Final Exam
Based on many surveys of the average density of matter in the universe (regular matter and dark matter), astronomers now conclude that the average density of the universe is a. less than the critical density b. exactly equal to the critical density c. more than the critical density d. essentially equal to zero e. so great that the universe will experience a "big crunch" before the Sun becomes a red giant
a
Galaxies that we see as they were 11 billion years ago or more, as compared to galaxies today, are generally: a. bluer and smaller b. redder and smaller c. redder and larger d. bluer and larger e. pretty much the same
a
If you wanted to find a type of atom in your little finger that has been in its present form (been the same element) since the beginning of the universe, which element should you look for? a. hydrogen b. carbon c. iron d. oxygen e. Einsteinium
a
If you wanted to write a complete "cosmic address" for yourself, including every location or structure you live in, which of the following would NOT be part of that address? a. the Coma Cluster b. the Milky Way Galaxy c. the Local Group d. the Solar System e. planet Earth
a
Photosynthesis, once it was planet-wide, changed the atmosphere of the Earth by introducing a significant amount of a. oxygen b. carbon dioxide c. methane d. ammonia e. vibranium
a
Scientists looking at an overview of physics today understand that there are four forces that govern all action in the universe. These four forces are the strong nuclear force, the weak nuclear force, electro-magnetism and a. gravity b. dark matter c. fusion d. inflation e. the force that Luke learned to use in Star Wars
a
The first satellite (spacecraft with instruments) to measure and confirm the cosmic microwave background was the: a. COBE (COsmic Background Explorer) b. Hubble Space Telescope c. Einstein d. Voyager 1 e. Chandra
a
The first scientist to propose a specific model (the primeval atom model) for the big bang was a. Lemaitre b. Hubble c. Sandage d. Peebles e. Nobel
a
The satellite that has given us the most precise measurements of the characteristics of the cosmic background radiation is: a. Planck b. Einstein c. the Hubble Space Telescope d. BeppoSAX e. Io
a
What does the Fermi Paradox say? a. Given all the time since the Big Bang and all the stars, why has some form of intelligent life in the Galaxy not established a network throughout the Galaxy and visited us? b. Given the size of the Galaxy, there should be an exact duplicate of the Earth somewhere and we should have found it c. If life on Earth took a miracle to form, then there should be no life anywhere else d. If all the planets in our solar system besides Earth are lifeless, then it must follow that most of the planets around other stars are also lifeless and finding life is hopeless e. When Fermi got ill, he always needed two doctors to diagnose him
a
When we determine the age of the universe using the Hubble Time, what important simplifying assumption goes into our calculations? a. that the expansion of the universe has been happening at the same rate - neither speeding up or slowing down b. that all the galaxies are moving away from us at exactly the same speed, no matter how far away they are c. that the cosmological principle doesn't hold: the universe is not isotropic and homogeneous d. that we have accounted correctly for the effects of dark energy e. that the universe is actually contracting instead of expanding
a
Which of the following can we NOT learn from studying the Doppler shifts in the spectrum of galaxies beyond our Local Group? a. whether they have Jupiter-mass planets around many of their stars b. their red shifts c. their rotation speeds d. their masses e. their distances
a
Which of the following is a good summary of what most astronomers think about UFO reports in the popular media? a. so far there is no scientific evidence that UFO's have anything to do with life outside the Earth b. it is now clearly established that alien spacecraft have crashed on Earth; we have the bodies of the aliens who flew them here c. while no UFO's have landed, we have overheard communications between them with our radio surveys and thus have evidence that there are intelligent creatures aboard them d. UFO's are now known to come from the planet Mars, the only other planet that we know has life on it e. UFO's have kidnapped a number of Earth inhabitants, including at least one well-known astronomer; her reports convinced other scientists that UFO's are indeed alien spaceships
a
Which of the following statements about our modern ideas of how spiral galaxies form and develop is TRUE? a. the central bulges of spiral galaxies formed first and their disks formed later b. star formation in the spiral galaxies is much higher today than it was 8 billion years ago c. spiral galaxies formed pretty quickly after the Big Bang and already looked then the way they look today d. spiral galaxies have evolved until today they are all "red and dead", containing just old stars and showing almost no current star formation e. spiral galaxies cannot have a central super-massive black hole, so astronomers don't understand just how they formed
a
According to our modern "bottom-up" model of the formation of large structures in the universe, the structures that formed first were about the mass of a a. star b. large globular cluster or a small galaxy c. giant elliptical galaxy d. supercluster of galaxies e. an ice-cold mug of root beer
b
Astronomers believe that the large elliptical galaxies formed a. right after the Big Bang, looking just like they look today b. from the collision and merger of many smaller fragments c. only recently, less than a billion years ago (before that galaxies were spirals) d. without the presence of any super-massive black holes e. without any involvement of dark matter (just from matter we can detect)
b
Astronomers have discovered a planet orbiting Proxima Centauri, the star closest to the Sun. This is a star of spectral type M, with 12% the mass of the Sun and 15% the size of the Sun. The habitable zone around this star would be a. much larger (wider) than the Sun's b. much closer to the star than the Sun's c. in about the same place as the Sun's asteroid belt d. much more narrow (small) than the diameter of any planet e. the source of all the UFO's that have been reported by UFO believers on Earth
b
Astronomers have measured that there is more helium in the universe than can be explained by the fusion in stars over the last 13 billion years. How do they think the extra helium got into the universe? a. the extra helium was produced in the accretion disks of supermassive black holes b. the extra helium was made during the first few minutes of the Big Bang, when the entire universe was hot enough for fusion to occur briefly c. the extra helium was produced by the interaction of dark matter with the material at the edges of all galaxies d. the extra helium was produced recently during Type Ia supernova explosions e. the idea that there is extra helium has been shown to be in error; we were confused by the high red shifts of distant galaxies distorting their spectra
b
Chemically, the process leading to life on Earth began with lots of liquid water and a. helium b. hydrocarbons (molecules which had hydrogen and carbon) c. radium and its isotopes d. molecules containing iron e. molecules containing iridium
b
How do astronomers know that there aren't significant amounts of dark matter within our solar system? a. so much dark matter would affect the amount of energy coming out of the Sun, and we see no evidence for that b. a lot of dark matter would affect the motions (orbits) of our spacecraft as the move through the solar system, and see no such effect c. the theory of dark matter, which now explains everything we want to know about it, tells us that it can only exist on the outside of galaxies d. such dark matter would affect the weather patterns on Earth, and we see no such effect e. astronomers have now discovered quite a bit of dark matter in the solar system, so the premise of the question is wrong
b
How does a period of extremely fast inflation very early in the history of the universe explain the observation that the geometry of the universe looks flat (not curved) to us? a. during inflation a lot of the mass drained out of the universe, leaving its gravity much weaker b. inflation increased the size of the universe so much that the resulting universe looks flat from any point of view c. inflation led to the production of so much dark matter that the universe got pulled into the shape of a black hole d. inflation caused the temperature of different parts of the universe that can't see each other still be the same e. The universe is actually highly curved and not flat
b
If a very distant galaxy looks blue overall to astronomers, from this they can conclude that: a. the galaxy is moving toward us at great speed b. the galaxy must have a lot of young stars and thus active star formation must still be going in it c. the galaxy must be composed mostly of very old stars d. the galaxy must not be especially massive when compared to most galaxies e. the galaxy must have had a personal tragedy of some sort and needs a lot of love
b
If we include the effects of deceleration in our calculations of the age of the universe, the age we get is: a. greater than the Hubble time b. less than the Hubble time c. equal to the Hubble time d. either greater or less depending on the amount of deceleration e. you can't fool me; this question cannot be answered without knowing the exact value of the Hubble constant.
b
In our modern view of the expansion of the universe, we understand that it is space that is stretching; individual galaxies don't speed away from each other as if they were rockets. In that case, why do galaxies show a red-shift? a. as galaxies age, they get redder and redder b. as space stretches, the waves of radiation in space also stretch and their wavelength increases c. as space stretches, the presence of dark matter slows down the light between galaxies d. as time goes on, waves in space encounter more and more dust, and get redder e. astronomers cannot think of any good explanation for the red-shift if it's space that expands/stretches
b
In the early 1950's, Stanley Miller and Harold Urey conducted a series of pioneering laboratory experiments involving simulations of the early Earth. What did these experiments reveal? a. that the early Earth was constantly bombarded by asteroids and comets b. that under the conditions on the early Earth, they could synthesize some of the building blocks of life in a laboratory c. that the early Earth was much hotter than anyone had suspected d. that the early Earth had received microscopic life in meteorites that had come from Mars in the very beginning of the solar system's history e. that the early Earth had to have been covered with a thick layer of ice, just like Jupiter's satellite Europa
b
One place that astronomers think might have had life start long ago is Mars. Which of the following is not a discovery that we have made on Mars so far? a. observing what looks like dried up river channels from orbiting spacecraft b. the discovery of organic materials (the chemical building blocks of life, such as amino acids) by spacecraft that have landed c. the discovery that Mars long ago had plenty of flowing water, from the composition and layering of some of the rocks examined by Mars rovers d. the discovery of mudstone on Mars, which indicates that ancient Mars may have been more habitable than Mars today e. the discovery of significant amounts of frozen water on Mars, under the surface
b
Photosynthesis releases a particular gas as a byproduct. This gas is: a. carbon dioxide b. oxygen c. water vapor d. methane e. DNA
b
Recent observations indicate that the universe is expanding faster today than it was a few billion years ago (that, in other words, the expansion of the universe is accelerating.) What kind of observations have led astronomers to this surprising conclusion? a. the measurements of cepheid variables in the galaxies of the Local Group b. the measurement of galaxy distances using Type Ia supernovae c. the discovery of large amounts of dark matter in the halo of the Milky Way d. the measurements of the amount of deuterium in the universe e. the fact that galaxies today are getting a lot more speeding tickets than they used to
b
There is some irony in the fact that the Hubble Space Telescope has shown that Edwin Hubble's classification scheme for galaxy shapes only works in the later stages of the universe. What have really deep pictures (going way back in time) taken with the Hubble Telescope shown about galaxies long ago (in the first few billion years after the Big Bang)? a. long ago, all the galaxies were spiral shaped; there were no other shapes at all b. long ago, galaxy shapes were not (for the most part) regular and organized; galaxies looks chaotic and lumpy c. long ago, there were no galaxies at all; stars were evenly distributed through space and had not yet formed galaxies d. long ago, galaxies were much larger than galaxies are today; those very large galaxies broke apart and made the galaxies we know e. you can't fool me; the Hubble Space Telescope has a smaller mirror than the largest telescopes on the ground. We can't use it to see galaxies that long ago.
b
Today, we believe that only a small number of elements were actually formed during the Big Bang. Which of the following was NOT one of these: a. hydrogen b. carbon c. lithium d. helium e. you can't fool me, all of the above were definitely formed during the big bang
b
When astronomers have examined rich clusters of galaxies with their instruments, they have found that these clusters a. contain far more spiral galaxies in their central regions than elliptical galaxies b. are more likely to contain giant elliptical galaxies than poor clusters c. are the only places in the universe where galaxies find a way NOT to collide d. contain mostly galaxies dominated by the light of young stars (stars formed recently) e. are so big that there is a lot more space between the galaxies than in poor clusters like our Local Group
b
When astronomers say that the groups of galaxies are distributed isotropically, they mean that a. all the galaxies are about the same size b. the way galaxies are arranged in space looks the same in all directions c. galaxies all have interstellar matter at the same temperature d. galaxies all have the same age e. galaxies all contain the same isotopes of elements
b
Which of the following is a biomarker that could be used from an observatory around a nearby star, with the right equipment, to identify the Earth as a planet with life: a. the presence of a large moon around the Earth b. free oxygen in the Earth's atmosphere c. the abundance of micro-organisms in the deserts of the Earth d. the fact that most of our atmosphere is made of nitrogen e. ice in the Earth's polar caps
b
Which of the following is a way that having an active galactic nucleus (AGN), with a supermassive black hole in the center, can affect the development of a galaxy? a. it can seriously reduce the total mass of the galaxy when lots of stars fall into the black hole b. huge energetic jets from the accretion disk can disturb and lessen star formation in the galaxy c. it can break apart the galaxy into several smaller galaxies d. it can cut off all electro-magnetic radiation from most of the galaxy, except for the visible light from the outermost stars e. sorry, I don't buy it; the black hole at the center is so small, there is simply no way that astronomers can think of that it could affect the development of the whole galaxy
b
Which of the following is, to the best of our knowledge, in the habitable zone of its star: a. a "hot Jupiter" taking 4 days to orbit a G-type main sequence star b. a planet about 1.05 AU from a G-type main sequence star c. a Jupiter-mass planet taking 15 years to orbit a K-type main sequence star d. a planet in an orbit the size of the Earth's around a red giant star e. all of the above
b
Why did Einstein introduce the cosmological constant into the equations of his General Theory of Relativity when describing the universe? a. Einstein did not realize that black holes would exist at the centers of galaxies and pull everything into them b. Einstein's equations required the universe to expand or contract; he could not imagine or accept it doing either one, so he put a factor in to stop it from moving c. Einstein talked to Hubble and learned about Hubble's observations of the expanding universe, which made him so uncomfortable that he decided to change his equations d. Einstein had a hunch that the universe was accelerating (speeding up its expansion) back in 1918 and so introduced the constant into his equations to describe that e. Einstein liked cups of tea in the afternoon, and his constant was a comment on that habit
b
According to our current understanding, giant elliptical galaxies form: a. by being located near the center of the Big Bang explosion and thus getting a major early push b. only in the giant voids that astronomers are discovering among the filaments and chains of galaxies c. by the merger (or swallowing) of a number of smaller galaxies in a cluster of galaxies d. when a black hole swallows enough material so that most of the stars in the galaxy are inside the black hole, leaving only a thin halo e. by watching too much football and drinking too much beer
c
According to the Cosmological Principle, the universe a. has no beginning and no end b. cannot be understood by the use of scientific observations alone c. is isotropic and homogeneous d. consists only of galaxies that are exactly like the Milky Way e. has all the galaxies arranged in groups about the size of our Local Group
c
According to the most recent data from satellites making precise measurements of the properties of the cosmic background radiation (CBR), a. normal matter (like the atoms in our bodies) makes up 99% of the total mass-energy of the universe b. dark matter makes up less than 5% of the total mass-energy of the universe; it's only a minor contributor to what makes up the cosmos c. the dark energy makes up just a little less than 70% of the density of the universe, making it the most significant constituent of the mass-energy d. normal matter, dark matter, and dark energy each contribute about 1/3 of the total density of the universe - their contributions are almost exactly equal e. the universe is only about 6,000 years old
c
After the Big Bang, in order for the universe to become transparent to light and other electro-magnetic radiation, what had to happen? a. stars and galaxies had to form b. the whole universe had to be hotter than the interior of a star c. the density of the universe had to decrease (to 1000 nuclei per cubic centimeter or less) d. the dark energy had to dominate over regular matter and energy e. telescopes had to be invented
c
An astronomer discovers a massive galaxy which has four nuclei. What is a likely explanation for a galaxy having more than one nucleus? a. the nuclei of galaxies often split into two or more parts because of internal activity b. the galaxy must have been a quasar earlier in its life c. the galaxy must have swallowed several smaller galaxies that were its neighbors d. the galaxy must have had an unusual number of supernova explosions e. astronomers have no explanation for multiple nuclei in galaxies; it's baffling
c
An astronomer is observing a distant galaxy which looks blue. Which of the following can she conclude from this observation? a. the galaxy must be moving toward us (must have a blue shift) b. the galaxy must be extremely large (probably a giant elliptical) c. the galaxy must have a lot of star formation going on at the time we are seeing it d. the galaxy must be rotating very slowly or not at all e. the galaxy must contain only older stars (those that formed billions of years ago)
c
At first, right after the Big Bang, the universe was too hot for nuclei and electrons to combine into the kinds of neutral atoms that are familiar to us today. How soon after the beginning did it become cool enough for neutral atoms to form? a. 10-43 seconds b. 3 minutes c. a few hundred thousand years d. a billion years e. only last Thursday
c
For the complex biochemical reactions of life (as we know it) to happen, a solvent is required. What is that solvent for life on Earth? a. ammonia b. methane c. water d. carbon dioxide e. diet Coke or diet Pepsi
c
How do astronomers currently think the amount of detectable (observable) matter in the universe compares to the amount of dark matter and dark energy? a. the amount of detectable matter is about equal to the amount of dark matter & energy b. the amount of detectable matter is far greater than the amount of dark matter & energy c. the amount of detectable matter is far less than the amount of dark matter & energy d. the amount of detectable matter is about 1/10th the amount of dark matter & energy e. there is no evidence for dark matter anywhere, so this is not a topic astronomers can make any estimates about
c
If alien beings found one of the Voyager spacecraft in a million years, what would they find aboard? a. a container with a concentrated sample of the most common Earth bacteria b. a flag from the Soviet Union c. an audio and video record d. a human skull done in bronze e. a video tape with every episode of the original "Star Trek" TV series
c
In describing the universe using his equations of general relativity, Einstein assumed that it was isotropic (the same in all directions.) What recent observations have confirmed that the universe is isotropic on the large scale? a. the discovery of pulsars b. the discovery of cannibal galaxies c. measurements of the 3-degree cosmic background radiation d. measurements of neutrinos from Supernova 1987A e. the discovery that there is really nothing very good on TV, no matter which way you point your dish (antenna)
c
In which of the following domains of the universe have astronomers NOT found evidence for the presence of dark matter today? a. the Milky Way Galaxy b. other spiral galaxies c. the solar system d. clusters of galaxies e. superclusters of galaxies
c
One of the things that our current "standard model" of the Big Bang Theory doesn't explain is a. why the universe is expanding b. why there is a cosmic microwave background filling all of space c. why the temperature of the cosmic microwave background is so uniform throughout all of space d. why there is more helium in the universe than stars could have produced in 13.8 billion years e. why the galaxies show a red shift
c
One reason that some scientists think that there may be life under the ice-crust of Jupiter's moon Europa is that: a. Europa is unusually warm on its surface; in some places the climate resembles Hawaii on Earth. b. Life has already been found on Io, Jupiter's inner-most large moon c. Life has been found on Earth, at the bottom of the ocean, deriving its energy not from sun-light but from hot mineral-laden vents coming from deeper inside our planet; something similar could happen at the bottom of the ocean on Europa d. meteorites blasted off Europa have been found on Earth and we detect the building blocks of life inside these meteorites from Europa e. we are receiving intriguing radio messages from Europa that indicate some form of intelligence lives there
c
Scientists think that the life we have on Earth today originated some time between 3.5 and 3.8 billion years ago. Yet the solar system and the Earth are known to be at least 4.5 billion years old. Which of the following is one reason life as we know it had to wait until 3.5 to 3.8 billion years ago to get going? a. supernovae were exploding near the Sun's location every year back then b. the Sun was so much cooler when the Earth formed, that the Earth's oceans (and even Mars' oceans) were frozen over for billions of years c. before 3.8 billion years ago, the Earth was experiencing a period of heavy bombardment, when giant chunks of rock and ice left over from planet formation kept hitting our planet and making it uninhabitable d. experiments like the one done by Miller and Urey show that life on Earth could not form until plants produced a lot of oxygen for our atmosphere e. the early solar system was filled with dark matter, and life could not form with so much dark matter around
c
Some astronomers searching for what the mysterious "dark matter" might be made of have pinned their hopes on MACHO's (MAssive Compact Halo Objects). What do they think these MACHO's are? a. huge concentrations of antimatter, outside of galaxies b. vast clouds of neutrinos, emitted by ancient supernovae c. black holes, brown dwarfs, and white dwarfs in the regions outside the main disk of our Galaxy d. "cannibal galaxies" that have swallowed smaller galaxy neighbors until they have grown very large e. large groups of college football players who have flunked astronomy, and now hang around the outskirts of town, just showing off their muscles
c
Some scientists speculate that our universe is not the only universe that exists, but the only one we can gather evidence about. This idea is called a. the Big Bang theory b. the cosmological principle c. the multiverse theory d. Hubble's Law e. the accretion disk hypothesis
c
The cosmological principle in astronomy a. is only an assumption, for which we don't have any real evidence yet b. applies only to the Milky Way Galaxy, not to anything outside it c. is confirmed by many observations done by Hubble and many other astronomers since d. is contradicted by the existence of quasars e. is an old Greek idea, now completely discredited by modern observations
c
The reciprocal of the Hubble constant (1/H) is a rough measure of the: a. the period of a typical Cepheid variable b. the distance to the last galaxies that formed c. the age of the universe d. the luminosity of a type I supernova explosion e. the cost of building a telescope in space
c
The rich galaxy cluster that is closest to our Local Group of galaxies is the a. Coma Cluster b. Hercules Cluster c. Virgo Cluster d. Ursa Major Cluster e. Peanut Cluster
c
Think for a moment about an atom of the element lead (atomic number 82) inside the radio that you listen to in the morning. In which of the following places has this atom probably NOT been during the course of its existence? a. a previous generation star b. a supernova explosion c. the Sun d. a cloud of gas and dust which would clump to become a star and a family of planets e. the Earth's crust
c
To map out how clusters of galaxies are distributed in the universe, astronomers needed to know where each cluster was in the sky AND a. how many galaxies were in each cluster b. how blue or red the galaxies in each cluster were c. how far away from us each cluster was d. whether any of the galaxies in each cluster acted like quasars e. whether any gravitational lensing could be seen in each cluster
c
When do astronomers now think that the "dark energy" began to accelerate the expansion of the universe? a. right after the Big Bang (after the first three minutes or so) b. a few million years after the Big Bang c. several billion years after the Big Bang d. about ten million years ago e. when the city of Bayonne, New Jersey was founded
c
Which of the following is a recent (last few decades) discovery that confirms the key idea of the Copernican Principle? a. that the Earth has a Moon b. that gravity waves exist c. that planets around other stars are common d. that 65 million years ago a large asteroid hit the Earth e. that people from Eastern Europe are pretty smart
c
Which of the following is the Earth not located in? a. the solar system b. the universe c. globular cluster M-13 d. the Milky Way Galaxy e. the Earth is located in all of the above
c
Which of the following spacecraft is NOT leaving the solar system? a. Voyager 1 b. Voyager 2 c. Galileo d. Pioneer 10 e. Pioneer 11
c
Which of the following statements about dark matter is FALSE: a. it is observed to be a major part of the Milky Way b. it is observed to be present in other groups of galaxies c. astronomers have a pretty good idea what the dark matter is made of d. we can detect its gravity, even though we can't see it e. it may make up even more of the universe that the matter we can see
c
Which of the following statements about the early universe (as envisioned by the standard model of cosmology) is FALSE? a. as the universe expands, its temperature decreases b. at the beginning, the temperature was hot enough to turn energy into matter c. at the very beginning, the energies were so great that the universe was actually contracting for a while d. at the beginning, the universe was not transparent to electro-magnetic radiation e. at the very beginning, anti-matter (as well as matter) was present in significant quantities
c
Why do galaxies collide, while stars almost never do? a. stars have a very strong negative charge on them, so they repel other stars that get near b. stars don't have very much mass, so their gravity is very small and can't pull things well c. stars are much further apart (compared to how big they are) than galaxies are d. stars are surrounded by planets, which prevent collisions; galaxies are not e. actually, stars collide all the time, but astronomers don't have any way of observing it
c
With enormous effort, a team of astronomers manages to collect enough light from a galaxy far, far away to produce a spectrum. That spectrum has lines from the elements carbon, silicon, and sulfur. This tells the team that a. the galaxy must be closer to us than 1 billion light years b. the galaxy must contain a quasar c. the galaxy must have had an entire generation of stars that was born, lived, and died d. the galaxy must be a massive elliptical galaxy e. what they are seeing is not a galaxy at all, but the remnant of one supernova
c
According to astronomers, which of the following places in the outer parts of our solar system might be a reasonable place for life to exist? a. in the core of the planet Saturn b. in the rings of Neptune c. in the mountains of Pluto d. under the ice of Jupiter's moon Europa e. on the surface of some of the smaller members of the Kuiper Belt
d
According to our modern theories, the geometry of the entire universe (all of space-time) may be curved or warped. This is a pretty bizarre notion; what other discovery in astronomy has helped us believe that space may be able to curve or warp? a. supernova explosions and the elements they produce b. how the light output of cepheid variables changes with time c. the existence of dwarf elliptical galaxies d. the properties of black holes e. the error in the shape of the mirror on the Hubble Space Telescope
d
According to our textbook, roughly what percent of the mass and energy contents of the universe is made up of dark matter plus dark energy? a. 5 percent b. 10 percent c. 50 percent d. 95 percent e. astronomers have no way of estimating this percentage
d
According to the models of the universe we discussed in this course, why do the galaxies move apart (why do we have Hubble's law)? a. gravity is a repulsive force, once you get outside the Milky Way Galaxy b. each galaxy has net charge on it, and they repel by the laws of electricity c. supernova explosions happen more frequently on one side of each galaxy, giving the entire galaxy a push that moves it away from its neighbors d. as a result of the Big Bang, space itself is stretching, and this stretching carries the galaxies away from each other e. strong political and religious disagreements among the galaxies
d
At about 1 second after the beginning of the universe, one type of particle was able to start traveling freely through the universe. These particles are still with us, but they are extremely hard to detect. They are called: a. photons b. protons c. electrons d. neutrinos e. college presidents
d
By examining rich clusters of galaxies, such as the Coma Clusters, astronomers have discovered that spiral galaxies a. grow to be very large and bright at the centers of these clusters b. turn out to be most of the galaxies in such clusters, and many are found throughout each cluster c. do not exist at all in such clusters d. are found mostly in the outer regions of such clusters, not in the middle e. are all tilted exactly the same way in such cluster; all their disks are fully aligned
d
Factoring in everything we currently know about the history of the universe, our best estimate for the age of the universe is a. 4.6 billion years b. about 100 billion years c. roughly 2 million years d. about 13.8 billion years e. the age of the universe is infinite; there was no beginning
d
From a scientific perspective, which of the following statements about life elsewhere in the universe is best supported by current evidence? a. we have good evidence that life exists on many planets around other stars b. we only have evidence that life exists around three other stars c. the government has evidence (which it is not releasing) that there is at least one other intelligent life form on a planet orbiting another star d. while we have evidence of the building blocks of life elsewhere in the universe, we have no definite evidence about life around other stars at this time e. there is no evidence for intelligent life anywhere, even on Earth
d
If we want to see what galaxies looked like at a time close to the beginning of the universe, where should we look? a. in the Local Group of galaxies b. within the nearest 100 million light years from the Milky Way c. near the center of the Virgo Cluster of galaxies d. in a direction away from the plane of the Milky Way, where we can see very faint galaxies that are more than 10 billion light years away e. it doesn't matter; you can look at any galaxy, because all galaxies look pretty much the same today as they did in the early days of the universe
d
In the very distant future, given our best model of the accelerating universe, what will the universe look like? a. all the galaxies will start showing blue-shifts b. the universe will look pretty much the same as it does today c. the entire universe will become one huge black hole d. all the stars will die and the galaxies will be dark e. galaxies will shine even more brightly than today from all the dark energy
d
One important way astronomers can learn in some detail about what happens when galaxies collide is a. to watch the Andromeda Galaxy (M31,) which is on a collision course with us, for a decade b. to look at the supermassive black hole at the center of the Milky Way c. to examine the satellite galaxies presently orbiting the Milky Way d. to simulate galaxy collisions on a large computer and watch what the simulation predicts e. to look at videos of car accidents that are particularly violent
d
Photosynthesis was a great step forward in the evolution of life on Earth, because with photosynthesis a. we have the way in which life on Earth and life on Mars resemble each other b. life could, for the first time, reproduce (make copies of itself) c. we have the common ancestor that gave rise to every species of life now on Earth d. life could extract chemical energy from sunlight e. life did not have to evolve any further
d
Scientists speculate that the properties (laws) of the universe must be the way they are because if they were significantly different, we would not be here to think about them. This idea is called a. the cosmological principle b. the Hubble law c. the narcissus conjecture d. the anthropic principle e. the inflationary self-image hypothesis
d
The "great voids" that astronomers studying galaxies are finding are: a. regions where a number of black holes have cleared out space in the center of a galaxy b. empty regions between the spiral arms of the Milky Way Galaxy c. huge regions inside spiral galaxies, where the powerful radiation from a very hot star has cleared out the local interstellar material d. very large regions of intergalactic space, where relatively few galaxies or galaxy clusters can be found e. regions inside the brains of astronomy students where information about astronomy topics should have been located, but has been lost
d
The Sloan Digital Sky Survey a. searches for planets around neighbor stars by looking for changing Doppler shifts in their spectra b. searches for Trans-Neptunian objects, small icy bodies in the outer solar system, whose orbits sometimes resemble Pluto's c. searches for supernova remnants that could have pulsars inside and then try to find the pulsars d. takes images and spectra of millions of objects, to find the positions and redshifts of as many galaxies and quasars as possible e. searches to see whether extra-terrestrial civilizations are sending any digitally recorded music our way
d
The model of the universe that involves an enormous increase of scale during a very short time in the early universe is called: a. the flat universe model b. the oscillating universe model c. the primeval atom model d. the inflationary universe model e. the cosmic burp model
d
The standard bulbs (standard candles) that made it possible for astronomers to discover the acceleration in the expansion of the universe were a. globular clusters b. Cepheid variable stars c. the brightest irregular galaxy in a rich cluster d. Type Ia supernovae e. the size of a galaxy dark matter halo
d
The two scientists who first discovered the cosmic microwave background radiation were: a. Hubble and Humason b. Einstein and Friedmann c. Gamow and Alpher d. Penzias and Wilson e. Kirk and Spock
d
What do the surveys of the three-dimensional distribution of groups of galaxies reveal about how groups and clusters of galaxies are organized? a. galaxy groups are distributed completely evenly -- there is typically the same amount of space between them -- and so there is no structure evident b. galaxy groups make a huge spiral structure that resembles the Milky Way (but is much bigger) c. galaxy groups are organized into huge spherical "lumps" with concentric rings of groups of galaxies around each lump d. galaxy groups are organized into huge filaments with great voids between them -- something like the structure one would see taking a cross-section of some soap bubbles e. you can't fool me; astronomers cannot get any sense with our present-day instruments of how groups of galaxies are distributed on the large scale
d
What is the strongest known force in the universe? a. gravity b. the electromagnetic force c. the weak nuclear force d. the strong nuclear force e. The Dallas Cowboys [put in your favorite local sports team here]
d
What makes the Earth different from the other worlds that might have life in the solar system (and easier to detect from far away) is that only Earth a. has liquid water on it; no other world in our solar system has water b. has temperatures in some places where chemical change is possible c. has a solid surface d. has a biosphere on its surface where photosynthesis can take place e. has the chemical ingredients from which life might begin
d
When they talk about the Copernican principle, philosophers and astronomers mean that: a. the idea that Copernicus was the greatest astronomer who ever lived and the model for astronomers ever since b. the idea that everything in the universe revolves around the Sun c. the idea that everything in the universe rotates and revolves (i.e. has angular momentum) d. the idea that there is nothing special about our place in the universe e. the idea that the universe is expanding in every direction that we look
d
Where in space did the expansion of the universe begin? a. at the center of the Milky Way Galaxy; that's why all the other galaxies are moving away from us b. near the center of the Virgo Supercluster of Galaxies c. at a point so far away that only our largest telescopes can show us glimpses of it d. everywhere at once e. nowhere at all; new observations show that the universe is not expanding after all
d
Which of the following did NOT happen during the first few minutes after the Big Bang? a. temperatures throughout the universe were hotter than the cores of stars are today b. two or three of the simplest elements fused together c. energy was converted to matter d. some very massive early stars formed e. matter and antimatter collided and turned into energy
d
Which of the following does NOT happen when two galaxies collide? a. large interstellar gas clouds collide b. the rate of star formation increases c. the shape of the galaxy is often changed d. many of the stars in one galaxy collide with the stars in the other e. a smaller galaxy may wind up inside a larger one
d
Astronomers can now report that active star formation was going on at a time when the universe was only 20% as old as it is today. When astronomers make such a statement, how can they know what was happening inside galaxies way back then? a. they look at the open clusters in the Milky Way Galaxy b. they look at radio waves coming from nearby active galaxies c. they look at a graph that shows the way galaxy redshifts change with time d. they look at the elements in comets, which formed when our solar system was first forming e. they examine the spectra of galaxies (or the overall colors of galaxies) with the highest redshifts they can find
e
If you want to check on what conditions were like in the universe a few hundred thousand years after the Big Bang, what sort of instrument would it be best to use: a. a gamma-ray or high-energy x-ray telescope in orbit b. a tank of chlorine deep inside the Earth c. a small refractor (which gathers visible light) on a college campus, but pointed in just the right direction d. an ultra-violet telescope in orbit around Jupiter e. a satellite with infrared and microwave telescopes on board
e
In which of the following places have astronomers NOT found evidence for the building blocks of life (organic compounds)? a. Earth b. comets c. meteorites d. clouds of interstellar gas and dust e. we have found evidence for such materials in all of the above sites
e
Scientists are impressed with extremophiles, life forms that can survive under what seems to humans to be extremely unpleasant conditions. In which of the following environments have we not found life: a. temperatures near or below the freezing point of water b. temperatures near or above the boiling point of water c. very acid environments d. conditions where the radiation dosage is high e. conditions resembling the photosphere of the Sun
e
What discovery about Saturn's moon Enceladus has encouraged astronomers to think of that moon as a possible place where life might exist? a. Enceladus has a strong magnetic field b. Enceladus has rivers of liquid water flowing on its surface c. There are radio signals coming from Enceladus which indicate they might be made by intelligent life d. Enceladus has a thick atmosphere with a significant amount of oxygen e. There are plumes of salty vapor coming from cracks in Enceladus' surface
e
Which of the following is not a way that astronomers can find how much dark matter there is in cluster of galaxies? a. measuring the speeds with which the galaxies are moving around, to estimate the mass of the cluster needed to keep them from moving away b. measuring how much slower galaxies in a rich cluster or supercluster are moving than the Hubble Law would predict c. observing x-rays from the hot gas in the cluster, and using the amount of x-ray radiation to estimate the mass of the cluster d. using gravitational lensing effects to make a map of how much mass a cluster of galaxies contains e. observe the radio waves coming from all dark matter; from the strength of the radio waves from each cluster, estimate the amount of dark matter needed to produce them
e
Which of the following is not true about the Local Group of galaxies (of which the Milky Way is a member)? a. it is a member of the same supercluster as the Virgo Cluster b. it has few galaxies when compared to a rich cluster c. the Milky Way is one of its more massive members d. it has more elliptical galaxy members than spiral galaxies e. it has about a thousand member galaxies
e
Which of the following is pretty good evidence that the universe began with a Big Bang? a. the fact that galaxies collide b. the fact that stars explode c. the fact that all the galaxies are moving toward us d. the existence of a double star system like Cygnus X-1 e. the 3-degree cosmic microwave background radiation
e
