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- 1. Open EndedWhen chemists say that a planet's upper regions are reduced,they mean that these regions
- 2. Open EndedA planet in our solar system whose composition resembles that of our Sun is:
- 3. Open EndedOn which of the planets (other than Earth) could a human being step out of a spacecraft and survive without any protective gear (special suit, oxygen tanks, etc)? Group of answer choices
- 4. Open EndedIn the far future, a visiting tourist from another planetary system asks to see the most massive object in our solar system. Where would you take him/her/it?
- 5. Open EndedAll the planets (without exception)
- 6. Open EndedWhat is the most important reason that astronomers have learned more about our planetary system in the last 30-40 years than all of history before then.
- 7. Open EndedThe first trans-Neptunian object astronomers found (in 1930) is called
- 8. Open EndedIn studying the surfaces of solid bodies in the solar system, astronomers have learned that the number of craters (per unit area):
- 9. Open EndedIn the four terrestrial planets, the densest, heaviest materials are at the center and not evenly distributed throughout the planet. Scientists interpret this observation to mean that:
- 10. Open EndedOne way in which the ozone layer is useful for life forms on the Earth's surface is that it
- 11. Open EndedWhat relatively recent event shows that impacts continue to happen in our solar system even today?
- 12. Open EndedWhich of the following points about our planet's atmosphere is FALSE?
- 13. Open EndedAn increase in the Earth's temperature by several degrees Celsius would result in:
- 14. Open EndedWhich of these did the June 1908 impact event in Siberia and the 2013 event in the Russian city of Chelyabinsk have in common?
- 15. Open EndedToday, a significant amount of new gas is joining the atmosphere of the Earth from what source:
- 16. Open EndedFor scientists, one bar is
- 17. Open EndedIn which region of the Earth's atmosphere have you spent most of your life?
- 18. Open EndedScientists have been concerned about a set of industrial chemicals called CFC's (chlorofluorocarbons) because they:
- 19. Open EndedToday, scientists believe that the main reason the Earth has had periodic ice ages is:
- 20. Open EndedSometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this?
- 21. Open EndedThe lunar highlands are made mostly of rocks that
- 22. Open EndedWhich of the following is NOT something that was accomplished by the Apollo missions to the Moon?
- 23. Open EndedThe large, roughly circular, dark, and somewhat younger regions on the Moon are called:
- 24. Open EndedWhat makes astronomers think that impact rates for the Moon must have been higher earlier than 3.8 billion years ago?
- 25. Open EndedWhich of the following statements about our Moon is FALSE?
- 26. Open EndedMercury is a small planet and therefore has trouble holding on to an atmosphere. How then do scientist account for the extremely thin atmosphere that was found around the planet in 1985?
- 27. Open EndedWhy are almost all the craters we see on the Moon circular?
- 28. Open EndedWhat is one important way in which both the Moon and Mercury are different from Earth?
- 29. Open EndedWhich of the following is a way that the planet Mercury is similar to the Moon?
- 30. Open EndedWhy are the largest craters we find on the Moon and Mercury so much larger than the largest craters we find on the Earth?
- 31. Open EndedThese days the theory of the Earth's Moon's origin that best fits with the facts we have about the Moon is:
- 32. Open EndedWhen a projectile (a rock from space, say) hits the surface of the Moon, which of the following do we NOT get?
- 33. Open EndedWhich of the following statements about Mercury's orbit is TRUE?
- 34. Open EndedWhat formation or formations are evidence that the planet Mercury may have shrunk (gotten a bit smaller) as it cooled?
- 35. Open EndedThe mountains on the moon were created by
- 36. Open EndedWhat theory of Mercury's origin can best explain the fact that its core is made of such dense materials?
- 37. Open EndedWe believe the maria on the Earth's Moon are:
- 38. Open EndedWhat is one way that astronomers have actually gotten an idea of the age of the surfaces of terrestrial planets other than the Earth?
- 39. Open EndedDuring the process of differentiation,
- 40. Open EndedIn a bad late-night science fiction film, a villain is using a large collection of rare radioactive atoms as energy for a weapon to threaten the good guys. The atoms have a half-life of 1 hour. The villain has 4 kilograms of the radioactive material now, and he needs a minimum of 1 kg. for his weapon to work. After how much time will the weapon no longer be a threat?
- 41. Open EndedThe rate at which a collection of the same radioactive atoms will decay depends on:
- 42. Open EndedWhich of the eight planets has a smaller mass than Mercury?
- 43. Open EndedWhich of the following statements about the rocks brought back from the Earth's Moon by the astronauts is TRUE?
- 44. Open EndedOf the people who landed on the Moon, how many were trained scientists?
- 45. Open EndedThe first human being to step out onto the surface of another world was:
- 46. Open EndedWhich of the following statements about the atmosphere of Mars today is FALSE?
- 47. Open EndedOne of the most impressive features of the geology of Mars is an uplifted area about the size of North America, with volcanoes on it, which is called the
- 48. Open EndedAbout 75% of the surface of Venus consists of
- 49. Open EndedThe process by which Venus became so much hotter than the Earth is called:
- 50. Open EndedWhich of the following is NOT a correct statement about the rotation of Venus?
- 51. Open EndedThe largest volcano on Mars is called:
- 52. Open EndedThe same gas makes up most of the atmosphere of Mars and Venus. This gas is:
- 53. Open EndedMars appears to have long branching channels that have the appearance of being formed by a flowing liquid. Yet we know that liquids would not stay liquid in the very thin atmosphere we have on the Martian surface? So how can we explain the channels?
- 54. Open EndedAstronomers estimate that the plains of Venus are only about 500 to 600 million years old. How do they estimate dates like this?
- 55. Open EndedValles Marineris is a wide, deep network of chasms stretching for some 2500 miles on the surface of Mars. How do we believe such a big set of canyons formed originally?
- 56. Open EndedThe highest mountain on Venus is also the only feature to be named after a man; its namesake is the Scottish scientist who laid the foundations for our understanding of electro-magnetic waves. This is Mount:
- 57. Open EndedThe planet that most resembles the Earth in size and internal composition is
- 58. Open EndedThe large circular coronae on Venus are:
- 59. Open EndedThe person who really publicized the idea of canals on Mars and impressed it on the public mind was:
- 60. Open EndedWhy is it so much easier to determine the length of the day on Mars than on Venus?
- 61. Open EndedWhich of the following would NOT be one of the problems faced by an unprotected Earthling stranded on Mars? (Unprotected meaning no space suit.)
- 62. Open EndedThe largest continental (highland) area on Venus is called:
- 63. Open EndedThe first spacecraft to orbit another planet circled Mars in 1971. It was:
- 64. Open EndedWhy are there no smaller craters on the surface of Venus, only bigger ones?
- 65. Open EndedWhat planet can come closest to the Earth in its orbit and look brightest in our skies?
- 66. Open EndedWhich of the following is NOT a way we have studied the planet Mars so far?
- 67. Open EndedThe canals that late 19th and early 20th observers thought they saw on Mars turned out to be:
- 68. Open EndedA crucial difference that helps explain why Venus is so hot and the Earth isn't is that:
- 69. Open EndedOne way in which Mars closely resembles the Earth is:
- 70. Open EndedThe first spacecraft which did not merely fly by a jovian (or giant) planet, but actually went into orbit around it for an extended period of time was:
- 71. Open EndedWhich of the following does the composition of a planet like Jupiter resemble:
- 72. Open EndedThe Red Spot of Jupiter is:
- 73. Open EndedWhich of the following is NOT a correct statement about the ways the jovian planets differ from the terrestrial planets?
- 74. Open EndedThe bluish color that makes the atmosphere of Neptune so beautiful to the human eye is caused by the interaction of sunlight with what gas?
- 75. Open EndedThe rings of the outer planets consist of
- 76. Open EndedThe four large moons of Jupiter were first discovered by:
- 77. Open EndedFor a while, after the space age began, astronomers did not know what the surface of Titan looks like, but today they do. Which of the following was NOT a method by which astronomers have learned about the surface of Titan?
- 78. Open EndedThe largest and most massive of Saturn's rings is the ____ Ring
- 79. Open EndedWhat do astronomers think is the origin of the many irregular moons around the outer planets (irregular meaning they are orbiting backwards and/or have eccentric orbits)?
- 80. Open EndedWhen two objects in orbit have periods of revolution that are simple ratios of each other (such as 1 to 2 or 1 to 3) we say that we have:
- 81. Open EndedThe Galileo spacecraft measured that the moon Ganymede had a magnetic field, indicating that its interior was at least partly melted and warm. What do scientists think is the most likely reason for this?
- 82. Open EndedWhich of the jovian planets does NOT have any satellites?
- 83. Open EndedWhich planet has the biggest moon relative to its own size? Not the biggest moon in terms of kilometers, but the biggest as a percentage of the size of the planet it orbits
- 84. Open EndedHow does Saturn's F ring stay so thin (narrow), when the other rings are so wide?
- 85. Open EndedWhich of the following is NOT a way that the moon Titan probably resembles the Earth?
- 86. Open EndedThe satellite which has the thickest atmosphere (so thick that it's quite a surprise for a satellite) is:
- 87. Open EndedWhen astronomers say that Ganymede is a differentiated body, they mean that it:
- 88. Open EndedWhat makes the rings of Neptune different from those of other planets we know?
- 89. Open EndedJupiter has enough mass to make 318 Earths. In contrast, Uranus and Neptune have only enough mass to make:
- 90. Open EndedThe largest planet in the solar system (by mass) is:
- 91. Open EndedThe planet that orbits "on its side" (i.e. has its rotation axis perpendicular to the plane of its orbit) is:
- 92. Open EndedThe planet that has an axis that points roughly straight up, and thus has no seasons to speak of, is:
- 93. Open EndedIn the far future, a daring interplanetary tourist wants to go "hang-gliding" on the jovian planet with the highest equatorial wind speeds. Which planet would have the fastest wind at its equator?
- 94. Open EndedAt the moment when the Voyager spacecraft got closest to Uranus, the Sun was shining directly on the planet's south pole. Uranus takes about 17 hours to rotate once on its axis. If Voyager took a photo of the south pole 8.5 hours later, what would it observe?
- 95. Open EndedWhich of the following is NOT one of the largest moons in the Solar System?
- 96. Open EndedWhich of the following statements about Saturn's rings is TRUE?
- 97. Open EndedWhich of the following worlds does NOT have a ring?
- 98. Open EndedThe moon Triton orbits which of the planets?
- 99. Open EndedThe majority of the moons orbiting the outer (jovian) planets are:
- 100. Open EndedWhat evidence can you give that shows the surface of Jupiter's moon Europa must be relatively young?
- 101. Open EndedMuch of what we have learned about the jovian planets and their satellites has come from the work of two spacecraft called:
- 102. Open EndedCallisto, the fourth moon of Jupiter's, takes 17 days to orbit Jupiter. If I stand on the surface of Callisto and see Jupiter high in the sky over my head, and then wait 8.5 Earth days in the same spot, where will I see Jupiter?
- 103. Open EndedThe satellite whose surface is characterized by a smooth icy crust with a complex network of cracks is:
- 104. Open EndedThe lakes found in the north polar region of Titan are filled with liquid
- 105. Open EndedComets get significantly brighter in our skies as they approach the Sun because
- 106. Open EndedWhich of the following statements about NEO's (Near Earth Objects) is TRUE?
- 107. Open EndedShort-period comets like Comet Halley
- 108. Open EndedHow have astronomers learned what different asteroids are made of?
- 109. Open EndedDifferent asteroids reflect different percentages of the light falling on them. This is due to the fact that they have different:
- 110. Open EndedComets change as they approach the Sun in their orbits. Which of the following statements about a comet approaching the Sun is FALSE?
- 111. Open EndedAccording to our textbook, what is the best way to defend ourselves against an asteroid which is on course to collide with the Earth in 7 years?
- 112. Open EndedMore than 75% of the known asteroids:
- 113. Open EndedWhich part of a comet is the DENSEST?
- 114. Open EndedA main difference between asteroids and comets is that asteroids are mostly made of rock and comets are mostly made of
- 115. Open EndedIf there are at least a million asteroids, how did spacecraft like Galileo survive their trip through the asteroid belt?
- 116. Open EndedWhich of the following statements about the tails of comets is FALSE?
- 117. Open EndedThe reason that Olympus Mons, the tallest mountain on Mars, is taller than Mount Everest (the tallest mountain on Earth) is that (choose all that apply):
- 118. Open EndedOne way to find a new meteorite is to:
- 119. Open EndedWhich of the following is not a characteristic that worlds in our solar system have in common:
- 120. Open EndedOne of the following worlds has an orbit that actually crosses the orbit of another world. This "rude" world is:
- 121. Open EndedHow can astronomers measure the age of a meteorite that fell from the skies?
- 122. Open EndedOne of the best proofs that our theory of how the solar system formed is correct is that astronomers now observe
- 123. Open EndedAt the beginning of the solar system's history, a ready supply of proto-planets or mini-planets crashed into the developing planets and each other - something astronomers call the "era of giant impacts." How long do astronomers estimate this era lasted?
- 124. Open EndedThe ages of stony meteorites have been measured to be roughly equal to:
- 125. Open EndedHow do astronomers know that the age of the solar system is about 4.5 billion years old?
- 126. Open EndedAstronomers now believe that the differences in composition among the planets reflect what characteristic in the early solar system
- 127. Open EndedThe Murchison meteorite that was found in Australia in 1969 is important to scientists because it contained
- 128. Open EndedWhich of these worlds is the most active geologically?
- 129. Open EndedA type of planet that our surveys of exoplanets are revealing around other stars, but we don't have any examples of around the Sun are:
- 130. Open EndedAccording to astronomical tradition, who gets to suggest the name for a newly discovered asteroid?
- 131. Open EndedThe two asteroids from which close-up images and data have been returned by the Galileo spacecraft are:
- 132. Open EndedWhy were asteroids not discovered until the 19th century?
- 133. Open EndedWhen the Dawn spacecraft explored the largest asteroid Ceres, it discovered white spots that appear to be salt and volcanic mountains made of water ice. This led astronomers to which of the following ideas
- 134. Open EndedThe reason that worlds like the Earth are differentiated is that
- 135. Open EndedThe first technique that allowed astronomers to find exoplanets involved:
- 136. Open EndedA key difference between the protoplanets that formed in the outer solar system and those that formed in the inner solar system was that
- 137. Open EndedWhich of the following pieces of observational evidence does our modern "solar nebula" theory of the formation of the solar system NOT explain directly?
- 138. Open EndedThe most likely models of the planet Mercury indicate that more than half the planet may be composed of:
- 139. Open EndedSometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this?
- 140. Open EndedIn the for terrestrial planets, the densest, heaviest materials are at the center and not evenly distributed throughout the planet. Scientists interpret this observation to mean what:
- 141. Open EndedIn its overall composition, the Moon roughly resembles:
- 142. Open EndedWhere has frozen water has been discovered on the Moon?
- 143. Open EndedWhich of the following statements about temperature changes on Mercury is correct?
- 144. Open EndedIn what way is the Moon similar to the Earth?
- 145. Open EndedWhich planet in the solar system has not been examined by spacecraft instruments that have either flown by or orbited them?
- 146. Open EndedThe planet closest to the Sun in the solar system is
- 147. Open EndedIn radioactive dating, the measure scientists use to note how long (on average) a particular radioactive nucleus will take to decay is called its
- 148. Open EndedAccording to the giant impact hypothesis about the formation of the Moon, why did the Earth not break apart into many pieces when the giant impact happened
- 149. Open EndedSometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this
- 150. Open EndedMercury is a small planet and therefore has trouble holding on to an atmosphere. How then do scientist account for the extremely thin atmosphere that was found around the planet in 1985
- 151. Open EndedWhy does Mars have an overall reddish color when we see its surface from afar
- 152. Open EndedWhich of the following statements about the atmosphere of Mars today is FALSE
- 153. Open EndedAstronomers estimate that the plains of Venus are only about 500 to 600 million years old. How do they estimate dates like this
- 154. Open EndedThe process by which Venus became so much hotter than the Earth is called
- 155. Open EndedWhich of the following is NOT a way that Venus resembles the Earth
- 156. Open EndedMars appears to have long branching channels that have the appearance of being formed by a flowing liquid. Yet we know that liquids would not stay liquid in the very thin atmosphere we have on the Martian surface? So how can we explain the channels
- 157. Open EndedThe highest mountain on Venus is also the only feature to be named after a man; its namesake is the Scottish scientist who laid the foundations for our understanding of electro-magnetic waves. This is Mount
- 158. Open EndedThe same gas makes up most of the atmosphere of Mars and Venus. This gas is
- 159. Open EndedWhich of the following statements about Valles Marineris, the great "grand canyon system" on Mars is true
- 160. Open EndedThe person who really publicized the idea of canals on Mars and impressed it on the public mind was
- 161. Open EndedThe canals that late 19th and early 20th observers thought they saw on Mars turned out to be
- 162. Open EndedI want to examine the surface of a planet which is completely covered by a thick layer of clouds all the time. What wavelength of electromagnetic radiation would I be smartest to use
- 163. Open EndedA crucial difference that helps explain why Venus is so hot and the Earth isn't is that
- 164. Open EndedWhy is it so much easier to determine the length of the day on Mars than on Venus
- 165. Open EndedAstronomers believe that Mars formed with a much thicker atmosphere than it has today. Where did this atmosphere go?
- 166. Open EndedThe troposphere (the lowest layer in the atmosphere) of Venus
- 167. Open EndedThe largest volcano on Mars is called
- 168. Open EndedThe first spacecraft to orbit another planet circled Mars in 1971. It was
- 169. Open EndedThe observation that began the 19th and early 20th century fascination with Mars as a place for life was
- 170. Open EndedThe bluish color that makes the atmosphere of Neptune so beautiful to the human eye is caused by the interaction of sunlight with what gas
- 171. Open EndedThe Red Spot of Jupiter is
- 172. Open EndedThe first spacecraft which did not merely fly by a jovian (or giant) planet, but actually went into orbit around it for an extended period of time was
- 173. Open EndedWhich of the following is NOT a correct statement about the ways the jovian planets differ from the terrestrial planets
- 174. Open EndedThe ages of stony meteorites have been measured to be roughly equal to
- 175. Open EndedHow do astronomers know that the age of the solar system is about 4.5 billion years old
- 176. Open EndedOne of the following worlds has an orbit that actually crosses the orbit of another world. This "rude" world is
- 177. Open EndedThe reason that Olympus Mons, the tallest mountain on Mars, is taller than Mount Everest (the tallest mountain on Earth) is that (choose all that apply)
- 178. Open EndedAt the beginning of the solar system's history, a ready supply of proto-planets or mini-planets crashed into the developing planets and each other - something astronomers call the "era of giant impacts." How long do astronomers estimate this era lasted
- 179. Open EndedThe fact that some asteroids cluster in what are called asteroid families is probably the result of
- 180. Open EndedA baseball pitcher wants to impress his girl-friend with how strong his throwing arm is. On which of the following bodies would the pitcher be MOST likely to be able to throw a baseball (a fast ball) so fast it would actually go into orbit
- 181. Open EndedThe scientist who first proposed that comet nuclei were "dirty snowballs" was
- 182. Open EndedHalley's Comet was given that name because Edmond Halley was
- 183. Open EndedOne reason we know more about the surface composition of the asteroid Vesta than about most other members of the asteroid belt is that
- 184. Open EndedOne way to find a new meteorite is to
- 185. Open EndedA type of planet that our surveys of exoplanets are revealing around other stars, but we don't have any examples of around the Sun are:
- 186. Open EndedAstronomers call the vast, rotating cloud of vapor and dust from which the solar system formed:
- 187. Open EndedWhen the solar system was forming, the building blocks from which the protoplanets gathered together were the
- 188. Open EndedThe atmosphere of Venus is mostly carbon dioxide, and the atmosphere of the Earth has water vapor. Why are these two gases absent in the atmosphere of the satellite around Saturn called Titan
- 189. Open EndedAccording to our textbook, what is the best way to defend ourselves against an asteroid which is on course to collide with the Earth in 7 years
- 190. Open EndedDifferent asteroids reflect different percentages of the light falling on them. This is due to the fact that they have different
- 191. Open EndedMore than 75% of the known asteroids
- 192. Open EndedComets change as they approach the Sun in their orbits. Which of the following statements about a comet approaching the Sun is FALSE
- 193. Open EndedWhat makes the rings of Neptune different from those of other planets we know
- 194. Open EndedWhich of the jovian planets does NOT have any satellites
- 195. Open EndedThe satellite which has the thickest atmosphere (so thick that it's quite a surprise for a satellite) is
- 196. Open EndedThe four large moons of Jupiter were first discovered by
- 197. Open EndedFor a while, after the space age began, astronomers did not know what the surface of Titan looks like, but today they do. Which of the following was NOT a method by which astronomers have learned about the surface of Titan
- 198. Open EndedThe laws of nature (as determined by scientists) can be described many ways.
- 199. Open EndedLight travels 3 x 105meters every second. That number in words is 30 meters
- 200. Open EndedThe way scientists know that a hypothesis in astronomy is a reasonable description of nature is to
- 201. Open EndedA large body in space that consistently makes its own light (instead of merely reflecting another body's light) is called
- 202. Fill in the BlankThe location of the Earth in the Milky Way Galaxy is _____.
- 203. Fill in the BlankA light year is ______.
- 204. Open EndedThe Astronomical Unit (AU) as defined by astronomers is
- 205. Open EndedWhich of the following is the Earth NOT located in?
- 206. Open EndedEven with the best and largest telescopes, we can't see all the stars in the Milky Way Galaxy, even though these same telescopes can show us other galaxies. This is because
- 207. Open EndedThe smallest piece of an element (like gold or lead) that still has all the properties of that element is called
- 208. Open EndedYou are on a camping trip, far away from city lights. You look up into the dark night sky, and see lots of stars, some brighter, some dimmer. All the stars you see with your unaided eye are
- 209. Open EndedFor scientists, an element (like gold) is defined by
- 210. Open EndedThe laws of nature (as determined by scientists) can be described many ways. Mark all that are correct.
- 211. Open EndedAll molecules (like molecules of water or carbon dioxide) are made up of
- 212. Open EndedWhen the authors of our textbook say that astronomers are like police detectives trying to solve crimes, they are explaining that
- 213. Open EndedFrom a city in the U.S., where in the sky would you look to see a star that is not turning with the motion of the sky in the course of a night?
- 214. Open EndedThe 88 sectors into which astronomers today divide the celestial sphere (the whole sky) are called:
- 215. Open EndedThe point in the sky directly above your head at any given time is called the
- 216. Open EndedWhen it comes to our place in the solar system today, which model do we accept?
- 217. Open EndedIn what fundamental way did the work of Galileo differ from his predecessors who had thought about the sky?
- 218. Open EndedThe Renaissance astronomer who wrote the pioneering book that suggested the Earth probably orbits the Sun (instead of the other way around) was:
- 219. Open EndedHow did Eratosthenes measure the size of the Earth?
- 220. Open EndedThe Sun's apparent path around the celestial sphere is called
- 221. Open EndedThe Renaissance astronomer who wrote the pioneering book that suggested the Earth probably orbits the Sun (instead of the other way around) was:
- 222. Open EndedIf the Earth goes around the Sun, why is the ecliptic not lined up with the celestial equator?
- 223. Open EndedWhen a planet temporarily moves westward in the sky over the course of several weeks or months (instead of eastward, as it typically does), we call it
- 224. Open EndedThe scientist who first devised experimental tests to demonstrate the validity of the heliocentric model of the solar system was
- 225. Open EndedFrom horizon to opposite horizon, the sky takes up how much angular distance?
- 226. Open EndedThe slow tipping of the Earth's axis in a circle with a period of about 26,000 years is called
- 227. Open EndedIn Ptolemy's system the planets orbit the Earth rather than the Sun. How did this system explain the retrograde motion of planets like Jupiter?
- 228. Open EndedThe star that is currently closest to the North Celestial Pole is
- 229. Open EndedWhat problem has precession caused for many of the schools of astrology?
- 230. Open EndedIn the Northern Hemisphere, the altitude (height in degrees above the horizon) of the North Star is always roughly equal to the
- 231. Open EndedNewton's reformulation of Kepler's third law allows us to measure the masses of bodies in orbit around each other, if we can measure:
- 232. Open EndedThe scientist who formulated the three laws of planetary motion by analyzing the data on the precise location of planets in the sky was:
- 233. Open EndedTo come up with the precise mathematical form of his law of gravity, Newton first had to invent the mathematical techniques that we now call:
- 234. Open EndedThe asteroid belt is
- 235. Open EndedWhich of the following statements about forces are TRUE? Mark all that apply.
- 236. Open EndedWhich of the following are reasons why many people consider Isaac Newton one of the greatest scientists who ever lived? Mark all that are correct.
- 237. Open EndedThe idea that objects (in the absence of an outside force) tend to continue doing what they are already doing is called the law of
- 238. Open EndedIf the moon is at first quarter right now, how long do you have to wait to see the full moon?
- 239. Open EndedFrom a particular location on Earth, why can we see many more total eclipses of the Moon than total eclipses of the Sun?
- 240. Open EndedWhich of the following is an important part of the reason it is hotter in summer in North America than in winter?
- 241. Open EndedThe Earth is closest to the Sun in which month of the year?
- 242. Open EndedWhat phase of the Moon must it be to have a solar eclipse?
- 243. Open EndedHow does the Sun influence the tides that we experience on Earth?
- 244. Open EndedWhen the Sun and Moon are lined up and pull together, the tides they raise are called:
- 245. Open EndedThe planet in our solar system whose orbit actually brings it inside the orbit of another planet is
- 246. Open EndedAstronomers discover a new comet that orbits the Sun, but has its aphelion (the furthest point in its orbit) beyond Neptune. Astronomers studying this comet have the right to expect that it:
- 247. Open EndedThe planet in our solar system with the shortest period of revolution is
- 248. Open EndedWhen NASA and a group of astronomers sent up a spacecraft designed to find planets orbiting other stars, they named it after Kepler. Why was this an appropriate name?
- 249. Open EndedAn astronomy textbook, when printed out, weighs four pounds on the surface of the Earth. After finishing your course, you are so tired of the book, you arrange for NASA to shoot it into space. When it is twice as far from the center of the Earth than when you were reading it, what would it weigh? (Note, assume that the book has been moving away from the Earth, not falling freely around it.)
- 250. Open EndedWhy do astronauts (and cans of soft drink) float around in the Shuttle instead of falling?
- 251. Open EndedIf there really were a Santa Claus at the North Pole, what would the cycle of the seasons be like for him and Mrs. Claus?
- 252. Open EndedRecently, the media, always trying to make things sound sensational, have started to call totally eclipsed moon "the blood moon." Why does the Moon look reddish to us when there is a total lunar eclipse?
- 253. Open EndedSome college students decide to form a secret society that would meet each year after graduation at a time when the day and night were the same length. Which of the following would be a time they could meet?
- 254. Open EndedIn locating objects on the celestial sphere, we call the number of degrees east or west that something is from Greenwich, England its
- 255. Open EndedHow do astronomers learn what elements are present in a given star?
- 256. Open EndedMost ultraviolet radiation does not penetrate to the Earth's surface. Instead it is absorbed in:
- 257. Open EndedNot all wavelengths of electromagnetic radiation can penetrate the Earth's atmosphere. Of the following types of waves that come from space, which one are you likely to be able to detect most easily from our planet's surface:
- 258. Open EndedWhen white light passes from the air into a different medium such as glass, it:
- 259. Open EndedAstronomers observe a typical star using a telescope and a spectrometer. They will see:
- 260. Open EndedWhy is an absorption spectrum especially useful for astronomers?
- 261. Open EndedThe scientist who worked out the mathematics of the connections between electricity, magnetism, and light in the 19th century was:
- 262. Open EndedWhich of the following statements about our Moon is FALSE?
- 263. Open EndedMercury is a small planet and therefore has trouble holding on to an atmosphere. How then do scientist account for the extremely thin atmosphere that was found around the planet in 1985?
- 264. Open EndedWhy are the largest craters we find on the Moon and Mercury so much larger than the largest craters we find on the Earth?
- 265. Open EndedThe large, roughly circular, dark, and somewhat younger regions on the Moon are called:
- 266. Open EndedWhich of the following is NOT something that was accomplished by the Apollo missions to the Moon?
- 267. Open EndedThe lunar highlands are made mostly of rocks that
- 268. Open EndedSometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this?
- 269. Open EndedA planet in our solar system whose composition resembles that of our Sun is:
- 270. Open EndedWhat is one way that astronomers have actually gotten an idea of the age of the surfaces of terrestrial planets other than the Earth?
- 271. Open EndedWhat is the most important reason that astronomers have learned more about our planetary system in the last 30-40 years than all of history before then.
- 272. Open EndedThe planet closest to the Sun in the solar system is:
- 273. Open EndedIn radioactive dating, the measure scientists use to note how long (on average) a particular radioactive nucleus will take to decay is called its:
- 274. Open EndedWhen chemists say that a planet's upper regions are reduced,they mean that these regions
- 275. Open EndedWhat formation or formations are evidence that the planet Mercury may have shrunk (gotten a bit smaller) as it cooled?
- 276. Open EndedWhat is one important way in which both the Moon and Mercury are different from Earth?
- 277. Open EndedWhen a projectile (a rock from space, say) hits the surface of the Moon, which of the following do we NOT get?
- 278. Open EndedThe red color we see on a lot of photographs of nebulae comes from which element?
- 279. Fill in the BlankThe _____ is the cycling of mass in and out of the interstellar medium, including accretion of gas from intergalactic space, loss of gas back into intergalactic space, and conversion of interstellar gas into stars
- 280. Open EndedAmong interstellar clouds, the hotter the cloud, the
- 281. Open EndedAstronomers studying regions like the Orion Giant Molecular Cloud have observed that a wave of star formation can move through them over many millions of years. What sustains such a wave of star formation in a giant molecular cloud?
- 282. Fill in the BlankA _____ is a very young star still in the process of formation, before nuclear fusion begins
- 283. Open EndedWhich of the following is not a place where astronomers believe interstellar dust grains can form?
- 284. Fill in the BlankThe _____ is the region of ionized hydrogen in interstellar space
- 285. Fill in the Blank_____ is an empirical relation between the periods and luminosities of certain variable stars
- 286. Open EndedThe first (living) star other than our own Sun found to have more than one planet orbiting it is called
- 287. Open EndedHow do astronomers know that pulsating variable stars are actually expanding and contracting in diameter?
- 288. Open EndedSupposing we launched a very fast dart from the Space Shuttle, pointed in some direction away from any planet, so that it could travel beyond the solar system. What would it be most likely to hit first after traveling outward for a while?
- 289. Open EndedWhat is the baseline that astronomers use to measure the parallax (the distance) of the nearest stars?
- 290. Open EndedIf an astronomer wants to find the distance to a star that is not variable and is located too far away for parallax measurements, she can:
- 291. Open EndedAn astronomer is observing a single star (and one which does not vary) which she knows is located about 30 light-years away. What was the most likely method she or her colleagues used to obtain that distance?
- 292. Open EndedAn astronomer wants to observe a cloud of dust in a relatively close part of the Galaxy. Unfortunately, this dust cloud is not located in the direction of a crowded region of stars. What instrument would be the most help in finding this cloud.
- 293. Open EndedThe dust in the dust clouds in interstellar space consists of
- 294. Open EndedIf a star is 20 parsecs away, its parallax must be:
- 295. Fill in the BlankThe _____ is a slightly denser cloud inside the Local Bubble, inside which the Sun also lies
- 296. Open EndedWhich of the following is NOT one of the reasons planets around other stars are so difficult to detect?
- 297. Open EndedWhy is it so difficult for astronomers to see new stars in the process of birth?
- 298. Open EndedThe higher the luminosity (intrinsic brightness) a Cepheid variable is,
- 299. Open EndedHow far away would a star with a parallax of 0.2 arcsec be from us?
- 300. Open EndedThe measurement of cosmic distances was helped tremendously by the discovery, in the early part of the 20th century, that in Cepheid variable stars, the average luminosity was related to:
- 301. Fill in the Blank_____, or interstellar matter, is the gas and dust between the stars in a galaxy
- 302. Open EndedThe amount of interstellar matter present in our Galaxy is always changing. Which of the following processes is NOT a major contributor to that change?
- 303. Open EndedA light curve for a star measures how its brightness changes with
- 304. Open EndedYou are an astronomer whose supervisor has just forbidden drinking alcoholic beverages near the observatory. In frustration, you under¬take a search for alcohol molecules in space. Where would your search be most likely to succeed?
- 305. Open EndedWhat is the closest star to the Sun?
- 306. Open EndedThe star now called Kepler-444 is 11 billion years old (much older than the Sun) and has five planets orbiting close to it. What has this system taught astronomers about the history of star formation?
- 307. Open EndedThe largest types of clouds found in interstellar space are
- 308. Open EndedWhen a star settles down to a stable existence as a main-sequence star, what characteristics determines where on the main sequence in an H-R diagram the star will fall?
- 309. Fill in the BlankA _____ is a planet that is intermediate between the largest terrestrial planet in our solar system (Earth) and the smallest jovian planet (Neptune); generally, they have sizes between 2.8 and 4 times Earth's size
- 310. Fill in the BlankAn _____ is a planet orbiting a star other than our Sun
- 311. Open EndedAstronomers have found large quantities of cold, neutral hydrogen gas in our galaxy. How is this gas distributed?
- 312. Open EndedAstronomers must often know the distance to a star before they can fully understand its characteristics. Which of the following properties of a star typically requires a knowledge of distance before it can be determined?
- 313. Open EndedWhich of the following descriptions of interstellar dust is FALSE?
- 314. Open EndedGiven the presence of dust throughout the disk of the Milky Way Galaxy, what is the best technique for learning about more distant regions of our galaxy's disk.
- 315. Open EndedWhich of these stars will take the SHORTEST time to go from the earliest protostar stage to the main sequence?
- 316. Open EndedTo measure how dense a planet is (to know whether it is made of rock or gas and liquid) they must be able to measure the planet's mass from the Doppler shift and
- 317. Open EndedAn astronomer is observing a star which puzzles her. The lines in the star's spectrum indicates that the star is very hot and should therefore be blue. But the star looks reddish in photographs and in measurements of the continuous spectrum. What is one possible explanation of this puzzle?
- 318. Fill in the BlankA _____ refers to luminous knots of gas in an area of star formation that are set to glow by jets of material from a protostar
- 319. Open EndedOur solar system has 8 planets orbiting the Sun. Based on the discoveries of exoplanets so far, what can we say about a star with 8 planets?
- 320. Open EndedWhat technique did astronomers use to make the first confirmed discovery of a planet around another star like the Sun?
- 321. Open EndedThe luminosity class of a star tells an astronomer
- 322. Open EndedToday, astronomers can measure distances directly to worlds like Venus, Mars, the Moon, or the satellites of Jupiter by
- 323. Open EndedWhen astronomers carefully examine the planets found by Kepler and draw conclusions from the Kepler sample, what do they conclude about planets the size of Earth?
- 324. Open EndedIf an astronomer wanted to find some relatively complex molecules in space, what technique should she use?
- 325. Fill in the BlankThe _____, or Local Hot Bubble, is a region of low-density, million degree gas in which the Sun and solar system are currently
- 326. Open EndedIn figuring out the evolutionary tracks on the H-R diagram, astronomers
- 327. Fill in the BlankA _____ is a variable star that pulsates in size and luminosity
- 328. Open EndedWhy did it take astronomers until 1838 to measure the parallax of the stars?
- 329. Open EndedA type of star that has turned out to be extremely useful for measuring distances is
- 330. Open EndedAstronomers were surprised to find so many Jupiter-mass planets so close to their stars. According to their best theories and models, such "hot Jupiters"
- 331. Fill in the Blank_____ are atomic nuclei (mostly protons) and electrons that are observed to strike Earth's atmosphere with exceedingly high energies
- 332. Fill in the Blank_____ is when one astronomical object moves in front of another
- 333. Fill in the BlankA _____ is a graph that displays the time variation of the light from a variable or eclipsing binary star or, more generally, from any other object whose radiation output changes with time
- 334. Fill in the Blank_____ consists of tiny solid grains in interstellar space thought to consist of a core of rocklike material (silicates) or graphite surrounded by a mantle of ices; water, methane, and ammonia are probably the most abundant ices
- 335. Open EndedYou are an astronomy graduate student and you are observing the big Orion Nebula from an airplane that has a good-sized infrared telescope built into it (there really is such a plane.) On an infrared image of the Nebula, what would particularly stand
- 336. Open EndedWhich of the following stars is a Cepheid variable?
- 337. Open EndedWhich type of star has the least amount of pressure in its atmosphere?
- 338. Fill in the Blank_____ is the attenuation or absorption of light by dust in the interstellar medium
- 339. Open EndedKepler's Laws can give us the relative distance of objects in the solar system. To convert these relative distances into actual distances, we need to:
- 340. Fill in the BlankA _____ is a cloud of interstellar gas or dust; the term is most often used for clouds that are seen to glow with visible light or infrared
- 341. Open EndedCosmic rays differ from other forms of interstellar matter by
- 342. Fill in the BlankA _____ is a star that belongs to a class of yellow supergiant pulsating stars; these stars vary periodically in brightness, and the relationship between their periods and luminosities is useful in deriving distances to them
- 343. Fill in the Blank_____ is a classification of a star according to its luminosity within a given spectral class; our Sun, a G2V star, has _____ V, for example
- 344. Open Endedhe closest star to the Sun, Proxima Centauri, was recently found to have a planet in its habitable zone. Proxima Centauri is a main sequence star with spectral type M. How would its habitable zone differ from the habitable zone of our Sun?
- 345. Fill in the Blank_____ is an apparent displacement of a nearby star that results from the motion of Earth around the Sun
- 346. Fill in the Blank_____ are large, cold interstellar clouds with diameters of dozens of light-years and typical masses of 10^5 solar masses; found in the spiral arms of galaxies, these clouds are where stars form
- 347. Open EndedWhere is the outer rim of the Local Bubble located today?
- 348. Fill in the BlankA _____ is a unit of distance in astronomy, equal to 3.26 light-years; at a distance of 1 _____, a star has a parallax of 1 arcsecond
- 349. Open EndedWhich of the following will show the smallest parallax shift?
- 350. Fill in the BlankThe term _____ refers to the reddening of starlight passing through interstellar dust because dust scatters blue light more effectively than red
- 351. Open EndedWith our current techniques, astronomers can typically only measure the minimum mass of a planet orbiting another star. To know the precise mass of the planet, they must also be able to determine
- 352. Open EndedAstronomers now understand that the dark regions or rifts visible in parts of our Galaxy that are otherwise crowded with stars are caused by:
- 353. Open EndedTo get the distance to a Cepheid variable star, astronomers must take several steps. Which of the following is NOT one of these steps?
- 354. Fill in the Blank_____ is the outflow of gas, sometimes at speeds as high as hundreds of kilometers per second, from a star
- 355. Open EndedThe light element lithium (which, on Earth, is part of medications that improve the lives of people with mental health illnesses) is more common in cosmic rays than it is in the Sun and the stars. What do astronomers think is the reason for this?
- 356. Open EndedAstronomers identify the "birth" of a real star (as opposed to the activities of a protostar) with what activity in the star?
- 357. Open EndedWhat observations about disks of dusty material around young stars suggest that planets may be forming in such disks?
- 358. Open EndedIf you want to find stars that are just being born, where are the best places to search?
- 359. Open Ended____ is one of a class of giant pulsating stars with periods shorter than 1 day, useful for finding distances
- 360. Open EndedA star whose temperature is increasing but whose luminosity is roughly constant moves in what direction on the H-R diagram?
- 361. Open EndedWhich of the following is NOT a way astronomers discover clouds of interstellar matter that have a large amount of dust in them?
- 362. Open EndedWhy can astronomers not tell from what direction a particular cosmic ray started toward the Earth?
- 363. Open EndedWhich of the following statements about the Sun's photosphere is NOT TRUE?
- 364. Open EndedWhat is the best reason astronomers have come up with to explain why sunspots are cooler and look darker?
- 365. Open EndedThe Sun's chromosphere and corona were discovered
- 366. Open EndedAstronomers have concluded that the Sun's activity varies in an 11-year cycle. Which of the following statements about this cycle is TRUE:
- 367. Open EndedThe most common element in the Sun is
- 368. Open EndedThe granulation pattern that astronomers have observed on the surface of the Sun tells us that:
- 369. Open EndedAs astronomers have learned more about the structure of the Sun, they have found that it
- 370. Open EndedCoronal Mass Ejections from the Sun have many serious effects on or near the Earth. Which of the following is NOT one of these effects?
- 371. Open EndedThe ten million tons of particles that escape the Sun each year in the form of the solar wind get out mainly through regions called
- 372. Open EndedSolar wind particles can be captured by the Earth's magnetosphere. When these particles spiral down along the magnetic field into the atmosphere, they are responsible for:
- 373. Open EndedThe Sun is an enormous ball of gas. Left to itself, a ball of so many atoms should collapse under its own tremendous gravity. Why is our Sun not collapsing?
- 374. Open EndedWhen energy is first produced by fusion deep in the core of the star, that energy moves outward mostly by what process?
- 375. Open EndedToday we realize that the source of energy for the Sun is a process called
- 376. Open EndedIn the Sun, when a positron and an electron collide, they will produce:
- 377. Open EndedWhich of the following particles has the lowest mass?
- 378. Open EndedThe material inside the Sun is in the form of a
- 379. Open EndedA friend (who does not have the new awareness which you have gained from this course) suggests that the mechanism that keeps the Sun shining as brightly as it does is the burning of coal. You brilliantly challenge his theory! Your challenge comes in several related steps; which of the following is one of those steps?
- 380. Open EndedWhich statement about the Sun's rotation is TRUE?
- 381. Open EndedHow do astronomers know how strong the magnetic field of the Sun is?
- 382. Open EndedAstronomers first detected the presence of a wind of particles coming from the Sun by
- 383. Open EndedWho pays the bill for the energy generated by nuclear fusion in the Sun? In other words, where does the energy pouring out of the Sun come from ultimately?
- 384. Open EndedWhat happens to the positron created during the p-p chain of nuclear reactions inside the Sun?
- 385. Open EndedWhen great currents of hot material rise inside the Sun (and cooler material sinks downward), energy is being transferred by a process known as:
- 386. Open EndedAccording to the formula E=mc2,
- 387. Open EndedWhich part of the Sun has the greatest density?
- 388. Open EndedIn the formula E=mc2, the letter c stands for
- 389. Open EndedIn an earlier era, some scientists suggested that the energy of the Sun comes from meteorites (or, more properly, meteoroids) falling into it and converting their falling motion into heat. Which of the following is part of the argument that shows this mechanism will not work?
- 390. Open EndedThe hotter region directly above the Sun's visible surface is called the
- 391. Open EndedWhich part of the Sun's atmosphere has the lowest density (number of atoms per unit volume)?
- 392. Open EndedA Canadian college student who has taken an astronomy class goes home for the holidays and persuades his parents to let him borrow the family car. When he returns, he finds that his parents are very angry with him, claiming he left the garage door open. Yet he remembers that he carefully closed the garage door with the electronic remote control in the car. After consulting with his astronomy instructor, he comes up with an alternative explanation for why the garage door is open. Which of the following is PART of that explanation?
- 393. Open EndedRecently, some engineers and scientists have proposed building spaceships with enormous "sails" that catch the solar wind and use it to move the ship. What kinds of particles would be hitting this sail (i.e., what is the solar wind mostly made of):
- 394. Open EndedA college friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear energy in the Sun and makes the following observation: "The whole idea of the atomic nucleus is pretty ridiculous. If an oxygen nucleus consists of eight protons and eight neutrons, the charge on that nucleus is positive. Since even I learned in high school that like charges repel, such a nucleus would find all its positive protons repelling and quickly fall apart." How would you answer his argument?
- 395. Open EndedThe process of fusion that keeps our Sun shining begins with which building blocks?
- 396. Open EndedWhich of the following looks the brightest in the sky?
- 397. Open EndedWhen an astronomer rambles on and on about the luminosity of a star she is studying, she is talking about:
- 398. Open EndedA star moving toward the Sun will show:
- 399. Open EndedUsing a good pair of binoculars, you observe a section of the sky where there are stars of many different apparent brightnesses. You find one star that appears especially dim. This star looks dim because it is:
- 400. Open EndedAstronomers arrange the stars into groups called spectral classes (or types) according to the kinds of lines they find in their spectra. These spectral classes are arranged in order of:
- 401. Open EndedStudies of the spectra of stars have revealed that the element that makes up the majority of the stars (75% by mass) is
- 402. Open EndedTwo stars have the exact same luminosity, but star Y is four times dimmer looking that star X. This means that
- 403. Open EndedA star that is quite cool and has a very small radius compared to most stars is called
- 404. Open EndedI am measuring the spectrum of the stars in a spectroscopic binary system. When one of the stars is moving toward the Earth in its orbit, we observe
- 405. Open EndedFor what type of star can astronomers measure the diameter with relative ease?
- 406. Open EndedAn H-R Diagram plots the surface temperature of stars against their:
- 407. Open EndedAstronomers identify the main sequence on the H-R diagram with what activity in the course of a star's life?
- 408. Open EndedStars that do not have what it takes to succeed as a star (i.e. do not have enough mass to fuse hydrogen into helium at their centers) are called:
- 409. Open EndedWhich of the following characteristics of a single star (one that moves through space alone) is it difficult to measure directly?
- 410. Open EndedAfter a lot of work, a group of graduate students has finally measured the wavelengths of many dozens of lines in the spectrum of a distant star. If a number of the lines come from molecules such as titanium oxide, the star is likely to be which spectral type:
- 411. Open EndedTwo stars have the same luminosity, but star B is three times farther away from us than star A. Compared to star A, star B will look
- 412. Open EndedAt an astronomical conference, an astronomer gives a report on a star that interests astronomers because of hints that it may have a planet around it. In his report the astronomer gives the average speed with which this star is moving away from the Sun. How did the astronomer measure this speed?
- 413. Open EndedThe first astronomer who did photometry in a systematic way (even though he did not have a telescope) was
- 414. Open EndedIn recent decades, astronomers discovered stars even cooler than the traditional spectral type M stars recently. Astronomers gave these cool stars a new spectral type, L. If you wanted to go out and find more such type L stars, what kind of instrument would it be smart to use?
- 415. Open EndedWhy can astronomers not measure the diameters of stars directly?
- 416. Open EndedWhat was the first evidence that gravity outside our solar system worked the same way as it does inside?
- 417. Open EndedStars that lie in different places on the main sequence of the H-R diagram differ from each other mainly by having different:
- 418. Open EndedNinety percent of all stars (if plotted on an H-R diagram) would fall into a region astronomers call:
- 419. Open EndedWhich of the following has the smallest mass?
- 420. Open EndedTwo stars that are physically associated (move together through space, gravitationally bound to each other) are called
- 421. Open EndedMeasurements show a certain star has a very high luminosity (100,000 x the Sun's) while its temperature is quite cool (3500o K). How can this be?
- 422. Open EndedThe most likely method for measuring the distance to a star that turned out to be about 30 light years away would be which of the following methods?
- 423. Open EndedIn order for the apparent brightness of a star to be a good indicator of its distance, all the stars would have to
- 424. Open EndedToday, astronomers can measure distances directly to worlds like Venus, Mars, the Moon, or the satellites of Jupiter by
- 425. Open EndedIf an astronomer wants to find the distance to a star that is not variable and is located too far away for parallax measurements, she can:
- 426. Open EndedTo get the distance to a Cepheid variable star, astronomers must take several steps. Which of the following is NOT one of these steps?
- 427. Open EndedThe higher the luminosity (intrinsic brightness) a Cepheid variable is,
- 428. Open EndedA type of star that has turned out to be extremely useful for measuring distances is
- 429. Open EndedAstronomers must often know the distance to a star before they can fully understand its characteristics. Which of the following properties of a star typically requires a knowledge of distance before it can be determined?
- 430. Open EndedWhich of the following is not a place where astronomers believe interstellar dust grains can form?
- 431. Open EndedCosmic rays are
- 432. Open EndedWhich of the following statements about interstellar matter is FALSE?
- 433. Open EndedCosmic rays differ from other forms of interstellar matter by
- 434. Open EndedInterstellar matter refers to:
- 435. Open EndedA star whose temperature is decreasing but whose luminosity is roughly constant moves in what direction on the H-R diagram?
- 436. Open EndedAstronomers call a ball of matter that is contracting to become a star
- 437. Open EndedAstronomers identify the "birth" of a real star (as opposed to the activities of a protostar) with what activity in the star?
- 438. Open EndedIf you want to find stars that are just being born, where are the best places to search?
- 439. Open EndedWhat determines where on the main sequence a star will first plot on the HR diagram?
- 440. Open EndedAstronomers were surprised to find so many Jupiter-mass planets so close to their stars. According to their best theories and models, such "hot Jupiters"
- 441. Open EndedWhich of the following is NOT one of the reasons planets around other stars are so difficult to detect?
- 442. Open EndedTo establish the scale of the solar system, we need to measure the distance to one object orbiting the Sun. Venus was first used for this purpose, but in the 1930's astronomers organized an international campaign to measure the distance to:
- 443. Open EndedWhy can astronomers not tell from what direction a particular cosmic ray started toward the Earth?
- 444. Open EndedThe term "baryon cycle," as astronomers use it, refers to:
- 445. Open EndedThe light element lithium (which, on Earth, is part of medications that improve the lives of people with mental health illnesses) is more common in cosmic rays than it is in the Sun and the stars. What do astronomers think is the reason for this?
- 446. Open EndedSupposing we launched a very fast dart from the Space Shuttle, pointed in some direction away from any planet, so that it could travel beyond the solar system. What would it be most likely to hit first after traveling outward for a while?
- 447. Open EndedAstronomers use the term interstellar matter to refer to:
- 448. Open EndedAstronomers believe that disks of material will form around protostars that are spinning. Which of the following observed phenomena is a good indication of the presence of a disk around a protostar?
- 449. Open EndedA graduate student is given the assignment to find stars with dusty disks around them. What kind of telescope would it be best for her to use for this purpose?
- 450. Open EndedWhich of these stars will take the SHORTEST time to go from the earliest protostar stage to the main sequence?
- 451. Open EndedYou are an astronomy graduate student and you are observing the big Orion Nebula from an airplane that has a good-sized infrared telescope built into it (there really is such a plane.) On an infrared image of the Nebula, what would particularly stand out?
- 452. Open EndedAn astronomer is interested in a galaxy called M31, the nearest galaxy that resembles our Milky Way. It is about 2 million lightyears away. Which technique would be able to give us a distance to this galaxy?
- 453. Open EndedWhy is it so difficult for astronomers to see new stars in the process of birth?
- 454. Open EndedWhich of the following are the small regions that are the embryos of stars (where individual stars are most likely to be born)?
- 455. Open EndedThe luminosity class of a star tells an astronomer
- 456. Open EndedIf an astronomer wants to find and identify as many stars as possible in a star cluster that has recently formed near the surface of a giant molecular cloud (such as the Trapezium cluster in the Orion Nebula), what instrument would be best for her to use?
- 457. Open EndedThe oldest structures in our Galaxy turn out to be
- 458. Open EndedWhich of the following types of stars will spend the shortest time (the greatest number of years) on the main sequence?
- 459. Open EndedWhich of the following stages will our own Sun NOT go through in the future:
- 460. Open EndedThe event in the life of a star that begins its expansion into a giant is
- 461. Open EndedHow long a main sequence star remains on the main sequence in the H-R diagram depends most strongly on
- 462. Open EndedWhy can a star with a mass like our Sun not fuse (produce) further elements beyond carbon and oxygen?
- 463. Open EndedWhen the outer layers of a star like the Sun expand, and it becomes a giant, which way does it move on the H-R diagram?
- 464. Open EndedAs a cluster of stars begins to age, which type of star in the cluster will move off the main sequence of the H-R diagram first?
- 465. Open EndedReally massive stars differ from stars with masses like the Sun in that they
- 466. Open EndedAfter the core of a massive star becomes a neutron star, the rest of the star's material
- 467. Open EndedElements heavier than iron can be created during:
- 468. Open EndedAstronomer have concluded that pulsars are
- 469. Open EndedWhich of the following is a characteristic of degenerate matter in a white dwarf star?
- 470. Open EndedWhich of the following is one reason we do not detect a pulsar in many remnants of supernova explosions?
- 471. Open EndedWhich of the following statements about the life of a star with a mass like the Sun is correct?
- 472. Open EndedWhen a single star with a mass equal to the Sun dies, it will become a
- 473. Open EndedWhen stars become giants, which of the following does NOT usually happen?
- 474. Open EndedOn an H-R diagram of a cluster of stars, which characteristic of the diagram do astronomers use as a good indicator of the cluster's age?
- 475. Open EndedWhich of the following statements about the main sequence stage in the life of a star is FALSE?
- 476. Open EndedBiologists tell us that life on Earth took billions of years to evolve into astronomy students and other examples of intelligent life. If we want to search for planets with intelligent life-forms that evolved over the same period of time that we did, what sorts of stars should we not bother searching around?
- 477. Open EndedWhen a star first begins the long path toward becoming a red giant, a layer of hydrogen around the core begins to undergo fusion. If this layer was too cold to do fusion throughout the main sequence stage, why is it suddenly warm enough?
- 478. Open EndedA white dwarf, compared to a main sequence star with the same mass, would always be:
- 479. Open EndedBecause white dwarfs are small, as their name implies, they are hard to see. What is a way astronomers have to find white dwarfs that distinguishes them from main sequence stars?
- 480. Open EndedAstronomers have noticed that the visible filaments in the Crab Nebula are moving toward us at great speed. How can they know about motions like this?
- 481. Open EndedA member of the college football team wants to weigh as much as possible. Assuming he could somehow survive on all of them, at the surface of which object would he weigh the most?
- 482. Open EndedWhich of the following is NOT a result of supernova explosions?
- 483. Open EndedIn a collapsing star of high mass, when electrons and protons are squeezed together with enormous force, they turn into a neutron and a:
- 484. Open EndedWhich of the following stages can only occur in the life of a low-mass star (whose final mass is less than 1.4 times the mass of the Sun)?
- 485. Open EndedWhy do all stars spend most of their lives on the main sequence?
- 486. Open EndedIn a planetary nebula, the shell of expelled material is glowing intensely. What is the main source of energy for this glow?
- 487. Open EndedA neutron star is as dense as
- 488. Open EndedWhat incident in a massive star's life sets off (begins) the very quick chain of events that leads to a supernova explosion?
- 489. Open EndedIn the model that astronomers have developed for pulsars, why do they suggest that there must be two beams of energy coming from the pulsar?
- 490. Open EndedWhich of the following statements about the Crab Nebula is FALSE?
- 491. Open EndedA group of graduate students, bored during a cloudy night at the observatory, begin to make bets about the time different stars will take to evolve. If they have a cluster of stars which were all born at roughly the same time, and want to know which star will become a red giant first, which of the following stars should they bet on?
- 492. Open Endedactive region
- 493. Open Endedaurora
- 494. Open Endedchromosphere
- 495. Open Endedcorona
- 496. Open Endedcoronal hole
- 497. Open Endedcoronal mass ejection (CME)
- 498. Open Endeddifferential rotation
- 499. Open Endedgranulation
- 500. Open EndedMaunder Minimum
- Answer choicesTagsAnswer choicesTags