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162 Cards in this Set
- Front
- Back
The process of breaking light down into its component colors creates a/an |
spectrum. |
|
The prefix "kilo" added to a unit of measure (e.g., kilometers) means to |
multiply that unit of measure by 1000. |
|
An educated guess in science is known as a scientific |
hypothesis. |
|
The major source of information about bodies in the universe (outside of Earth) is through |
their light. |
|
A constellation shaped like the letter "W" in the northern sky is named |
Cassiopeia. |
|
The distance between any point on a wave and the next similar point is the |
wavelength. |
|
The positively charged particle contained within the core of an atom is the |
proton. |
|
Wein's Law is useful in astronomy to determine the |
temperature of a star. |
|
Spectroscopy is used in astronomy to |
determine composition, temperature, and the speed of a star towards or away from us. |
|
The visible spectral series (Balmer series) of the hydrogen atom spectrum is produced when electrons in hydrogen atoms transition from higher energy levels and end up on energy level labeled n = |
two. |
|
The Doppler effect can be used in astronomy to measure the |
speed of a star. |
|
A method for improving the images produced by ground-based optical telescopes despite blurring by the Earth*s atmosphere is called |
adaptive optics. |
|
The ability to distinguish between details or to distinguish two adjacent objects as separate is |
resolution. |
|
A radio telescope 100 meters across, when used to measure 10-centimeter waves, is |
1,000 wavelengths across. |
|
A curved lens or mirror can form an image by bringing light to a/an |
focus. |
|
The primary factor determining the resolution of an orbiting reflecting telescope is the |
diameter of the mirror compared with the wavelength of light being studied. |
|
Wet pavement seems darker than dry pavement at night because |
light from our headlights reflects through specular reflection into the eyes of oncoming drivers. |
|
A reflecting telescope of a given mirror diameter has several advantages over a refracting telescope with a lens of the same diameter. Some of these advantages include: |
Reflecting telescopes have no chromatic aberration and the mirror does not have to be perfectly clear glass like a lens does. |
|
An electronic device used to collect light and produce images in modern telescopes (instead of photographic film) is called a |
CCD. |
|
The most obvious difference between the images of planets and stars, as seen from the ground, is that stars |
twinkle. |
|
The annual path of the Sun through the sky, with respect to the stars, is the |
ecliptic. |
|
Many more people observe a lunar eclipse when it happens than would ever observe any solar eclipse because |
every person on the night side of Earth can observe a lunar eclipse, while a solar eclipse provides total darkness only along a narrow path on the surface of the earth. |
|
Suppose you are in California at 3 pm (local time) and you wish to look at the full Moon. The best idea would be to |
give up and try again later. |
|
Lunar eclipses do not occur with every full moon, nor do solar eclipses occur at every new moon, because |
the Moon and the Earth orbit the Sun in slightly different planes. |
|
A magnitude -1 star is about how much brighter than a magnitude +6 star? |
630 times. |
|
Christmas falls during the summer in Australia because |
the month of December is during summer in the southern hemisphere. |
|
Which of the following people important to the development of astronomy is given credit for the idea that the Earth is not the center of the solar system? |
Copernicus. |
|
A satellite orbiting just above the surface of the Earth orbits in about 1.5 hours, then at about how many Earth radii from the Earth's center must a satellite orbit to have a period of 24 hours? |
6.4. |
|
The Sun is positioned at one focus of the orbits of each of the planets in our solar system. What object is positioned at the other focus of these elliptical orbits? |
Nothing. |
|
If the size of an orbit of a planet around the Sun (i.e., its semimajor axis) is increased by a factor of four times, how will the period it takes the planet to orbit the Sun change? |
It will increase by eight times. |
|
Which of the following observational discoveries was made and reported by Galileo? |
Jupiter's four largest moons, the phases of Venus, craters and mountains on the Moon's surface, and a large number of stars in the Milky Way. |
|
Kepler's Second Law (also known as the Law of Equal Areas) implies that |
planets orbiting our Sun move faster when they are closer to the Sun. |
|
The heat energy in the Earth's interior is due to |
natural radioactivity. |
|
Of the inner planets, which has the strongest magnetic field? |
Earth. |
|
The hypothesis that the Moon formed from a ring of material ejected from the Earth by a collision is the |
ejection of gaseous ring model. |
|
Compared with Earth's atmosphere, Venus' atmosphere has a very high concentration of |
carbon dioxide. |
|
High-resolution images from Mars Global Surveyor show layered features and gullies that appear to be |
due to water flow. |
|
Why does Mars appear reddish-orange from Earth? |
Its rocks have suffered 'rusting' and contain reddish-orange iron oxides. |
|
Which of the following statements about the Earth-Moon system is true? |
The orbital period of the Moon around the Earth and the rotation period of the Moon around its axis are equal. |
|
Astronomers have observed that the Moon is more heavily cratered than the Earth. This is primarily because |
the Moon experiences almost no erosion compared to the Earth, causing craters to remain much longer. |
|
Many scientists now believe that liquid water flowed on Mars at some time in the past because of |
spacecraft rovers' observations of parallel laminations in rocks, spacecraft rovers' observations of spherical beads of hematite, spacecraft rovers' spectrometric evidence of jarosite, orbiting spacecraft observations of fans and deltas in the sand, and spacecraft measurements of water ice in the polar regions. |
|
Which of these phenomena are believed to be associated with Earth's magnetosphere? |
The Van Allen radiation belts and aurorae. |
|
Violently volcanic, with perhaps the youngest surface in the solar system is the satellite |
Io. |
|
Compared with the other giant planets, Uranus is evidently unique in having no |
internal heat source. |
|
Neptune's characteristic color is caused by absorption by atmospheric |
methane. |
|
The low average densities of Jupiter and Saturn compared with the density of Earth suggest that |
they contain large quantities of light elements, such as hydrogen and helium. |
|
The planet that rotates 'on its side' as it revolves around the Sun is |
Uranus. |
|
The Roche limit of a planet is the |
distance from the planet outside which gas and dust could coalesce without being torn apart by tidal forces from the planet. |
|
Although supposedly discovered in 1846 after computing the location of an unknown planet that was perturbing the orbit of Uranus, it is likely that Neptune was actually observed by |
Galileo Galilei. |
|
Because of conditions on Titan, the role water plays on Earth may be played by liquid |
ethane. |
|
The name of the space probe that arrived at Saturn in 2004, and has been making scientific observations of Saturn and its moons since then is named |
Cassini. |
|
Which of the following is NOT a possible description of Pluto? |
A brown dwarf. |
|
The largest component of a comet is its |
tail. |
|
Most of the extrasolar planets detected since 1995 are unlikely to harbor life as we know it because |
they are gas giants, without solid surfaces. |
|
Modern theories of solar system formation posit that planets formed through aggregation of many smaller bodies, each perhaps only hundreds of kilometers in size, called |
planetisimals. |
|
Using ground-based telescopes, most massive exoplanets orbiting other stars have been found by |
looking for a periodic Doppler shift in the star's spectrum as a massive planet causes the star to "wobble" slightly. |
|
Jupiter's chemical composition is most similar to that of |
the Sun. |
|
The giant (jovian) planets are large compared with the terrestrial planets because the giant planets |
obtained and retained more gas and ice because of their large distance from the Sun. |
|
Most known comets do not reappear in our sky very often because |
the orbits of comets are highly eccentric and their semimajor axes are large. |
|
The major piece of evidence that Pluto has an atmosphere has been obtained from |
measuring the gradual decrease, then increase in the light of a known star as Pluto passed in front of (occulted) that star. |
|
The light we receive from the Sun comes from the layer of the Sun's atmosphere called the |
photosphere. |
|
The solar corona is so hot it emits mainly |
x-rays. |
|
As the solar atmosphere expands outward into interplanetary space it becomes the |
solar wind. |
|
Areas of the Sun appearing relatively dark when seen in white light are |
sunspots. |
|
The orientation of the Sun's magnetic field changes, repeating a full cycle about every |
22 years. |
|
Which of the following is NOT influenced by the Sun's magnetic field? |
The Sun's blackbody spectrum. |
|
Solar filaments that project into space at the Sun's visible edge are called |
a prominence. |
|
Of the regions of the Sun listed below, which has the highest temperature? |
The core. |
|
Einstein's General Theory of Relativity published in 1916 was verified through which solar event in 1919? |
Total solar eclipse. |
|
Categories of stars based on their respective spectra are called |
spectral types. |
|
The angle at which a star appears to move when observed from the ends of a baseline of 1 A.U. is the star's |
parallax. |
|
A star that is 40 parsecs from the Sun, if moved to a distance of 10 parsecs, would be |
16 times brighter. |
|
A temperature-luminosity diagram of stars usually includes a diagonal band called the |
main sequence. |
|
Star Albert appears to have the same brightness through red and blue filters. Star Bohr appears brighter in the red than in the blue. Star Curie appears brighter in the blue than in the red. Which of the following orderings of these stars has them ordered from coolest to hottest? |
Bohr, Albert, Curie |
|
One can determine the radius of a nearby star (that is not necessarily on the main sequence) knowing only its |
apparent brightness, parallax, and surface temperature. |
|
The Doppler shift of a star depends only on the star's |
radial velocity. |
|
Cepheid variables are useful to astronomers for measuring distance to other galaxies because |
the period of their variation in brightness is correlated to their average intrinsic luminosity. |
|
A way of determining that a globular cluster is old is by charting the population of stars on a temperature-luminosity diagram and noticing that |
the massive, hot stars are missing from the chart. |
|
A stellar sized hot body that derives its energy from free-falling gravitational collapse is a |
protostar. |
|
The fusion process which produces energy in most stars forms helium from the nuclei of |
hydrogen. |
|
The number of neutrons in a neutral atom of 614C is (atomic number=6; atomic mass=14) |
8. |
|
The process of building heavier atoms from lighter ones is called |
nucleosynthesis. |
|
As a protostar is formed from a cloud of gas and becomes a pre-main-sequence star, which one of the following events does NOT occur? |
The protons in the gas begins to fuse. |
|
The amount of energy released in a nuclear fusion reaction is directly proportional to the |
mass difference between the initial reactants and final products. |
|
Brown dwarfs emit electromagnetic radiation primarily as which of the following types of light? |
Infrared radiation. |
|
The so-called neutrino problem of the 1980s and 90s was concerned with |
detection of only about one-third as many neutrinos from the Sun as were expected. |
|
After a star enters its red giant phase its core will heat up enough for the triple-alpha process to begin to produce |
carbon. |
|
When a star becomes unstable, it may eject shells of gas into space forming a/an |
planetary nebula. |
|
Stars retaining less than 1.4 solar masses after their unstable phase will become |
white dwarfs. |
|
Oscillating stars were ruled out as an explanation for pulsars because they would not have the correct |
period. |
|
If, after a Type II supernova, the stellar core is less than 2 solar masses, the result will probably be a |
neutron star. |
|
The Chandrasekhar limit is the |
theoretical maximum mass which a white dwarf can have without exploding as a nova. |
|
High-energy charged particles believed to be produced most of the time by supernovae are called |
cosmic rays. |
|
Which of the following statements about pulsars is true? |
Pulsars cannot be rotating white dwarfs because their rotation rate is so high that a white dwarf would be ripped apart. |
|
When a main-sequence star runs out of hydrogen fuel in its core, |
the core contracts and thus heats up. |
|
If, after a supernova, the stellar core retains more than 2 or 3 solar masses, the result will be a |
black hole. |
|
The spherical surface around a collapsed star in which light can orbit is the |
photon sphere. |
|
The presence of a black hole in a galaxy core can be inferred from |
the velocities of stars near the core. |
|
What three quantities completely define the physical characteristics of a black hole? These characteristics can be used to discriminate one black hole from another black hole. |
Mass, spin rate, and electric charge. |
|
Gamma-ray bursts have been found to be have sources |
in galaxies billions of light years away. |
|
If a massive star (more than ten times the mass of the Sun) should form a black hole, a companion star that had been orbiting this now black-hole-star at a distance of one light-year would |
continue to orbit in its original orbit. |
|
Astronomers believe that when our Sun becomes a black hole far into the future |
Wait! Our Sun is too small to ever form a black hole. |
|
Which one of the following observations is one of the pieces of evidence used by astronomers to detect an object that could potentially be a black hole? |
Flickering x-rays from an accretion disk around the black hole. |
|
A cloud of dust and gas that scatters the light of nearby stars is a/an |
reflection nebula. |
|
The symbol H II would denote a hydrogen atom with a charge of |
+1. |
|
The large (60,000 light-year radius) sphere of older stars and globular clusters around the central region of the Galaxy is the |
halo. |
|
The "spiral arms" of the Galaxy are embedded in the |
disk. |
|
To trace out the spiral structure of our Galaxy we should look at |
very young objects. |
|
The spectral line that has a wavelength of 21 cm is believed to be produced by |
hydrogen. |
|
The astronomer who is credited with first arguing in 1917 that Earth is not at the center of our galaxy is |
Harlow Shapley. |
|
Which one of the following statements about our Milky Way Galaxy is FALSE? |
Globular star clusters reside in the halo, and contain main-sequence stars spanning all spectral types, from O through M. |
|
What were originally called spiral nebulae are now more accurately called |
spiral galaxies |
|
Galaxies are classified according to their |
shape. |
|
In 1929, Hubble announced that a galaxy's distance from us is directly proportional to its |
redshift. |
|
Which of the following are primary distance indicators? |
Cepheid variables. |
|
The discovery that some clusters of galaxies do not have enough visible mass to maintain the structure of the cluster has become known as |
the missing mass problem. |
|
Why is it not surprising that very little star formation is found in elliptical galaxies? |
Elliptical galaxies tend to consist mostly of old stars and have very little free gas and dust. |
|
Astronomers cannot determine the distance to other galaxies using the geometric method of parallax as we do for some stars because |
galaxies are so far away that any parallax angle would be far too small to measure. |
|
The Milky Way Galaxy is a type of galaxy called |
spiral. |
|
Many astronomers believe that most of the dark matter of the universe does not consist of "normal" matter made of protons, neutrons, and electrons, but probably consists of |
WIMPs. |
|
The principle relating the distance of a galaxy and its measured recessional speed is known as |
Hubble's Law. |
|
Astronomers discovered quasars while trying to correlate optical objects in the sky with |
radio sources. |
|
The word "quasar" came from the acronym that was used to identify a |
quasi-stellar radio source. |
|
By current consensus, quasars have at their centers large |
black holes. |
|
The multiple images seen in a gravitationally lensed quasar have all but which of the following? |
The same light path through space. |
|
Galaxies that radiate strongly at radio and x-ray wavelengths are called |
active galaxies. |
|
How does a QSO differ from a QSR? |
QSO's do not produce much radio frequency radiation, while QSR's produce much radio radiation. |
|
The spectra of quasars differs from that of normal stars in that it |
is greatly red-shifted. |
|
Quasars are probably powered by |
material falling into a central supermassive black hole. |
|
Which of the following statements about quasars is true? |
Quasars probably faded with time, and have now evolved into relatively normal galaxies. |
|
The "fuzz" seen around some quasars is evidence for which of the following surrounding the quasar? |
Galaxy. |
|
"Why is the sky dark at night" is an age-old question generally remembered as |
Olber's paradox. |
|
The assumption that the Universe is homogeneous and isotropic is called |
the cosmological principle. |
|
The notion that the Universe had an instant when it began is implied by its |
expansion. |
|
If the expansion of the Universe will eventually stop and reverse, then the Universe is said to be |
closed. |
|
A Universe in which composition and density are the same everywhere at a given time is |
homogeneous. |
|
What kind of universe has a density greater than the critical density? |
Closed. |
|
The cosmological principle states that the universe is assumed to be |
isotropic and homogeneous. |
|
The standard candles that were used to measure distances to other galaxies which led to the discovery of what is now called "dark energy" were |
Type Ia supernovae. |
|
A time far in the future of the Universe, when the density of photons and elementary particles will be very low is known as |
the dark era. |
|
Many astronomers now believe that the expansion of the universe is accelerating, driven by the repulsive effect of the cosmological constant, perhaps caused by something known as |
dark energy. |
|
The force holding the nuclei of atoms together is the |
strong force. |
|
A universe that has not expanded uniformly, but for some very short period in its history expanded rapidly, is called |
inflationary. |
|
Quasars and the cosmic background radiation are the strongest evidence against the |
steady-state theory. |
|
The relative abundances of protons and neutrons was set when the age of the Universe was about |
1s. |
|
One success of the inflationary theory of the Universe is that it can explain why the Universe appears to be |
flat. |
|
The lightest elements (H, He, and Li) formed shortly after the big bang in a fusion process known as |
primordial nucleosynthesis. |
|
There are good reasons to believe that at one time the Universe expanded extremely rapidly. This "inflation" occurred primarily |
within the first 10-30 seconds after the Universe started expanding. |
|
Which of the following prevented photons from traveling long distances in the early Universe? |
Free electrons easily interacted with the photons, scattering them in many directions. |
|
Most scientists now believe that protons and neutrons are not fundamental particles, but consist of small particles called |
quarks. |
|
The hypothesis that other universes (potentially with different physical laws and constants) exist is known as the |
multiverse hypothesis. |
|
In the 1950s scientists at the University of Chicago synthesized complex organic molecules by passing sparks through a mixture of |
water vapor, methane, and ammonia. |
|
The planetary satellite that is thought to have below its surface the liquid water necessary for life as we know it is |
Europa. |
|
The organic molecules that have been found in some meteorites are |
amino acids. |
|
A well-known effort to find intelligent life elsewhere in the Universe is or was called |
SETI. |
|
What is meant by the term "organic compound"? |
A chemical compound containing carbon. |
|
The name given to one equation estimating the probability of life in the Galaxy is the |
Drake equation. |
|
Why do most astronomers dismiss the notion that UFOs indicate that Earth has been visited by extraterrestrial beings? |
Because of the great distances involved in any intelligent beings travelling to Earth when nothing can travel faster than the speed of light. |
|
Around which of the following objects is there thought to be the best chance of finding life outside the solar system? |
A main-sequence F-type star. |
|
Searches for signals from intelligent extraterrestrial life have been conducted mainly at |
radio wavelengths. |
|
According to William Dembski, most people identify designed objects through their |
complexity and specificity. |
|
The ability to distinguish between details or to distinguish two adjacent objects as separate is |
resolution. |