1. Which is not a constellation of the zodiac?
c) Ursa Major (the Greater Bear)
2. Which is an ancient constellation?
a) Canis Minor (the Smaller Dog) (All the others are of modern
devices)
3. Most proper star names are
b) Arabic
4. The "modern constellations" were invented
b) between about 1600 and 1800
5. The brightest star within a constellation is usually called
a) Alpha
6. The distance between the Earth and Sun defines the
d) Astronomical Unit
7. How far is the Earth from the Sun?
d) 93 million miles (or 150 million km)
8. Who was the first to see the phases of Venus and the moons of Jupiter?
a) Galileo
9. Planets move slowest in orbit when they are at
b) aphelion (farthest from the Sun) (Kepler's 2nd law)
10. Orbital paths can be
e) any of the conic sections (Kepler's first generalized law)
11. Spacecraft orbiting the Earth
e) are trying to fall back to Earth
12. Planetary orbits are affected by
e) the gravitational pulls of the planets on each other and on the
Sun
13. What must we know to derive the mass of the Sun?
e) both the period and semi-major axis of any planet around the Sun
(Kepler's third law)
14. If you could halve the radius of the Earth while keeping its mass
constant, you would weigh
b) 4 times what you do now
15. A newly discovered asteroid has a semi-major axis of 4 AU. What is its
orbital period in years?
d) 8 (P**2 is proportional to a**3)
16. If you boost an Earth-orbiting satellite into a higher orbit, its
period
a) increases
17. Which force holds the electrons to the atomic nucleus?
d) electromagnetic
18. Protons and neutrons are tied together in atomic nuclei by
a) the strong force
19. The photons of which kind of radiation below carry the most energy?
b) X rays
20. Which particles have nearly identical masses?
b) proton and neutron
21. The kind of atom, or element, is determined by the number of nuclear
a) protons
22. What makes an element or isotope radioactive?
e) too few or too many neutrons
23. A photon with a wavelength of 3,000 ¸ carries how many times more energy
than one at 30,000 ¸?
d) 10 (The energy of a photon is directly proportional to its
frequency)
24. Neutral 14N (nitrogen) has seven each of electrons, protons, and neutrons.
Neutral 15N has how many neutrons?
c) 8
25. A blackbody has its maximum radiation at 10,000 ¸ngstroms. If you were to
halve the temperature, the new point of maximum radiation would lie at
d) 20,000 ¸ (Wien law)
26. Which color star is the hottest?
a) blue (Basically, the Wien law again.)
27. If you triple the temperature of a spherical blackbody (and hold the
radius constant), its luminosity goes up by a factor of
e) 81 (Stefan-Boltzmann law)
28. If a star is moving away from the observer, the wavelength of the
hydrogen-beta absorption line
b) is shifted to longer wavelengths (Doppler effect)
29. How many times brighter would a star look through a 30 inch telescope than
it would through a 10 inch telescope?
b) 9 (Light gathering power goes as aperture squared)
30. The purpose of a radio interferometer is to
e) give very high angular resolution (detail)
31. The heat from the corona of the Sun does not burn the Earth because
a) the gas of the corona is too thin and transparent for it to be a
blackbody
32. The spectrum lines of an atom are produced by changes in the energies of
the atom's
e) electrons
33. Counting outward from the ground orbit (as 1), which orbit serves as the
lower level of the red hydrogen-alpha absorption line (part of the visible
Balmer series)?
b) 2
34. What ion or atom has a spectrum exactly like that of neutral helium?
e) none of them
35. The temperature of the solar photosphere is about
b) 6000ųK
36. The northern and southern lights are caused by
d) the solar wind and coronal mass ejections hitting Earth
37. The diameter of the Sun is how many times that of the Earth?
b) 100
38. The percentage of helium atoms (by number) in the outer solar layers is
closest to
a) 10%
39. The most abundant element in the Sun is
b) hydrogen
40. Solar granulation is caused by
e) convection
41. The Sun's magnetic field is generated by
c) its differential rotation and convection
42. Sunspots are regions of
a) strong magnetism
43. The hydrogen absorption lines in the Sun are weaker than the ionized
calcium lines because
d) the hydrogen lines come from excited orbits, whereas the calcium
lines come from the ground state
44. The average length of the solar magnetic cycle (over which the Sun returns
to the same magnetic configuration) is
d) 22 years
45. Solar neutrinos are produced in
e) the proton-proton chain in the solar center
46. Complete the reaction 2H + 1H
e) 3He
47. A third magnitude star is what relative to a eighth magnitude star?
c) 100 times brighter
48. The parallax of a star is 0.01 seconds of arc (0.01"). How far away is
it? away?
c) 100 parsecs
49. The proper motion of a star (its angular motion across the line of sight)
is inversely proportional to its
e) distance
50. The distance to the nearest star (Alpha Centauri) is closest to
c) 1 parsec