Law
Term
14. Summer occurs for an observer on the earth because
Definition
days are longer than nights
Term
15. When we experience spring in the North Hemisphere it is ____ in the South Hemisphere
Definition
fall
Term
16. The retrograde motion of Mars can best be explained as
Definition
the earth overtaking and passing Mars
Term
17. The plane of the earth’s equators inclined to the plane of it’s orbit is at an angle of
Definition
23 ½ ˚
Term
18. The observation that Mercury and Mars never get high in the night sky was explained by
Definition
both the geocentric and heliocentric models
Term
19. The North Star will not always lie close to the North Celestial Pole and be our North Star because of the
Definition
precession of the earth
Term
20. Precession is caused by
Definition
the gravitational attraction of the sun, rotation of the earth, the oblate shape of the earth
Term
21. Temperature is a measure of the average ______ __ ______ of the particles of a substance
Definition
energy of motion
Term
22. If the force of the sun’s gravity were suddenly turned off
Definition
the earth would continue to move, but in a straight line
Term
23. The seasons are caused by the
Definition
23 ½ ˚ tilt of the earth’s axis
Term
24. Kepler’s 3rd law states that the square of the orbital period of a planet is proportional to
Definition
it’s orbital semi-major axis cubed
Term
25. The arrangement of light by colors is called
Definition
the spectrum
Term
26. Where in their orbits do planets move the greatest speed about the sun
Definition
when they are closest to the sun
Term
27. If you see the moon rise at noon, it’s phase must be
Definition
1st quarter
Term
28. Newton’s 3rd law: the strength of the gravitational force of the earth pulling on the moon is
Definition
equal to that of the moon pulling on the earth
Term
29. The apparent annual motion of the sun is
Definition
from West to East along the ecliptic
Term
30. It is summer in the Northern Hemisphere when
Definition
the sun is furthest North of the Celestial Equator
Term
31. The band of constellations through which the planets, sun and moon move is called
Definition
the zodiac
Term
32. If you were spending July in Australia, you’d be experiencing
Definition
winter
Term
33. The change in the orientation of earth’s axis of rotation has a period of about 26,000 years is called
Definition
precession
Term
34. With one of the 1st telescopes Galileo discovered
Definition
the mountains of the moon, the 4 brightest moons of Jupiter, the Milky Way is made up of individual stars, sunspots
Term
35. Ptolemy could not explain _______ _______ __ __ ________ without epicycles and deferents
Definition
retrograde motion of the planets
Term
36. A 3rd quarter moon will set at
Definition
noon
Term
37. The sideral day and the solar day are not the same length because the earth is
Definition
revolving
Term
38. According to the Special Theory of Relativity the _____ __ _____ are the same for all observers
Definition
laws of nature (physics)
Term
39. We remember Tycho Brahe as
Definition
the best observational astronomer of his time
Term
40. The moon at 1st quarter looks like a ____ circle
Definition
half
Term
1. Periodic decreases in the total amount of light received from a star may indicate that our single star is an
Definition
eclipsing binary
Term
2. What is the function of the objective of an optical telescope designed for visual use
Definition
to gather light and form an image
Term
3. In a reflecting telescope, the focus behind the hole in the main mirror is called the
Definition
Cassegrain focus
Term
4. If a star has a parallax of ¼ second of an arc, then its distance is
Definition
4 parsecs
Term
5. The largest telescope used for observation in the visible light region of the spectrum
Definition
are reflecting telescopes
Term
6. The greatest proportion of the mass of the atom is found
Definition
in the nucleus
Term
7. The visible light spectrum of Hydrogen atom is made up of laws which make up the ______ series of Hydrogen
Definition
Balmer
Term
8. On the H-R diagram, where would you find the sun
Definition
on the main sequence
Term
9. Compared to the 100” reflector of Mt Wilson, how much light can be gathered by the 200” reflector on Mt Palomar
Definition
4x as much
Term
10. Which of the following is produced by a very hot solid
Definition
a continuous spectrum
Term
11. The frequency at which a star emits the most light depends upon the star’s
Definition
temperature
Term
12. A star which has an annual parallax of 1 arc second is at a distance form the sun of
Definition
1 parsec
Term
13. Most stars on the H-R diagram are
Definition
main sequence stars
Term
14. Why do stars appear to be of different colors
Definition
because of their surface temp.
Term
15. The absolute magnitude of a star is a measure of it’s
Definition
brightness as seen from a distance of 10 parsecs
Term
16. Refracting telescopes are telescopes which
Definition
use lenses to form an image
Term
17. When an electron jumps spontaneously from a higher state to it’s lowest orbit
Definition
a photon is emitted
Term
18. An object is observed to have a spectrum consisting only of emission lines. Therefore, it is
Definition
a hot, low density gas
Term
19. The H-R diagram is a graph of
Definition
absolute magnitude vs. spectral type (temp.)
Term
20. The higher the frequency of electromagnetic radiation
Definition
the shorter its wavelengh
Term
21. Stars in the main sequence that have a small mass are
Definition
dim and cool
Term
22. The resolution of a telescope (the ability to see fine details) is dependent on
Definition
the diameter of the objective (primary lens or mirror)
Term
23. An angstrom is
Definition
much smaller than an inch
Term
24. The distances to the nearer stars may be measured by observing the
Definition
parallax
Term
25. The radial velocity of a star is
Definition
its speed toward or away from us
Term
26. If the light from a star produces 2 sets of absorption lines with different Doppler shifts, the star is called
Definition
spectroscopic binary
Term
27. Of the following types of electromagnetic radiation, which has the shortest wavelength
Definition
a. Red light, radio, infared, ultraviolet, X-Ray
Term
28. In order of increasing wavelength
Definition
gamma ray, x-ray, ultraviolet, infared, radio
Term
29. For a star moving away from us at 100 km/sec, which shift would spectral lines have and how would the shift depend on the star’s distance
Definition
shifted to the red, independent of the distance
Term
30. The major spectral classes in order from hottest to coolest are
Definition
O B A F G K M
Term
31. In the H-R diagram the supergiants are
Definition
located across the top
Term
32. The difference in apparent position of an object as seen from 2 different locations
Definition
parallax
Term
33. The type of binary which are actually to be seen as 2 stars when viewed through a telescope is
Definition
visual binary
Term
34. If one had a Newtonian reflecting telescope, where would one look to find the eyepiece of it
Definition
near the top of the telescope to one side
Term
35. The change in the observed wavelength from a wave source due to its motion toward or away from us is called
Definition
the Doppler Effect
Term
36. How does the astronomer obtain a star’s radial velocity
Definition
from the Doppler shift in the star’s spectrum
Term
37. Stefan-Boltzman law states that
Definition
the total energy emitted by an object (star) equals the 4th power of its temperature
Term
38. The masses of celestial objects are usually found from the
Definition
gravitational effects on outer objects
Term
39. What characteristics of a telescope can we change when we change the eyepiece
Definition
magnification
Term
40. Which of the following is not formed electromagnetic radiation
Definition
a. X-rays, beta rays, gamma rays, ultraviolet light, radiant heat
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