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203 Cards in this Set

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If a telescope with an objective lens of 10-foot focal length is used with an eyepiece of 1/4 inch focal length, the resulting magnification will be...
480x
You are on a strange planet. You note that the stars do not rise and set, but circle around parallel to the horizon. Then you travel over the surface of the planet in a straight line for 4500 miles and find that at this new place the stars rise straight up from the horizon in the east and set straight down in the west. The circumference of the planet is...
18,000 miles
Orange light is of ______ than violet light.
lower frequence and longer wavelength
The horns of the crescent moon ALWAYS point...
away from the Sun.
At new moon the Earth would appear to an observer on the moon to be at _____ phase.
Full
When Venus has an elongation that is 20 degrees westward from the Sun, it is then visible...
as a morning star
What happens in our model of the atom when an emission line is formed?
An electron moves from a higher energy level to a lower one.
You live at 40 degrees north latitude. How often is the Sun directly overhead at noon in your hometown?
Never
The orbit of the Earth about the Sun defines a plane in space. The orbital plane between the Earth and the Sun is referred to as the...
ecliptic
Although the stellar constellations are of very ancient origin, they are still useful to modern astronomers...
for indentifying stars and designating locations on the sky.
The first person known to suggest the heliocentric model for the solar system
Aristarchus
Wrote a series of books called the Almagest in which the epicycle theory of the solar system is described in great detail.
Ptolemy
Discovered the three laws of planetary motion
Kepler
Compiled the most accurate set of naked eye positional observations of the planets that had ever been made up to his time (1600 AD)
Tycho Brahe
Made a remarkably good estimate of the circumference of the Earth during the second century BC
Eratosthenes
Used the orbits and eclipses of the moons of Jupiter to estimate the speed of light
Roemer
First used a telescope to observe the heavens in 1610
Galileo
Discovered the four large moons of Jupiter by direct observation
Galileo
Wrote the book De Revolutionibus Orbium Coelestium published in 1543
Copernicus
Formulated the law of gravitation, the laws of motion and the nature of light
Newton
constellation with the bright star...
Polaris
Ursa Minor
Rigel
Orion
Castor
Gemini
Betelgeuse
Orion
Deneb
Cygnus
Altair
Aquila
Procyon
Canis Minor
Pollux
Gemini
Aldebaran
Taurus
Sirius
Canis Major
The second most abundant element in the Sun
helium
The planet that rotates on its axis with a period almost identical to that of the Earth is
Mars
Stars at the upper left-hand end of the main sequence have which of these:
long lifetimes
small size
cool temperature
large mass
red color
large mass
Which kind of process, as a net result, supplies the energy of our Sun?
Hydrogen atoms are converted to helium through fusion.
Suppose you are at the Tropic of Cancer, which has a latitude of 23.5 degrees. The altitude of the north celestial pole as seen from your position is...
23.5 degrees
The temperature of the solar photosphere is about
5800 K
How many stars of 7th magnitude in a small cluster would it take if the cluster were to appear as bright as a single 1st magnitude star?
251
Which is least important to an astronomer for observing stars:
magnifying power
resolving power
ability to photograph or measure for long periods of time
light-gathering power
ability to aim the telescope in different directions
magnifying power
An eclipse of the sun can only occur when the moon is at...
new moon
Ten parsecs is the standard distance selected for the astronomical scale of...
absolute magnitudes
Suppose that the moon is seen in the sky some evening. The next evening, it will have moved...
to the east
How many constellations in the night sky are accepted by the IAU?
88
Observation of the shift of a star's spectrum toward the red or the blue (Doppler shift) enables us to determine the star's...
radial velocity
The differences observed in stellar spectra are due primarily to differences in...
temperature
The Zeeman effect describes what changes in spectral lines?
Line splitting due to intense magnetic fields.
Shepherd moon of Saturn
Pandora (or Prometheus)
moons of Mars
Phobos and Demos
Largest rocky surface of any known satellite
Ganymede
Pluto's moon
Charon
Moon of Neptune with a thin atmosphere
Triton
Earth's moon
the Moon
Moon of Saturn that resembles the "Death Star"
Mimas
Moon of Neptune with a retrograde orbit
Triton
Highest albedo of any solar system object
Enceladus
First orbited by Borman, Lovell, and Anders in 1968
the Moon
Large satellite of Jupiter with possible oceans of water under a layer of ice
Europa
Geologically diverse satellite of Uranus
Miranda
Innermost Galilean satellite
Io
Moon of Saturn with a thick atmosphere
Titan
Galilean satellite with sulphur volcanos
Io
Suppose you are at the equator which has a latitude of 0 degrees. The altitude of the north celestial pole as seen from your position is...
0 degrees
All stars of spectral type G2 have approximately the same...
temperature
All eclipsing binaries are also
spectroscopic binaries
Which kind of star has the greatest average density:
red giant
main sequence
white dwarf
neutron star
red super-giant
neutron star
Which of the following would you NOT expect to find in the spiral arms of a typical galaxy:
dust lanes
O and B stars
emission nebulae
open clusters
globular clusters
Globular clusters
Which is NOT a possible final stage of stellar evolution:
white dwarf
T Tauri stage
black hole
neutron star
pulsar
T Tauri stage
Which type of galaxy has a stellar disk, but has little dust or gas?
S0
What two observations of an object allow for a determination of the Milky Way's mass?
an object's velocity and distance from the galactic center
What characteristic is the same for all stars in a star cluster?
age
A good way to determine the distance of a DISTANT star cluster is to...
compare its H-R diagram with a standard H-R diagram
Which of these features is NOT characteristic of nuclear fusion:
plentiful energy source
four hydrogen atoms produce one helium atom (net result)
neutrons and positrons are produced
high temperature is needed to overcome elecrostatic repulsion
very large, radioactive nuclei are produced as waste products
very large, radioactive nuclei are produced as waste products
Which is NOT a characteristic of a red giant:
nearly depleted hydrogen fuel in the core
contracted stellar core
iron being formed into heavier elements
cool stellar exterior
expansion of the outer layers of the stellar atmosphere
iron being formed into heavier elements
How many stars of 11th magnitude in a small cluster would it take for the cluster to appear as bright as a single 6th magnitude star?
100
The Crab nebula is material blown off a _____, which was observed by the Chinese in 1054 AD. At its center we now observe a _____
supernova; pulsar
The constellations which are visible in the early evening gradually change throughout one year due to the...
revolution of the Earth about the Sun
On September 21, the right ascension of the Sun is about...
12 hours
The Ptolemaic system accounts for retrograde motion by...
having the planets travel on epicycles
The ancients thought that rest was the natural state for a material body. Newton's ____ law states that uniform linear motion is just as natural as rest.
first
Galileo discovered all of the following except:
the phases of Venus
stars too fain for the naked eye to see
sunspots
the planet Uranus
the four largest satellites of Jupiter
the planet Uranus
If a telescope with an objective lens of three-fot focal lenth is used with an eyepiece of 1/4 inch focal length, the resulting magnification will be...
144x
The law of universal gravitation was developed by...
Newton
The gravitational attraction between two bodies depends on the distance, r, between them. The attraction varies with the distance as...
1/r^2
Blue light is of _____ than red light.
higher frequency and shorter wavelength
Boston is 90 degrees east of Hawaii. If it is noon in Hawaii, in Boston it would be about...
sunset
Polaris, the North Star, does not appear to move in the sky because...
it lies approximately over the northern axis of the Earth
Which type of radiation has the least energetic photons:
violet light
infrared
radio waves
red light
x-rays
radio waves
In an object is moving toward you, what effect do you observe in the spectrum of that object?
it appears blue-shifted
For what is an interferometer used?
To improve the angular resolution of radio telescopes
What do all kinds of electromagnetic energy have in common?
all have the same speed in a vacuum
Which of these is the greatest distance:
one light-year
one parsec
one billion miles
distance from Earth to the Sun
distance to the planet Pluto
one parsec
Beyond 100 parsecs, the distances determined by the method of trigonometric parallaxes become very unreliable because...
the parallax angles become too small to measure accurately
How do the escape velocities of the jovian planets compare to those of the terrestrial planets?
the jovian planets have much higher escape velocities
What do we learn from the Doppler shift which we observe in the spectrum of a star?
the star's radial velocity
Would the moon be a good place to do astronomy?
Yes; no atmosphere
How many stars of the sixth magnitude would equal the brightness of a star of the first magnitude?
100
Why does a star of type G5 have many absorption lines in its spectrum due to metallic elements such as iron, silicon, titanium, etc., which a star of type B5 shows very few lines of such elements?
the B star is very hot and nearly all of its metallic atoms are ionized, which makes them incapable of absorbing photons having visible wavelengths
A star with a complete spectral type of B2V would be referred to as which:
lower main sequence
red supergiant
upper main sequence
blue supergiant
red giant
upper main sequence
What would Jupiter have needed to become a star?
More mass
The kind of star which shows strong evidence of molecules in its spectrum would be considered...
very cool
When the moon is at third quarter, what time will it rise?
midnight
The minor planets (asteroids) in general follow orbits that lie between the orbits of...
Mars and Jupiter
The most recent data from distant supernovae indicates that:
the expansion of the universe is speeding up
The Sun rotates once in approximately...
one month
a given meteor shower, like the Leonids...
is visible on approximately the same date each year
In general, the tail of a comet streams away from the comet in a direction...
away from the Sun
The so-called "cosmological principle" is simply the idea that the basic large-scale features of the universe...
are the same regardless of location
All of the following may be used to estimate the solar surface temperature except:
Wein's law
Kepler's laws
the Stefan-Boltzman law
Planck's law
Kepler's laws
Which o the following spectral types is hottest:
G8
G9
F1
F2
F3
F1
Sunspots are associated with distortions in the Sun's...
magnetic field
One wavelength that may provide contact with extraterrestrial civilizations is found at...
21 cm
Which are NOT intrinsic variable stars:
novae
RR Lyraes
Cepheids
eclipsing variables
Miras
eclipsing variables
Suppose that in the spectrum of a star the spectral lines are observed to be alternately single and then double in a periodic fashion. The star is probably...
a spectroscopic binary
Of the many complex molecules found in interstellar space, most are BASED on which element?
Carbon
The "helium flash" occurs at what stage in stellar evolution?
low mass stars as they become red giants
The absolute magnitude of the Sun is about...
5
The type of intrinsic variable stars usually knows as _______ stars have periods from several hours to about a day. They are often found in globular clusters, and for that reason they are sometimes referred to as cluster variables.
RR Lyrae
Cepheid variable stars are useful as distance indicators because they show a definite, simple correlation between the period of light variation and their...
average absolute magnitude
The observed slowing of a clock in the vicinity of a black hole is a prediction of...
general relativity
Globular clusters form...
a halo concentric with the center of our galaxy
The Pleiades cluster of stars is an excellent example of a...
galactic/open cluster
The time required for a photon to travel across our galaxy is about ______ years.
160,000
A star that is responsible for causing a nebula to fluoresce (i.e. emit an emission spectrum) is mostly likely a star of type...
O or B
How is a technologically advanced civilization characterized in the Drake equation?
A civilization that can communicate over interstellar distances
Which of the following is NOT found in the galaxy's spiral arms:
young star clusters
O and B stars
globular clusters
emission nebulae
globular clusters
A galaxy is at a distance of one billion light years. We see the galaxy...
the way it was one billion years ago
The nucleus of our galaxy is located in the direction of the constellation...
Sagittarius
Quasars have their distances measured by what technique?
Hubble Law
Pair production can occur if...
The energy of two photons is greater than the combined mass-energy of a particle-anti-particle pair
Arcturus is in the constellation...
Bootes
The Zodiac is...
The constellations through which the Sun appears to travel in one year
The Great Square is in the constellation...
Pegasus
Declination is measured north and south of the celestial equator in units of...
degrees
the declination of the north celestial pole is...
90 degrees
What was Copernicus' major contribution to astronomy?
claimed Earth is not the center of the universe
Two forms of electromagnetic radiation that penetrate the Earth's atmosphere are:
x-rays and visible light
gamma rays and radio waves
ultraviolet and infrared
visible light and radio waves
gamma rays and x-rays
visible light and radio waves
Pleiades is in the constellation...
Taurus
What is the primary advantage of the Hubble telescope over ground-based telescopes?
it's above the atmosphere
primary purpose of a telescope is...
to collect a large amount of light and bring it to a focus
The series of lines in the spectrum of hydrogen known as the Balmer series are seen in the visible portion of the spectrum and are characterized by electron transitions up from or down to the level n =
2
Capella is in the constellation...
Auriga
Antares is in the constellation...
Scorpio
If you view a hot spectrum through a cloud of gas, what sort of spectrum are you likely to see?
absorption spectrum
What problem are adaptive optics used to correct?
effects of atmospheric turbulence
what is a problem inherent to all radio telescopes?
poor angular resolution
The amount of light reflected by an object is its...
albedo
Which planets are the Jovian planets?
Jupiter, Saturn, Uranus, Neptune
Density =
mass/volume
do the terrestrial or jovian planets have higher densities?
terrestrial planets
What is the primary ingredient in Earth's atmosphere?
Nitrogen
The average rate of erosion on the Moon is far less than on Earth because...
The Moon lacks an atmosphere and free water
The splitting of spectral lines around sunspots is caused by...
the Zeeman effect
Ishtar Terra on Venus is a...
continental-sized plateau
A nearby star has a parallax of .2 arcseconds. What is its distance?
5 parsecs
The HR diagram plots...
luminosity vs. temperature
Which range of electromagnetic radiation is useful for observing new-born protostars within their gas and dust nebulae?
infrared
A typical solar type star spends most of its life...
as a main sequence star
What characteristic of a star cluster is used to determine its age?
main sequence turn-off
How far is the nearest star beyond the Sun?
between 1 and 2 pc away
What is not the same for each star in a cluster:
approximate age
mass
composition
distance from earth
relative heavy element abundance
mass
What is the single most important characteristic in determining the course of a star's evolution?
mass
A nearby star has a parallax of 0.5 arc seconds. What is its distance?
2 pc
What is the size of a typical white dwarf?
.01 solar radii
Which of the following stars has the greatest luminosity:
G5 III
B3 IV
G2 V
F7 Ia
M3 II
F7 Ia
Interstellar gas is composed mainly of...
hydrogen and helium
Some regions of the Milky Way appear dark because...
Stars in that direction are obscured by interstellar dust
Which two ingredients are needed to make an emission nebula?
Hot stars and interstellar gas
A cloud fragment too small to form a star becomes...
A brown dwarf
At what stage of evolution do T Tauri stars occur?
When a protostar is on the verge of becoming a main sequence star
What is the last observed stage in the evolution of a low-mass star?
white dwarf
What is one of the major differences between Cepheid variables and RR Lyrae variables?
Cepheids are higher luminosity stars than RR Lyrae variables
Currently the value of the Hubble constant is thought to be very close to...
70 km/s/Mpc
A one half solar mass protostar is just about to move onto the main sequence. This star will most likely have a main sequence spectral type of...
K
Who discovered the first object that eventually became known as a pulsar?
Jocelyn Bell
One of the consequences of the collision of two galaxies appears to be...
a burst of vigorous star birth
What does the Hubble Law measure?
The rate of expansion of the universe
From the Sun, what is the distance to the Galaxy's center?
26,000 ly
What is the classification given to a galaxy with a small nuclear bulge, and loosely wound arms starting from a bar through the nuclear bulge?
SBc
What type of variable star is used to determine the distances to globular clusters?
RR Lyrae stars
In the simplified version of Kepler's third law, P^2 = a^3, the units of the orbital period P and the semimajor axis of the ellipse a must be, respectively...
years and astronomical units
The vernal equinox is a point on the sky where the ecliptic intersects...
the celestial equator
On March 21, the right ascension of the Sun is...
0 hours
Aphrodite Terra and Ishtar Terra are on the planet...
Venus
The system of stellar magnitudes we currently use in astronomy was first used by...
Hipparchus
The vast majority of the first 100 extrasolar planets that have been discovered since 1995 are...
Jupiter size or larger and orbit close to their parent star
The resolving power of an individual radio telescope antenna is usually relatively poor because...
radio wavelengths are relatively large compared to the antenna aperture
Which are the terrestrial planets?
Mercury, Venus, Earth, Mars
A star with a complete spectral type of K5III would be called...
a giant
The precession of the Earth completes one cycle in a period of about...
26,000 years
Light travels through space at approximately...
186,000 km/sec
If the moon rises at sunset, its phase is...
full
The theories concerning the formation of the solar system indicate that the solar nebula had...
some initial angular momentum
What natural barrier tries to prevent two protons from combining?
electromagnetic repulsion
Which is not true of the giant planets vs. terrestrial planets? The giant planets:
are more massive
have longer rotation periods
have lower density
are considerably larger in volume
have longer rotation periods
The last planet visited by the Voyager 2 spacecraft in August 1989 was...
Neptune
The luminosity of a star is determined by its...
radius and temperature
The star Tau Ceti has an absolute magnitude of 5.68 and an apparent magnitude of 3.49. The distance to Tau Ceti is...
less than 10 parsecs
Which have the most rapid apparent motion in the sky:
planets
meteors
comets
asteroids
stars
meteors
What causes night and day?
The earth rotates on its axis
If we were to return tot he Moon and set up a permanent base at the Sea of Tranquility, how many times a year would the Earth rise and set?
Never; the earth would remain in the same position
In Provo, I see Polaris at about 40 degrees above the horizon. I go 10 degrees south in latitude. How high above the horizon will Polaris appear at my new location?
30 degrees above the horizon
When light from the concave primary mirror of a telescope is reflected by a small secondary mirror through a hole in the primary to its focus, this is called the...
Cassegrain focus
The word "planet" is derived from a Greek word meaning...
wanderer
The solar neutrino experiment designed by Raymond Davis has detected a rate of solar neutrinos arriving at the Earth which is...
about one third of the predicted rate