The ecliptic: occurs during a solar or lunar eclipse. is the average distance between the Sun and Earth. is the plane of Earth's orbit. refers to the gases from which our solar system formed.
Nebular theory pertains to the formation of: the solar system. a galaxy. the asteroid belt. the Earth.
A cloud of interstellar gas is held together by: the gravitational force.
infrared radiation.
electromagnetism.
All of the above.
A spinning cloud of interstellar gas tends to: disperse.
flatten.
turn into a sphere.
condense.
How long does it take for Earth to orbit the Sun?
one day one week one month one year.
The Sun tends to bloat outward by nuclear fusion, and contract due to: gravitation.
nuclear fission.
mass decrease.
its relatively slow spin.
reduced gaseous pressures.
Each second, the burning Sun's mass: decreases.
increases.
remains unchanged.
The age of the Sun is about 7000 years.
5.5 million years.
5.5 billion years.
5.5 trillion years.
more than 5.5 trillion years
Temperature differences between nighttime and daytime on Earth are relatively small due to: polar regions absorbing most solar energy.
B ) Earth being 70% water.
Earth's relatively high daily spin rate and shortness of nighttime.
seasonal fluctuations and Earths magnetic field.
The carbon dioxide cycle is important to Earth because it: helps sustain the planet's plant base.
has been recognized by the Nobel Prize award committee.
and the oceans are critical in moderating and regulating the Earth's temperatures.
prevents the gradual buildup of oxygen, which would eventually lead to a combustible atmosphere.
The planet with a mass most like Earth's is: Mercury.
Venus.
Mars.
Saturn.
Neptune.
The predominant gas in the atmosphere of Earth is: oxygen.
nitrogen.
water vapor.
carbon dioxide.
methane.
On which body (other than Earth) is life in our solar system most likely to be found?
Mars Venus Europa Scientific evidence suggests that life elsewhere in our solar system is not possible.
Which body in the solar system has the highest level of volcanic activity?
Jupiter Earth Mars Io (a moon of Jupiter)
What makes Europa the most likely place extraterrestrial life will be found in our solar system? It has an ocean of liquid water, which is warmed by tidal force interaction with Jupiter, and may house underwater volcanic thermal vents. It has an ocean of liquid water, and there is increasing evidence of phytoplankton activity, particularly as shown by ongoing spectral analysis. It has a hydrogen ocean and moderate levels of oxygen in its atmosphere, which is gradually producing water through frequent lighting strikes. Actually, Io is the most likely place to find life, due to its high level of volcanic activity.
The parts of Saturn's rings with the greatest rotational speed are the: inner parts. outer parts. Neither, for all parts of Saturn's rings rotate equally.
Is the rate of Earth's rotation increasing or decreasing? It is increasing It is decreasing It is remaining relatively steady. It is increasing and decreasing in cyclic fashion.
Which explanation best describes why Earth observers always see the same face of the moon? The Moon's rate of spin matches the rate at which the Moon revolves around Earth. The Moon does not rotate as it circles Earth. We tend only to observe the Moon at night, not during the day. Earth and Moon are partially gravity locked.
Why should one not stare at the Sun during a partial eclipse?
Because, whether there is an eclipse or not, the Sun's intense radiation can easily damage our eyes.
Because the eclipse event itself creates a lensing effect, which greatly magnifies and intensifies the Suns rays.
Because
Sunspots, which are excited by the eclipse event, can easily erupt during the eclipse.
Because Ultraviolet radiation is intensified during the event.
Because coronas and corneas are always a bad mix.
Why is the Moon still visible during a full lunar eclipse?
Earth's atmosphere acts as a lens that refracts light into the shadowed region.
There is a minor component of phosphorescent minerals distributed fairly evenly on the lunar surface.
The Moon's thin atmosphere acts as a mirror, reflecting light being cast from neighboring stars.
Background microwave radiation becomes excited during the lunar eclipse, and shifts towards visual light, which then slightly illuminates the eclipsed moon.
The core of the Moon is: solid.
liquid.
gaseous.
Not enough information is known for an answer.
The Earth rotates about its axis once per 24 hours, while the Moon rotates about its axis once per: 24 hours also.
half month.
month.
year.
none of these
When the Moon assumes its characteristic thin crescent shape, the position of the Sun is: almost directly behind the Earth, so Earth is between the
Sun and the Moon.
almost directly in back of the Moon.
at right angles to the line between the Moon and Earth.
When the alignment of the Sun, the Moon, and Earth produce a solar eclipse, the body between the other two is the: Sun.
Moon.
Earth.
The reason we don't have solar and lunar eclipses monthly is because of the: relatively close distance of the Moon and Earth.
relatively long distance to the Sun.
tapering of the Sun's rays.
different orbital planes for Earth and the Moon.
23° tilt of the Earth's axis.
About how many tons of meteorites strike the Earth on a daily basis?
20 tons 200 tons 2,000 tons 20,000 tons
At about what frequency is Earth struck by a meteorite large enough (about 10 km in diameter) to cause mass extinctions?
About every 1 million years About every 10 million years About every 100 million years This has yet to occur on Earth
Between which planets is the asteroid belt found?
Between Mars and Jupiter Between Earth and Mars Between Earth and Venus Between
Jupiter and Neptune
For what reason was Pluto demoted from full planetary status in 2006?
Because of objects as large or larger than Pluto in the Kuiper belt Because
Pluto resides outside of the zone that can truly be described as the solar system Because Pluto was discovered to be a twin planet system
Because according to the standard definition, no planet can be smaller than the Earth's moon
Asteroids orbit the: Sun.
Earth.
Moon.
all of these none of these
Most meteors seen as shooting stars are about the size of : grains of sand.
baseballs.
small buildings.
very large buildings.
small continents.
A small rock in interplanetary space is called a: meteor.
meteoroid.
meteorite.
In a museum collection you can likely see a: meteoroid but not a meteorite.
meteor but not a meteoroid.
meteorite but not a meteoroid.
The North Star has very little apparent rotation in the night sky because: it lies directly above the Earth's axis of spin.
it rotates in the same relative orbit as Earth.
its rate of spin directly matches Earth's.
the Oort cloud distorts the view of the naked eye.
We say we are looking back in time when we are looking at the stars because: we see stars as they once were when their light reaches us.
space curves, we are actually looking at the past when we look in the night sky.
stars are emitting immense radiation, we are seeing processes that have already happened.
Earth's atmosphere bends and distorts their light.
Polaris is always directly overhead at: the north pole.
any location north of the equator.
the equator.
We do not see stars in the daytime because: the Sun blocks their view.
they simply don't exist in the daytime part of the sky.
skylight overwhelms starlight.
of the lack of contrast with moonlight.
the solar wind obscures their view.
What are the relative compositions of the materials from which stars form?
About 74% hydrogen, about 24% helium, no more than 2% other materials About 24% hydrogen, about 74% helium, no more than 2% other materials About 2% hydrogen, about 74% helium, no more than
24% other materials Stars have vastly differing combinations of materials.
Luminosity is: the total amount of light energy that star emits into space.
the stars apparent brightness.
the stars particular color spectrum output.
the stars total infrared output.
What is the reference that astronomers use to denote the luminosity of stars?
The luminosity of the Sun The luminosity of the Northern Star The luminosity of Proxima Centauri, our solar system's closest neighbor star The luminosity of the cluster of stars at the center of the Milky Way galaxy
Thermonuclear fusion occurs mainly in the: cores of stars.
outer layers of stars.
both, actually
The temperature of a star is evidenced by its: brightness.
color.
angular momentum.
distance.
rate of burning.
On the H-R diagram our Sun is a: white dwarf.
star of average luminosity and temperature.
red supergiant.
relatively bright, blue star.
Red giant stars are: close to exhausting their supply of hydrogen.
have already exhausted their supply of hydrogen.
are close to exhausting their supply of helium.
have already exhausted their supply of helium.
The event that changes a protostar to a full-fledged star is: gravitational collapse.
gravitational expansion.
thermonuclear fusion.
the emission of light.
a catastrophic increase in temperature.
The longest living stars are those of : low mass.
high mass.
intermediate mass.
The H-R Diagram, an important tool of astronomers, relates stellar temperature to stellar: distance.
mass.
color.
density.
luminosity.

A star's size stabilizes when: thermal pressure and gravitational attraction balance each other.
the star's gravitational attraction is balanced by the gravitational attraction to neighboring stars.
the star first ignites.
it reaches temperatures of about 3 million K.
The determining factor in the stages a star will progress through from birth to death is its: mass.
temperature.
composition.
relative density.
What event will eventually move an average star off the main sequence of the H-R diagram?
Running out of hydrogen, causing gravitational influx, resulting in core temperatures high enough to begin fusing helium Surface cooling due to hydrogen loss Solar wind storms Its drift through space due to the gravitational attraction of neighboring giant stars
Because a white dwarf is no longer burning fuel, it is more accurately described as being a: stellar remnant failed star protostar
The gold in Uncle Harry's teeth fillings originated in: the deep interior of the Earth.
fusion processes that date back about 5.5 billion years.
the
Big Bang.
stars that blew up eons ago.
Fort Knox.
After our Sun burns its supply of hydrogen, it will become a: white dwarf.
black dwarf.
black hole.
red giant.
blue giant.
The elements found on Earth have much to do with: white dwarfs.
neutron stars.
pulsars.
quasars.
supernovae.
A pulsar is likely a: throbbing star in its death throes.
black hole companion.
spinning neutron star.
binary star with a dark companion.
A black hole is: a region of space that is collapsed in on itself.
the result of the collapse of supergiant star.
likely found at the center of each spiral galaxy.
All of the above
A black hole has: about the same mass as the original star from which it formed.
infinite mass.
about half the mass of the star from which it formed.
a mass that widely fluctuates.
The event horizon of a black hole is: the surface below which no matter or energy can escape.
the surface where light becomes trapped in a circular orbit around the black hole.
the physical surface of the black hole.
the point in time when a black hole comes into being.
A black hole is: an empty region of space with a huge gravitational field.
a small region that has the mass of many galaxies.
the remains of a giant collapsed star.
When a star collapses to become a black hole, its : mass increases.
density increases.
volume increases.
One of Edwin Hubble's discoveries is that the known universe is expanding. This means that: most all observable galaxies are moving away from each other.
light rays bend as they near the event horizon of a black hole.
light rays undergo acceleration as they travel vast distances.
the mass of the universe is slowly dissipating.
Galaxies are aggregations of stars, stellar dust, and gas. Their masses: are all about the same, which is huge.
vary greatly from one galaxy to the next.
are small compared to blue supergiant stars.
depend on the rate of pulsar emissions within them.
A Starburst galaxy has this name because of its: high rate of star formation.
high rate of supernovae.
large number of pulsars.
large number of neutron stars.
Quasars are: ancient, extremely high energy galaxies believed to have formed in the early universe.
a conglomeration of pulsars within a galaxy.
a conglomeration of spiral galaxies.
white dwarfs that have undergone final collapse.
Our local group is composed of how many galaxies?
Less than 100 Less than 400 Less than 1,000 1,526
A supercluster is a: cluster of galactic clusters.
very large local cluster.
local cluster with at least 10,000 supergiant stars.
local cluster with at least 500 supermassive black holes.
The Milky Way is: a spiral galaxy.
an elliptical galaxy.
an irregular galaxy.
a galaxy in the making.
the remains of a galaxy that has run its life course.
Most of the stars in colliding galaxies: do not make contact with one another.
coalesce into larger stars.
exchange amounts of material in proportion to their masses.
end up as binaries.
undergo accelerated collapse.
Cosmology is the study of the overall structure and evolution of: the universe.
stars.
beauty.
galaxies.
Edwin Hubble discovered that the farther away a galaxy is the: faster it is receding from us.
more massive it is.
more energetic it is.
more black holes it contains.
The "Big Bang" refers to the: point in time in which the known (and perhaps knowable) universe came into being.
phenomenon of rapid chain reaction supernovae during the first 100 seconds of the universe.
time when our Sun will become a nova, rendering Earth into molten lava.
end of the universe when simultaneous supernovae will transform the universe into a supergiant black hole.
The Big Bang: took place within space.
marked the beginning of space and time.
occurred as a result of disturbances within the Large Magellenic cloud.
took place within time.
The difference between lightwaves approaching and lightwaves receding is: when approaching, light is bluer; when receding redder.
when approaching, light is redder; when receding bluer.
There is no difference.
According to calculations made by modern astronomers, the age of the universe is close to: 14 billion years.
7 billion years.
21 billion years.
6,000 years.
Cosmic background radiation refers to: uniformly distributed residual radiation that resulted from the Big Bang.
pockets of radiation found in certain quadrants of the observable universe.
the radiation emitted from galactic nuclei.
redshifted microwave radiation being emitted from the center of the universe.
Cosmic Inflation refers to: an extremely rapid expansion of the early universe that occurred in an extremely brief period of time.
the fact that there is an ever increasing energy cost in order for fusion within stars to occur.
the phenomenon of matter within the universe is becoming increasingly disordered.
is another way of referring to the Big Bang itself.
Spacetime is curved by: mass.
the force of gravity.
quantum fluctuations.
the vacuum force.
According to Einstein, gravity is not the force exerted by one object on another, but rather the: effect we witness when a large mass causes a curvature in the shape of spacetime.
force of attraction that exists between two objects.
effects of the graviton particle.
curvature of space caused by objects reaching the speed of light.
"Local observations made in an accelerated frame of reference cannot be distinguished from observations made in a gravitational field" is known as the principle of: equivalence.
equality.
equanimity.
interchangeability.
Light is without mass, so how can gravity have an effect on light?
The space through which the light passes is curved.
Photons actually have a very small mass, so gravity does have an effect on them.
When light interacts with particles, it loses some energy, and thus takes on some mass.
Gravity has no effect on light.
A greater gravitational field causes time to: speed up.
slow down.
fluctuate.
Gravity has no measurable effect on time.
According to relativity theory, it is possible to reverse time and grow younger when you: are near a black hole.
are near a very large gravitational field.
travel at nearly the speed of light.
you can never grow younger.
Dark Matter is matter that: cannot be seen, felt, or measured.
cannot be seen or felt, but can be measured through its gravitational effects.
is Dark
Energy's complement.
is found within a black hole.
Evidence for dark matter is exhibited by the: relatively similar speeds at which all stars in a galaxy orbit the galactic nucleus.
speed at which galaxies orbit one another within clusters.
degree to which galaxy clusters exhibit gravitational lensing effects.
All of the above
According to dark matter theory, most of the mass of a spiral galaxy is found: within the central supermassive black hole.
within the luminescent spiral arms.
outside of the luminescent spiral arms.
in the form of dark energy.
Distant galaxies are: growing closer to each other as they encounter the curvature of the universe.
accelerating away from each other.
slowing in their dispersal due to the effects of gravity.
connected to each other by dark energy.
Dark energy: is the phenomenon responsible for the acceleration of the universe.
would be considered to be the opposite of gravity.
is energy that exerts an outward pressure, causing spacetime to expand.
All of the above
Heat death refers to the universe: reaching the lowest energy state possible.
ending after a massive fire.
reaching a state where all stars expand and merge into each other.
reaching the point where the process of radioactive decay is no longer possible.
Eternal Inflation refers to: the possibility that our universe is only a patch of a greater universe and that the process of universe spawning will continue forever.
the observation that cosmic inflation could eventually curve back in on itself, causing its opposite: the compression of space.
cosmic inflation inflating itself such that its own inflation is self-generating.
the presence of a distinct beginning of time.