In the sun the dominant energy producing reaction involves putting
A. electrons together.
B. protons together.
C. photons together.
D. neutrinos together.
ANSWER: 

In the process that stars use to generate energy,
A. large atoms are split into smaller ones.
B. neutrinos are made into atoms.
C. photons are converted into energy.
D. smaller, lighter nuclei combine to make heavier ones.
ANSWER: 

So far, all the different approaches for detecting solar neutrinos
A. give conflicting results.
B. agree that the sun seems to be producing too many neutrinos.
C. agree that the sun seems to be producing the expected quantity of neutrinos.
D. agree that the sun seems to be producing too few neutrinos.
ANSWER: 

Compared to smaller stars, massive stars use their fuel
A. much more efficiently and therefore have longer life spans.
B. much faster and therefore have shorter life spans.
C. more slowly and therefore have shorter life spans.
D. more slowly and therefore have longer life spans. 
ANSWER: 

The life span of a main sequence star with 2 Mo and 14 times more luminous than the sun is about
A. twice as along as the sun's life.
B. 14 times longer than the sun's life.
C. 14 times shorter than the sun's life.
D. 7 times shorter than the sun's life.
ANSWER: 

As main sequence stars like the sun use up the hydrogen in their cores, the core
A. collapses and cools; the surface expands and cools.
B. expands and cools; the surface expands and cools.
C. collapses and heats up; the surface expands and cools.
D. expands and heats up; the surface expands and cools.
ANSWER: 

Of the following main-sequence stars, the one that has the shortest main-sequence phase is type
A. O.
B. G.
C. M.
D. K.
ANSWER: 

During the main sequence stage, stars gradually become
A. fainter and cooler.
B. fainter but hotter.
C. brighter and hotter on the surface.
D. brighter and cooler on the surface.
ANSWER: 

A starlike object with low mass and too cool to sustain nuclear reactions in its core is known as a
A. white dwarf.
B. brown dwarf.
C. black dwarf.
D. red dwarf.
ANSWER: 

When changing from a main-sequence star into a giant star, a star's core
A. cools and its outer layers become hotter.
B. becomes hotter.
C. cools and its outer layers also become cooler.
D. becomes larger.
ANSWER: 

The upper limit for the mass of a star seems to be about
A. 100-150 Mo ; a larger mass would cause them to become very unstable and explode.
B. 100-150 Mo ; a larger mass would cause them to form Brown Holes.
C. 20 Mo ; a larger mass would cause them to collapse.
D. 20 Mo ; a larger mass would cause them to explode. 
ANSWER: 

Of the following types of stars, the one that has not been and cannot become a red giant is a
A. white dwarf.
B. red dwarf.
C. black dwarf.
D. Type ll supernova.
ANSWER: 

Planetary nebula are probably caused by
A. hydrogen fusion in shells (layers) around the core.
B. helium fusion in shells (layers) around the core.
C. a hot carbon-oxygen core.
D. a very compact core.
ANSWER: 

The most probable life cycle for the sun according to present theory would be
A. nebula - main sequence - planetary nebula - red giant - white dwarf.
B. main sequence - planetary nebula - red giant - white dwarf.
C. nebula - main sequence - red giant - planetary nebula - white dwarf.
D. main sequence - red giant - nova - white dwarf. 
ANSWER: 

A white dwarf in a binary system can pull gas off from its companion. Choose the most likely result.
A. This causes a planetary nebula to form around the companion.
B. The companion totally explodes creating a nova.
C. The companion's core becomes exposed causing it to explode.
D. Gas builds up on the surface of the white dwarf until it becomes hot enough to fuse creating a sudden and huge explosion.
ANSWER: 

A white dwarf is a
A. solid star about the size of Jupiter.
B. solid star about the size of the Earth.
C. very dense sphere of gases about the size of the Earth.
D. very dense star about the size of Jupiter.
ANSWER: 

An explosive, but non-destructive, event on the surface of a white dwarf that is part of binary system results in a
A. Type l supernova.
B. Type ll supernova.
C. nova.
D. planetary nebula.
ANSWER: 

Which of the following spectral classes are the least likely to form white dwarfs?
A. B.
B. G.
C. K.
D. M.
ANSWER: 

A Type ll supernova is created by the red supergiant stage of a massive star whose
A. iron core exploded
B. neutron core exploded.
C. iron core collapses.
D. neutron core collapses.
ANSWER: 

Choose the incorrect statement concerning Type II supernova.
A. Gases ejected from supernova explosions may help form new stars.
B. Nearby supernova events are rather rare, the last one occurred in 1987.
C. Large numbers of neutrinos are created.
D. All produce neurtron stars.
ANSWER: 

The swirling region of gas and dust that collects around a compact object, as its binary companion transfers material to it, is called
A. a supernova remnant.
B. a planetary nebula.
C. an event horizon.
D. an accretion disk.
ANSWER: 

At the end of a star's life, the battle between gravity and the outward internal pressure is
A. equalized as a balance between the two.
B. won by gravity.
C. won by pressure in a white dwarf and by gravity in a neutron star..
D. won by pressure.
ANSWER: 

Pulsars
A. are neutron stars that expand and contract in regular intervals.
B. can be any type of star that expands and contracts in regular intervals.
C. are neutron stars that spin fast.
D. can be any type of star that produces the "lighthouse effect".
ANSWER: 

A pulsar's energy is emitted
A. along the north and south axis (pole) of rotation.
B. along the north and south axis (pole) of its powerful magnetic field.
C. along the north and south axis (pole) of its strong gravitational field.
D. from the equatorial region only.
ANSWER: 

As pulsar age, their rate of spin tends to
A. speed up gradually due to the fact that the star shrinks in size.
B. slow down.
C. vary erratically due to loss of energy.
D. vary slightly up or down due to adjustments in the star's structure. 
ANSWER: 

The range in masses for neutron stars is
A. from about 1Mo to about 2.5Mo.
B. greater than 1.4Mo to about 2.5Mo.
C. greater than 1.4Mo to exactly 1.9Mo.
D. from 1Mo to exactly 1.9Mo.
ANSWER: 

Compared to a white dwarf, neutron stars have
A. much smaller diameters but are less dense.
B. larger diameters and are less dense.
C. larger diameters and are much denser.
D. smaller diameters and are much denser.
ANSWER: 

The perception astronomers have of black holes is
A. they are extremely dense, solid, black objects.
B. they are small (ten miles or so in diameter) spheres that will not allow light to escape because of their extreme gravitational pull.
C. they contain a singularly that is over one foot across.
D. have an event horizon that surrounds the ergosphere.
ANSWER: 

Which of the following is incorrect concerning the present theories about black holes?
A. The boundary (point of no return) is called the event horizon.
B. Near the event horizon, space itself is dragged along by a rotating black hole.
C. An infinitely dense singularity exists in the center.
D. Going into a black hole would also allow one to go back in time.
ANSWER: 

Choose the incorrect statement concerning black holes.
A. A person falling into a black hole would be greatly stretched.
B. Material falling towards a black hole is heated to millions of degrees.
C. Gamma rays are the only form of energy outside of neutrinos that can escape from a black hole.
D. X-rays may be emitted from an accretion disk that orbits a black hole.
ANSWER: 

The speed necessary to escape from a black hole
A. depends on the mass (diameter) of the black hole.
B. equals the speed of light.
C. is greater than the speed of light.
D. is infinite.
ANSWER: 

Black hole candidates are found by their emission of
A. ultraviolet light.
B. infrared light.
C. gamma rays.
D. x-rays.
ANSWER: 

If the sun was replaced with a one solar mass black hole, the gravity holding the Earth in orbit would become
A. stronger and Earth would be pulled in.
B. weaker and Earth would escape into space.
C. no different than it is now.
D. infinite.
ANSWER: 

Harlow Shapley was able to determine the Earth's approximate position in our galaxy by
A. measuring the magnitudes of Cepheid variables in the Magellanic Clouds.
B. noting we were in the center of a globular cluster.
C. studying the distribution of globular clusters around our galaxy.
D. measuring the distances of Cepheid variables in the Magellanic Clouds. 
ANSWER: 

Shapley determined distances across our galaxy by using the
A. Cepheid variable stars in globular clusters.
B. Cepheid variables in Population I groupings of stars.
C. Cepheid variables in open clusters.
D. distribution of heavy elements in stars around the galaxy.
ANSWER: 

Which of the following is a valid comparison of Population I and Population II stars?
A. Population I stars are older, bluer and in the disk or plane of our galaxy.
B. Population II stars are older, bluer and in the disk or plane of our galaxy.
C. Population I stars are younger, redder and in the disk or plane of our galaxy.
D. Population II stars are older, redder and in the halo around the bulge of our galaxy.
ANSWER: 

The approximate diameter of the disk of the Milky Way galaxy is
A. 5-10 million light years.
B. 1-2 million light years.
C. 75,000-100,000 light years.
D. 500-1,000 light years.
ANSWER: 

The stars found in the halo of our galaxy seem to be
A. richer in heavier elements.
B. mainly composed of just hydrogen and helium.
C. more variable in luminosity.
D. larger than those in the arms of the galaxy.
ANSWER: 

Stars, like our sun, that contain some heavy elements
A. are sometimes referred to as second or third generation stars because these heavy elements were produced in previous stars like supernovae.
B. are referred to as complex stars because of their composition.
C. must be very old to give time for these elements to be produced by nuclear reactions.
D. must be young or the nuclear reactions would have consumed them.
ANSWER: 

Choose the correct statement concerning the motions of stars in and around our galaxy.
A. Stars in the disk (arms) move randomly; halo stars move more randomly and in ellipses.
B. Stars in the disk (arms) move randomly; halo stars move much faster.
C. Stars in the disk (arms) move around the center; halo stars preserve their original (fossil) motion.
D. Stars in the disk (arms) move much faster; halo stars move in concentric circles.
ANSWER: 

Dust obscures a lot of the Milky Way but we can still map the spiral arms by studying the
A. radio waves emitted from gas clouds of unknown composition.
B. radio waves emitted from the dust itself.
C. radio waves emitted from neutral hydrogen clouds.
D. 21 centimeter lines emitted by the dust itself.
ANSWER: 

Stars seem to move faster and faster as one approaches the center of our galaxy. This is interpreted to mean that a strong
A. gravitational field from a 20-30Mo black hole is present.
B. gravitational field from a 2-3 million Mo black hole is present.
C. magnetic field from a 2-3 million Mo black hole is present.
D. magnetic field from a 20-30 Mo black hole is present.
ANSWER: 

In our galaxy, bright new stars are still forming
A. in the spiral arms.
B. between spiral arms.
C. in the central bulge.
D. in the halo.
ANSWER: 

The term metal as used by astronomers refers to
A. mainly iron, nickel, magnesium or copper.
B. mainly iron, nickel, lead or copper.
C. mainly iron, nickel, lead or magnesium.
D. elements heavier than hydrogen or helium.
ANSWER: 

Stars that have the lowest metal content are found in the
A. disk of the galaxy.
B. halo of the galaxy.
C. spiral arms of the galaxy.
D. nuclear bulge of the galaxy.
ANSWER: 

Of the following types of galaxies, the one that has a nuclear bulge, spiral arms and the most gas and dust is
A. EO.
B. E2.
C. E7.
D. Sc.
ANSWER: 

Some galaxies in the Local Group seem to be
A. moving at the same rate as the Milky Way.
B. randomly distributed between moving away and toward us.
C. moving away from us in a corkscrew manner.
D. moving slowly towards us.
ANSWER: 

According to the Hubble Law, if galaxy A is 5 times farther than galaxy B, then galaxy A is
A. approaching 5 times faster than galaxy B.
B. approaching 5 times slower than galaxy B.
C. receding 5 times faster than galaxy B.
D. receding 5 times slower than galaxy B.
ANSWER: 

If the Hubble constant equals 80 km/sec/Mpc and a galaxy has a recessional velocity of 800 km/sec, then its distance would be
A. 100 Mpc.
B. 10 Mpc.
C. 8 Mpc.
D. 64,000 Mpc.
ANSWER: 

Of the following events, the one that is the least likely consequence of the collision of two galaxies is
A. a burst of star formation within the galaxies.
B. collisions of stars within the galaxies.
C. a distortion of the appearance of the galaxies.
D. a merger of the galaxies.
ANSWER: 

Choose the correct statement concerning Hubble's Law.
A. Hubble's Law applies to the universe and indicates that greater red shifts mean a smaller universe.
B. Hubble's Law applies to the universe and indicates that greater red shifts mean a larger universe.
C. Hubble's Law applies directly to the galaxies and indicates that greater red shifts mean a smaller distance.
D. Hubble's Law applies directly to the galaxies and indicates that greater red shifts mean a greater distance.
ANSWER: 

From his study of galaxies, Hubble was able to show that
A. individual galaxies are expanding.
B. the universe is contracting.
C. the universe is expanding.
D. the universe is more than 10 billion years old but not over 16 billion years old. 
ANSWER: 

A typical galaxy contains about
A. one million stars.
B. 10 million stars.
C. 100 million stars.
D. 100 billion stars.
ANSWER: 

Choose the statement that gives some basic differences between spiral and elliptical galaxies.
A. Spirals contain more dust and gas between stars, they tend to be dimmer and bluer.
B. Spirals contain less dust and gas between stars; they tend to be brighter and bluer.
C. Spirals contain more dust and gas between stars, they continue to form stars.
D. Elliptical galaxies are usually larger, older and bluer. 
ANSWER: 

The Local Group is a cluster of galaxies that contains the Milky Way, the
A. Andromeda galaxy and about 20 other galaxies within a sphere, 3 million l.y. across.
B. Andromeda galaxy and about 20 other galxies within a sphere, 4 billion l.y. across.
C. Magellanic Clouds and about 20 other galaxies within a sphere, 4 billion l.y. across.
D. Magellanic Clouds and thousands of other galaxies within a sphere, 3 million l.y. across.
ANSWER: 

The irregular galaxy called the Large Magellanic Cloud is presently
A. merging with the Milky Way.
B. approaching the Milky Way head on.
C. orbiting the Milky Way and will merge with it in the future.
D. orbiting the Milky Way and will continue to do so.
ANSWER: 

If the Big Bang occurred 15 billion years ago, then the size of the observable universe
A. is definitely infinite.
B. could be infinite, if the universe is open.
C. is the size of the expansion of the universe in the last 15 billion years.
D. will increase as more powerful telescopes are made in the future.
ANSWER: 

Primordial background radiation from the Big Bang is observable at
A. ultraviolet wavelengths.
B. x-ray wavelengths.
C. gamma ray wavelengths.
D. radio microwave wavelengths.
ANSWER: 

If an expanding balloon covered with dots is used as a model for the universe, the
A. balloon represents galaxies and the dots, stars.
B. balloon represents space and the dots, stars.
C. balloon represents space and the dots, galaxies.
D. surface of the balloon represents the observable portion of space and the dots, stars.
ANSWER: 

For a universe expanding like a balloon, the center is
A. near our solar system.
B. the Milky Way.
C. towards the constellation Sagittarius.
D. nonexistent, there is no center of expansion.
ANSWER: 

The cosmic microwave background radiation is thought to be
A. the result of energy coming from distant galaxies in all directions.
B. the "relic"energy from the once very hot beginnings of the Big Bang.
C. from a few cooler clouds of gas at the fringes of the universe.
D. from warmer clouds of gas at the fringes of the universe.
ANSWER: 

According to the Big Bang theory
A. all matter, energy and space formed from a point (singularly) no larger than the head of a pin.
B. all matter and light started from some star-like object's explosion.
C. all matter and space started from some star-like object's explosion
D. energy and space exploded from a point hundreds of billions of years ago.
ANSWER: 

The most abundant element in the earliest universe was
A. helium.
B. carbon.
C. hydrogen.
D. beryllium.
ANSWER: 

In the early universe, cooling led to
A. the formation of matter.
B. increased radiation.
C. the destruction of matter.
D. the production of energy.
ANSWER: 

According to Hubble's Law, if galaxy A is moving ten times faster than galaxy B, it is also
A. ten times larger.
B. ten times smaller.
C. shifted ten times more toward the blue portion of the spectra.
D. ten times farther away. 
ANSWER: 
