Q&A Hero

Q: Hubble's law is the major basis for the concept that the universe is A) static. B) evaporating. C) contracting. D) expanding.

Q: Most cosmologists favor the Big Bang theory over other cosmological theories because of A) a 3-to-1 ratio of hydrogen to helium in stars and interstellar matter. B) cosmological redshifts. C) the cosmic microwave background. D) all of the above.

Q: The universe seems to be about how many years old? A) 232 billion B) 6 billion C) 13.7 billion D) 1 billion

Q: The most distant objects yet detected in the universe are A) quasars. B) pulsars. C) superclusters. D) globular clusters.

Q: In a halo around the Milky Way's nuclear bulge lie about 200 A) brown dwarfs. B) quasars. C) red supergiants. D) globular clusters.

Q: Which of the following is an irregular galaxy that can be seen from the Southern Hemisphere? A) The Crab Nebula B) The Sagittarius Dwarf C) The Small Magellanic Cloud D) The Horsehead Nebula

Q: The Andromeda Galaxy (M31) is what type? A) Spiral B) Irregular C) Elliptical D) Regular spiral

Q: What astronomer established the present system for classifying galaxies? A) Henrietta Leavitt B) Harlow Shapley C) Edwin Hubble D) Hipparchus

Q: What type of galaxy is the Milky Way? A) Spiral B) Elliptical C) Regular D) Irregular

Q: Our solar system lies about how many light-years from the center of the nuclear bulge of the Milky Way? A) 2400 B) 28,000 C) 110 D) 4.3

Q: The longest diameter of the Milky Way is about how many light-years? A) 10 B) 10,000 C) 100 D) 100,000

Q: The estimated number of stars in the Milky Way is about how many billion? A) 1 to 2 B) 100 to 200 C) 10 to 20 D) 1000 to 2000

Q: Which of the following is nota name used in the classification of galaxies? A) Irregular B) Regular C) Spiral D) Elliptical

Q: When the term singularityis mentioned, the object under discussion is probably a A) white dwarf. B) black hole. C) neutron star. D) nova.

Q: Which of the following is thought to be a black hole? A) Gleise 229B B) Sirius B C) Orion Nebula D) Cygnus X-1

Q: In the middle of the Crab Nebula (M1) is A) a black hole. B) a pulsar. C) a quasar. D) a white dwarf.

Q: The explosion of a Type II supernova leaves behind A) just a black hole. B) a neutron star or a black hole. C) just a neutron star. D) none of the above.

Q: A faint white dwarf that temporarily increases in brightness as a consequence of nuclear explosions on its surface is termed A) a nova. B) a Type II supernova. C) a bright nebula. D) a red giant.

Q: The radial distance to the event horizon from the singularity of a black hole is called A) the Roche limit. B) the Schwarzschild radius. C) the Hubble unit. D) none of the above.

Q: The end stage of the life cycle of an extremely high-mass star is a A) quasar. B) neutron star. C) black hole. D) white dwarf.

Q: Brown dwarfs are often described as A) quasars. B) giant planets. C) failed stars. D) pulsars.

Q: Sirius is a binary star, consisting of Sirius A and Sirius B. Sirius B is a A) red giant. B) white dwarf. C) planetary nebula. D) neutron star.

Q: For low-mass stars, the life cycle phase that just precedes white dwarf formation is A) planetary nebula. B) variable star. C) main-sequence star. D) red giant.

Q: Stars in the process of forming are called A) giant planets. B) brown dwarfs. C) red supergiants. D) protostars.

Q: What type of nebula is the Horsehead? A) Primitive B) Bright emission C) Bright reflection D) Dark

Q: The two major types of nebulae are A) emission nebulae and dark nebulae. B) bright nebulae and dark nebulae. C) bright nebulae and reflection nebulae. D) reflection nebulae and emission nebulae.

Q: The next phase in the life cycle of the Sun will be A) the formation of a red giant. B) a move to the main sequence. C) collapse to a white dwarf. D) a supernova explosion.

Q: The Sun has been on the main sequence A) for about 10 million years. B) for about 5 billion years. C) forever. D) for about 14 billion years.

Q: The Sun will finally become a A) brown dwarf. B) neutron star. C) black hole. D) white dwarf.

Q: What spectral class of star fits between a type G and a type M? A) L B) K C) A D) F

Q: White dwarfs are relatively A) hot and dim. B) cool and dim. C) hot and bright. D) cool and bright.

Q: What color are the stars with the hottest photosphere? A) White B) Yellow C) Red D) Blue

Q: The name of which astronomer is most closely linked with that of Henry Russell? A) Henrietta Leavitt B) Johannes Kepler C) Ejnar Hertzsprung D) Edwin Hubble

Q: The name of which astronomer is most closely linked with that of Ejnar Hertzsprung? A) Johannes Kepler B) Henrietta Leavitt C) Henry Russell D) Edwin Hubble

Q: The absolute magnitude of a celestial object is the apparent magnitude it would have if it were placed how far from the Earth? A) 10 parsecs B) 3.26 light-years C) 1 astronomical unit D) None of the above

Q: The brightest planet has an apparent magnitude of about " 4 and is named A) Jupiter. B) Saturn. C) Mars. D) Venus.

Q: The brightest star (apparent magnitude "1) in the night sky in the Northern Hemisphere is named A) Polaris. B) Sirius. C) Deneb. D) Alpha Centauri.

Q: If the magnitude difference between one star and another is 8, the stars differ in brightness by a factor of A) 2.51. B) 20. C) 7. D) 1580.

Q: If the magnitude difference between one star and another is 4, the stars differ in brightness by a factor of A) 2.51. B) 10. C) 3. D) 39.7.

Q: If the magnitude difference between one star and another is 5, the stars differ in brightness by a factor of A) 2.51. B) 10. C) 4. D) 100.

Q: If the magnitude difference between one star and another is 1, the stars differ in brightness by a factor of A) 10. B) 100. C) 2.51. D) 4.

Q: Stars of what magnitude are just barely visible to the unaided eye? A) 4 B) 6 C) 2 D) 0

Q: Antiquity's greatest observer of stars was named A) Hipparchus. B) Eratosthenes. C) Aristotle. D) Imhotep.

Q: Taurus the Bull is a(n) A) star. B) asterism. C) galaxy. D) constellation.

Q: The Big Dipper is a(n) A) cluster of galaxies. B) constellation. C) galaxy. D) asterism.

Q: How many constellations encompass the complete celestial sphere? A) 88 B) 360 C) 180 D) 100

Q: In a star, the balance between the inward force of gravity and the outward force of thermal and radiation pressure is called A) the neutrino bonding point. B) hydrostatic equilibrium. C) the plasma equality condition. D) strong nuclear binding.

Q: Familiar groups of stars that are parts of a constellation or parts of different constellations are called A) configurations. B) asterisms. C) major sequences. D) local groups.

Q: The closest star to the Sun is named A) Polaris. B) Sirius. C) Betelgeuse. D) Proxima Centauri.

Q: The closest star to the Sun is about how far away? A) 17.7 light-years B) 0.52 light-years C) 33.6 light-years D) 4.3 light-years

Q: The majority of stars are small, cool, type-M stars called A) brown dwarfs. B) blue dwarfs. C) red dwarfs. D) white dwarfs.

Q: The apparent brightness of stars is ranked according to magnitude. The brightest stars were originally ranked as what magnitude? A) Zero B) Sixth C) First D) None of the above

Q: Stars lying above the main sequence that are relatively cool but very bright are called A) red giants. B) white dwarfs. C) brown dwarfs. D) pulsars.

Q: The color of a star reveals its A) apparent brightness. B) component elements. C) density. D) surface temperature.

Q: The Sun has an apparent magnitude of about A) minus 1.4. B) minus 27. C) 1.4. D) 15.6.

Q: Taking the reciprocal of a star's parallax angle in arcsec gives the star's A) energy output in joules. B) absolute magnitude in watts. C) solar constant in watts. D) distance in parsecs.

Q: The apparent motion of an object when it is viewed from two different positions against a fixed background is called A) Hubble's effect. B) parallax. C) paradox. D) Brighton's effect.

Q: Which of the following represents the shortest distance? A) One parsec B) One astronomical unit C) One light-year D) One right ascension

Q: Which of the following represents the longest distance? A) One parsec B) One astronomical unit C) One light-year D) One right ascension

Q: One parsec is equivalent in distance to how many light-years? A) 3.26 B) 1.61 C) 1.00 D) 4.35

Q: Celestial longitude is called A) declination. B) the parsec value. C) the zenith angle. D) right ascension.

Q: Celestial latitude is called A) declination. B) right ascension. C) the parsec value. D) the zenith angle.

Q: The apparent path that the Sun traces annually along the celestial sphere is called the A) ecliptic. B) heliosphere. C) solstice circle. D) celestial prime meridian.

Q: Twelve hours of daytime and twelve hours of nighttime occur at every location on Earth whenever the Sun reaches the A) north or south celestial pole. B) celestial prime meridian. C) vernal or autumnal equinox. D) ecliptic.

Q: The half-circle that defines the starting point for designating longitude on the celestial sphere is called the A) vernal equinox. B) ecliptic. C) celestial prime meridian. D) Greenwich meridian.

Q: One parsec is defined as the distance to a star when the star exhibits a parallax of what angle of arc? A) One degree B) One second C) One millimeter D) One minute

Q: The celestial prime meridian is an imaginary half-circle running from the north celestial pole to the south celestial pole and crossing perpendicular to the celestial equator at the point of the A) autumnal equinox. B) summer solstice. C) vernal equinox. D) winter solstice.

Q: Astronomers measure stellar distances in three different units. The smallest of these is A) the light-year. B) the absolute magnitude. C) the astronomical unit. D) the parsec.

Q: The stellar parallax of many stars is too small to be measured. This is evidence that these stars A) move in very small orbits. B) are almost in line with the Sun. C) are very distant. D) do not move.

Q: The celestial equator is A) a great circle. B) coplanar with the terrestrial equator. C) perpendicular to lines of right ascension. D) all of the above.

Q: It is nottrue that right ascension is A) measured in units of hours, minutes, and seconds. B) an angular measurement. C) a coordinate for measuring celestial longitude. D) how high a star is above the celestial equator.

Q: The three space coordinates that determine a star's position are the A) celestial sphere, celestial prime meridian, and celestial equator. B) zodiac, constellation, and star name. C) distance, declination, and right ascension. D) astronomical unit, parsec, and light-year.

Q: Enormous filaments of excited gas arching over the Sun's surface and extending hundreds of thousand of kilometers outward are called A) sunspots. B) solar flares. C) prominences. D) coronal arcs.

Q: What elementary particle has no charge, travels at or near the speed of light, and hardly ever interacts with other particles? A) Positron B) Plasmon C) Deuteron D) Neutrino

Q: The three fusion reactions in the Sun that form helium from hydrogen are together called the A) proton-proton chain. B) hydrogen cycle. C) helium sequence. D) neutrino exchange.

Q: The Sun projects charged particles into space, giving rise to a flow of radiation called the A) heliosphere. B) solar wind. C) corona. D) chromosphere.

Q: The Sun's high-speed charged nuclei and electrons form a fourth phase of matter known as a A) neutrino. B) sunspot. C) plasma. D) fusion pool.

Q: What is the name of the Sun's outermost solar atmosphere, which can be seen during a solar eclipse? A) Solar wind B) Heliosphere C) Photosphere D) Corona

Q: The sunspot cycle has a period of A) 19 years. B) 11 years. C) 38 years. D) 24 years.

Q: The Sun is a A) moon. B) galaxy. C) planet. D) star.