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vary in both temperature and radius

A Cepheid variable star

a brown dwarf.

A cloud fragment too small to sustain nuclear fusion is:

We see the galaxy the way it was one billion years ago.

A galaxy is at a distance of one billion light years. Which of the following is true?

it generates more heat and its core eventually collapses very suddenly.

A high-mass star dies more violently than a low-mass star because:

short−duration gamma−ray bursts.

A hypernova creates a

large mass

A neutron star's immense gravity is primarily due to is small radius and its

is less luminous.

A nova differs from a supernova in that the nova

d. All of the given options are possible.

A proposed explanation for gamma-ray bursters is a. coalescence of a neutron star binary. b. hypernova-making black holes and bi-polar jets. c. star quakes in magnetars. d. All of the given options are possible.

nova

A surface explosion on a white dwarf, caused by falling matter from the atmosphere of its binary companion, creates what kind of object?

thousands

About how many planets have been found outisde our solar system orbiting other stars?

Solar Corona

Above the transition zone is the Sun's thin, hot upper atmosphere

early in the evolutionary sequence.

According to current theories of galactic evolution, quasars occur

The Universe has no center

According to modern theory, which of the following is true about the location of the center of the Universe?

d. Andromeda

All of the following are clusters of galaxies EXCEPT: a. Coma b. Virgo c. Hydra d. Andromeda

stellar evolution

All stars live and die through a process called

b. all of the above

Angles can be measured by which of the following units? a. I don't know b. all of the above c. degree d. arc second e. arc minute

structure of "clumping" due to filaments and voids.

As we look at larger and larger scales of the visible universe, we find

1000

Astronomers have confirmed the existence of about _______ planets beyond our solar system.

galaxies farther away are moving away from us faster.

Astronomers know the universe is expanding because

solar wind

At a distance of about 15 solar radii, the gas in the corona is hot enough to escape the Sun's gravity, and the corona begins to flow outward as the ___ ___.

comprises over 90% of the entire mass of the universe.

Based on galactic rotation curves and cluster dynamics, we think dark matter

True

Cepheid variables and type I supernova are used as "standard candles" to find distances.

True

Collisions between galaxies is thought to be commonplace.

fainter

Compared with a star of apparent magnitude of -2, a star of apparent magnitude of 0 is

brighter

Compared with a star with a magnitude of +2, a star with a magnitude of -1 is

that it makes up 95% of the universe.

Concerning dark matter and energy, we do know

dark matter not made of protons and neutrons.

Currently, most of the mass of the matter of the universe is believed to consist of

False

Gravity slows the expansion of the universe; dark matter accelerates it.

the Cosmological Principle.

Homogeneity and isotropy, taken as assumptions regarding the structure and evolution of the universe, are known as:

We have no theory capable of addressing this question

How hot was the universe at time zero?

about 11 years

How long does the sunspot cycle last on average?

8

How many planets are in our solar system?

gravitation and pressure

Hydrostatic equilibrium in our Sun is the balance between

most galaxies are moving away from it.

If an alien astronomer in a distant galaxy looks at the galaxies it can see, it will observe that

type I supernova.

If it gains sufficient mass, a white dwarf can become a

average lifetime of a civilization.

If we are optimistic in our assumptions about the development of life and intelligence, then the number of technological civilizations in the galaxy should equal the

c. Europa

In addition to Mars, which Jovian moon shows some promise of life, with a surface not that different from the Arctic Ocean? a. Titan b. Triton c. Europa d. Io

d. all of the above

In comparing our own solar system with others found to date, we find: a. jovians often lie much closer to their suns than ours do. b. that most orbits are less circular than planets around our Sun. c. multiple planets are found in some systems. Incorrect d. all of the above

if the beam sweeps across us, we will detect a pulse of radiation.

In the Lighthouse model:

Standard Solar Model

Model that best fits the observed properties of the Sun

radio wavelengths.

Most SETI searches are done at

Chromosphere

Most of the absorption lines seen in the solar spectrum are produced here

dark matter out in the Halo

Most of the mass of the Milky Way seems to exist in the form of

coronal holes

Most of the solar wind flows outward from low density regions of the corona called ___ ___.

in a cluster of stars.

Most stars, probably all stars, formed...

age

Noting the turnoff mass in a star cluster allows you to determine its

create elements up to and including carbon

Nuclear fusion in the Sun will

strong nuclear force

Nuclei are held together by ___ ___ ___.

a super massive black hole

The object located at the center of the Galaxy is believed to be:

halo

The oldest stars in the galaxy are located in the

Main sequence, red giant, planetary nebula, white dwarf

The order of evolutionary stages of a star like the Sun would be?

brown dwarf, white dwarf, neutron star, black hole

The order of mass from lowest to highest is

Henrietta Leavitt

The period-luminosity relation was discovered in 1908 by

the fusion of hydrogen into helium

The primary source of the Sun's energy is...

we detect fewer solar neutrinos than we expect.

The solar neutrino problem is that...

O, B, A, F, G, K, M

The spectral class from highest temperature to lower temperature is:

spiral barred

The structure of our Milky Way is most similar to

T Tauri phase.

Stage 4 of star formation is when the object can exhibit violent surface activity producing extremely strong protostellar winds. This phase is also called the...

Star A has a larger radius.

Star A and star B both have the same temperature, but star A has a larger luminosity. What can you infer about the stars?

True

Stars form from a collapsing cloud that fragments into smaller and smaller pieces.

magnetic field rises and falls.

Sunspot cycle occurs as the...

magnetism

Sunspots are regions of intense ___.

True

Supermassive black holes may play a role in the formation and evolution of galaxies.

solar cycle

The 22-year cycle that results when the direction of the field is taken into account is called the solar cycle.

hydrogen and helium, but nothing else.

The Big Bang formed

the upper mass limit for a white dwarf.

The Chandrasekhar Limit is

noting the gravitational influence of a planet on the star's motion

The Doppler shift method finds extrasolar planets by

the number of technical civilizations in our galaxy presently

The Drake equation calculates N. What is N?

225 million years.

The Galactic Year, the time for our solar system to orbit the Galaxy, is about

luminosity

The Hertzsprung-Russell Diagram plots ________ against the spectral type or temperature.

is, in terms of the star's gravity, its "zone of influence."

The Roche lobe of a star in a binary star system...

rotation

The Tully-Fisher relation exists between the galaxy's luminosity and its

ten parsecs.

The absolute magnitude of a star is its brightness as seen from a distance of:

Solar constant

The amount of solar energy reaching a 1 m^2 at the top of Earth's atmosphere each second

red giant branch

The asymptotic giant branch is similar to the

an astronomical unit

The average distance between the Earth and the Sun is called

the inflationary epoch.

The best answer to both the flatness and horizon problems is

does not exist anywhere in space.

The center of the universe

type I supernovae

The critical evidence for cosmic acceleration in 1998 came from two teams of astronomers, both observing:

it was was experimental verification of a prediction from the Big Bang theory.

The discovery of the cosmic microwave background was important because

Granulation

The effect of the solar convection zone can be seen on the surface in the form of ___.

Frank Drake

The equation that estimates the factors which determine how many technological civilizations are present in our galaxy was developed by _______.

increasing

The expansion rate of the Universe is

True

The first planet directly imaged was Fomalhalt b.

Pioneer 10

The first probe carrying mankind's message to alien civilizations was:

the longer ago it existed.

The further away a galaxy is

find a planet like Earth

The goal of the Kepler mission is to

temperatures are suitable for planets to have liquid water.

The habitable zone is the area around a star where:

during a type II supernova explosion.

The heaviest nuclei of all are formed

mass.

The main factor that influences where a star appears on the main sequence is

Core

The main interior region of the Sun where nuclear reactions generate energy.

flares

The more intense ___ are violent surface explosions that blast particles and radiation into interplanetary space.

Nuclear fusion

The sun generates energy by converting hydrogen to helium in its cor by the process of nuclear fusion.

perform an experiment

The third step in the scientific method is

Luminosity

The total amount of energy radiated from the solar surface per second.

the interior structure of the Sun.

The vibrations of the Sun reveal information about...

Jovian Planets

They are usually primarily composed of low-boiling-point materials, rather than rock or other solid matter, but massive solid planets can also exist.

Novae

To which of these phenomena are X-ray busters most similar?

cooled off white dwarfs that no longer glow visibly

What are black dwarfs?

found in the plane of the galaxy

What are the characteristics of an open cluster of stars?

luminosity, mass, and radius

What are the intrinsic properties of stars?

Nothing

What can we detect from matter that has crossed an event horizon?

The horizon problem in that the microwave background is almost too isotropic

What did the cosmic microwave background tell cosmologists about the early universe?

amino acids

What important molecules of life did Miller and Urey brew up?

There is no longer nuclear fusion in its core.

What inevitably forces a star like the Sun to evolve away from being a main sequence star?

the ejected envelope of a red giant surrounding a stellar core remnant

What is a planetary nebula?

The corona is much hotter than layers of the Sun that are closer to the solar interior

What is it about the Sun's corona that astronomers don't understand?

high temperatures

What is needed for nuclear fusion to occur?

Radiation pressure from nuclear fusion

What is the force that keeps a main sequence star from collapsing on itself?

The universe will expand forever

What is the meaning of a "open" universe?

Hydrogen

What is the most abundant element in the Sun?

a red giant, a nova, a type I supernova, a type II supernova

What is the order of visual luminosity from least to most luminous?

13.8 billion years

What is the presently accepted value for the age of the universe?

Mass

What is the single most important characteristic in determining how long a star lives?

The arms orbit the center.

What is true of spiral galaxies?

It is the remnant of a supernova observed by humans.

What makes the Crab Nebula supernova remnant unusual as a supernova remnant?

the galactic disk

What part of the galaxy is the solar system located?

They believed that the Milky Way was the entire universe.

What perception of the Milky Way Galaxy did astronomers have in 1900?

The collapse of part of an interstellar cloud of gas and dust.

What process is reponsible for the formation of a new star?

d. all of the above

What triggers might have made part of an interstellar cloud begin to contract? a. supernova b. density waves c. shockwave d. all of the above

it contains amino acids

What unusual discovery was made about the Murchison Meteorite?

a theory incorporating all four forces

What would help scientists probe the period from zero time to 10-43 second?

proton-proton chain

When four protons are converted to a helium nucleus in the ___ ___ ___, some mass is lost.

New

When the Moon appears to cover the Sun (a solar eclipse), the Moon must be in what phase?

near the end of the 20th century

When was the first confirmed exoplanet discovered?

we can, by the drop in light, find the planet's size, mass, and density.

When we see an extra-solar planet transit its star

Convection zone

Where the Sun's matter is in constant convective motion.

Radiation zone

Where the energy travels outward in the form of electromagnetic radiation

Galileo

Which astronomer's observations with the telescope showed that the Earth is not the center of the solar system?

fusion of hydrogen atoms into helium atoms

Which event marks the birth of a star?

tightly bound

Which is characteristic of globular star clusters?

e. all are methods for detecting exoplanets

Which is not a method for detecting exoplanets? a. direct imaging b. radial velocity c. transit d. microlensing e. all are methods for detecting exoplanets

in the disk, and about half way out from the center

Which is the correct description for the Sun's location in the Galaxy?

Earth, Venus, Mars, Mercury

Which of the following are the terrestrial planets?

sizes of HII regions

Which of the following is not a way to determine distance to objects in astronomy? Select one:

red dwarfs

Which of the following is the most common type of star?

a. speed

Which of the following is the same for an electromagnetic wave in space? a. speed b. I don't know c. frequency d. wavelength e. energy

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Which of the following lists is correctly arranged in order from closest to furthest from the Sun?

The greater the distance to a galaxy, the greater its redshift.

Which of the following paraphrases Hubble Law?

d. O

Which of the following spectral class for stars corresponds to the hottest star? a. A b. B c. G d. O

Jovians have a higher density than the terrestrials.

Which of the following statements is NOT true in the way that terrestrial and Jovian planets differ?

coronal mass ejections

Which of these active regions have the most energy?

The two types are both closely related to evolution of white dwarfs.

Which of these is NOT true about supernovae?

planetary nebula

Which of these will the Sun probably become in the very distant future?

It includes the Abell 1689 cluster.

Which statement about the Local Group is false?

Big Bang Theory

Which theory of the universe is accepted by most scientists?

There are likely to be an above average number of flares and prominences.

While observing the Sun, you not a large number of sunspots. What can you conclude?

electron degeneracy.

White dwarfs are kept from collapsing inward by...

Jocelyn Bell

Who discovered the first pulsar in 1967?

Penzias and Wilson

Who is credited with the discovery of the cosmic microwave background radiation:

Stars in clusters have the same age, similar composition, and are at the same distance away.

Why are star clusters almost ideal "laboratories" for stellar studies?

Their lifetime is too short

Why do we feel type O and B stars are poor candidates for extraterrestrial life?

d. All of the above.

Why was Herschel's strategy for mapping our Galaxy flawed? a. He assumed all stars have the same brightness. b. He did not account for extinction. c. He assumed the Sun was in the center. d. All of the above.

Edwin Hubble

______ proved that the spiral nebulae were other galaxies.

Guth

_______ is responsible for the inflation theory, which is a modification to the big bang.

Star

a glowing ball of gas held together by its own gravity and powered by nuclear fusion at its center

pulsar

a highly magnetized, rotating neutron star or white dwarf, that emits a beam of electromagnetic radiation.

solar constant

a measure of flux density, is the mean solar electromagnetic radiation (the solar irradiance) per unit area that would be incident on a plane perpendicular to the rays, at a distance of one astronomical unit (AU) from the Sun (roughly the mean distance from the Sun to the Earth).

transition zone

above the chromosphere, the temp increases from a few thousand to around a million kelvins.

Sunspots

are Earth-sized regions on the solar surface that are a little cooler than the surrounding photosphere.

Galactic halo

contains the oldest stars

Galactic bulge

contains the super massive black hole at the center

Neutrino oscillations

convert some neutrinos to other (undetected) particles en route from the Sun to Earth.

Galactic disk

has spiral arms

Coronal mass ejecions

huge blobs of magnetized gas excaping into interplanetary space.

Photosphere

is the region at the Dun's surface from which virtually all the visible light is emitted.

Prominences

looplike or sheetlike structures produced when hot gas ejected by activity on the solar surface interacts with the Sun;s magnetic field.

Neutrinos

nearly massless particles that are produce in the proton-proton chain and escape from the Sun. They interact via the weak nuclear force.

Law of conservation of mass and energy

requires that this mass appear as energy, eventually resulting in the light we see.

Terrestrial Planets

telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals.

Helioseismology

the study of vibrations of the solar surface caused by pressure waves in the interior provides further insight into the Sun's structure

extremophiles

Recently discovered organisms that create their energy through chemical reactions (chemosynthesis instead of photosynthesis) are:

active regions

Solar activity tends to be concentrated in ___ ___ associated with groups of sunspots.

True

From what astronomers can see, the geometry of the universe if flat.

nuclear fusion (combining of light elements to heavy)

From where does a star's energy, including the Sun's, come?

merging to form larger galaxies.

Galaxies evolve by

Radiation zone, convection zone, photosphere, chromosphere

From inside out, put the structure of the Sun in correct order: photosphere, chromosphere, radiation zone, convection zone

True

For active galaxies, the actual source of the energy emitted is accretion onto a supermassive black hole in the galactic nucleus.

supergranulation

Lower levels in the convection zone also leave their mark on the photosphere in the form of larger transient patterns called ___.

hydrogen and helium.

Nearly all the elements found in nature were formed inside stars, except for

neutron degeneracy

Neutron stars kept from collapsing inward by

an accretion disk of infalling matter

Not only does the central engine of active galaxies and quasars require a black hole, but also ________ to provide the radiate energy.

at the top right.

On the H-R diagram, red supergiants like Betelgeuse lie

...about the middle of the main sequence

On the H-R diagram, the Sun lies...

Earth, Solar System, Milky Way, Local Group, Virgo Supercluster

Order the following from smaller scale to larger.

Planck, GUT, Quark, Lepton, Nuclear

Order the radiation era epochs in correct order from the big bang.

the gravitational force

Present day Grand Unified Theory unifies all the fundamental forces except

particulate, galactic, stellar, planetary, chemical, biological, cultural

Put the seven phases of cosmic evolution in order.


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