Test
Midterm 2
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Preguntas del test (75)
1The Hubble Space Telescope has made many incredible discoveries since its deployment in space. However, a serious problem was discovered shortly after its launch in 1990 that would prevent the telescope from working correctly until a repair mission could be undertaken. The problem that was discovered was that...
- Athe central computer onboard got caught in a loop and kept rebooting - preventing any type of useful research from happening.
- Bthe enormous shaking during launch knocked some of the cameras and detectors out of alignment with the telescope's focal plane and so they could not be used until a repair mission could be sent up to adjust the instruments.
- Cthe solar panels onboard were too small to supply adequate power to all the telescope's systems.
- Dthe super-sensitive high resolution spectrometer attached to the telescope didn't work.
- Ethe telescope's primary mirror was made in the wrong shape so images were out of focus
2Compared to optical telescopes, radio telescopes are built larger mostly due to the fact that
- Aatmospheric turbulence is more of a problem.
- Bthey're less expensive to make than optical telescopes.
- Cradio waves are absorbed to a large degree by the atmosphere.
- Dradio waves have very long wavelengths
- Ecosmic sources giving off radio waves are often very faint
3The James Webb Space Telescope, successor to the Hubble Space Telescope, will have a 6 meter primary mirror composed of 36 hexagonal pieces and will observe the universe from a stable position about 1.5 million km from Earth.
- AVerdadero
- BFalso
4In terms of their design, refractors have certain disadvantages that are not present in reflecting telescopes. Four of the statements below describe these disadvantages. Which of the following is NOT considered a disdadvantage in the design and use of refractors?
- ALenses are subject to chromatic aberration.
- BLenses absorb at least some light, while mirrors don't absorb any.
- CA lens must have two precision surfaces; a mirror needs only one.
- DLenses are harder to focus than mirrors.
- EHeavy lenses, which can only be supported at their edges, tend to deform under their own weight.
5The diagram below illustrates which type of reflecting telescope?
- Aa prime-focus reflector
- Ba Newtonian reflector
- Cnone of these answers are correct
- Da Cassegrain reflector
- Ea Nasmyth-Coude reflector
6Infrared astronomy is most effectly done from mountain-top observatories.
- AVerdadero
- BFalso
7Astronomers use the term _________________________ to describe the effects of atmospheric turbulence on the image that they collect with a telescope.
- A"seeing"
- B"transparency"
- C"clarity"
- D"dispersion"
- E"scatter"
8When a light ray moves into an optically denser material at an angle to the boundary, as shown below, the light ray will...
- Aslow down slightly and bend away from the normal in the denser medium
- Bspeed up slightly and bend toward the normal in the denser medium
- Ctravel straight through unchanged (light rays are not affected by the media that they travel through)
- Dslow down slightly and bend towards the normal in the denser medium
- Espeed up slightly and bend away from the normal in the denser medium
9 The twin Keck telescopes on Mauna Kea have been used to make many discoveries since their commisioning back in the early 1990s. Which of the following is considered to be one of their most important?
- Athe discovery of a liquid water ocean under the crust of Jupiter's moon Europa
- Bthe first direct image of a black hole
- Cthe discovery that the universe is expanding at an ever -accelerating rate
- Dthe first glimpse of the light echoes of the Big Bang
10Nasmyth/Coude reflecting telescopes are used in astronomy primarily because
- Athey can easily accomodate a variety of cameras, instruments and other detection equipment
- Bthey are less expensive to construct and maintain than other designs
- Cthey provide a sharper less-distorted image of celestial objects than other designs
- Dthey are compact in size and easy to transport to dark sky locations.
- Etheir design offers a wide field of view of the sky to the observer/camera/detector
11The Chandra space observatory has made numerous important observations since its launch by NASA in 1999. Which part of the electromagnetic spectrum do its detectors predominantly study?
- AX-ray
- BInfrared
- CMicrowave/Radio
- DGamma ray
- EUltra-Violet
12Over the last 25 years or so, new technology has been steadily developing to significantly improve astronomers' abilities to collect high resolution data at the telescope. This technology is referred to as "adaptive optics". What problem has been corrected by adaptive optics?
- Adefects in the optics of the telescope, such as the correction of the poorly focused Hubble priimary mirror
- Bturbulence in the Earth's atmosphere that creates twinkling
- Cchromatic aberration due to use of only a single lens objective
- Ddegradation of air transparency due to night-time cooling of atmospheric layers
- Ethe opacity of the Earth's atmosphere to some wavelengths of light
13What is the main purpose of a telescope?
- Ato make distant objects appear nearby.
- Bto separate light into its component wavelengths.
- Cto collect a large amount of light and bring it into focus
- Dto magnify distant objects.
- Eto measure the brightness of stars very accurately.
14The design of modern X-ray telescopes depends on
- Athe Cassegrain design, with mirrors made of lead.
- Blenses made of germanium.
- Cachromatic lenses to keep the X-rays in focus
- Dthe prime focus design, with mirrors made of iron.
- Egrazing incidence optics.
15Perhaps the greatest value of radio astronomy to developing our understanding of the universe is
- Athat it allows us to carry out astronomical observations even in daylight hours
- Bthat it allows us to easily study high energy events in space (like exploding stars) which give off high frequencies waves that we would otherwise be unable to study
- Cthat it is in this range of the electromagnetic spectrum where we can gather data of the highest resolution (data with the sharpest details detectable)
- Dthat it allows us to observe objects and events that would otherwise be hidden by intervening clouds of dust and gas (visible light and other waves can't get through)
16In order to deal with the problem of detecting infrared radiation from faint cosmic sources, detectors in telescopes are often isolated in chambers where they continually soak in dry sensitizing hydrogen gas.
- AVerdadero
- BFalso
17In astronomy, an interferometer can be used to
- Aspeed up the processing of CCD images.
- Bdecrease the effects of light pollution in getting darker sky backgrounds.
- Cincrease the sensitivity of infrared telescopes to longer wavelengths.
- Dyield better seeing conditions with optical telescopes.
- Eimprove the angular resolution of radio telescopes.
18Large research telescopes have primary mirrors so big that they tend to sag under their own weight. However, modern technology makes it possible to measure that sag many times each second and apply forces at 100 or more locations on the back of these mirrors to correct their shape and bring all the reflected light into proper focus. This adjustment process is called ___________________.
- AAgile alignment (AA)
- BFlex feedback (FF)
- CFlex response (FR)
- DActive control (AC)
- EAdaptive optical alignment (AOA)
19What is "chromatic abberation"?
- Athe blurring and rapid movement of images at the eyepiece or detector due to small pocket of warm, fast-rising air in the atmosphere
- Bthe phenomenon where light rays of different colour come to a focus at different distances behind a lens, making images blurry in a refracting telescope
- Cthe twinkling effect seen in star images created by air currents within a telescope as it cools down to atmospheric temperature
- Dthe distortion of colours in images at the eyepiece or detector due to high water vapour content in the atmosphere on some evenings
- Ewhen light loss occurs due to poor/damaged coating on mirrors leading to ghostly images in the telescope
20Which of the following telescopes is the largest optical telescope currently in use in the world?
- AThe Giant Magellan Telescope
- BThe Keck II Telescope
- CThe Hobby-Eberly Telescope
- DThe European Extremely Large Telescope (E-ELT)
- EThe Gran Telescopio Canarias
21The first radio telescope purposely created for detecting radio waves from space was built by Grote Reber in 1936.
- AVerdadero
- BFalso
22What is the resolution of a telescope?
- Aits ability to see very faint objects
- Bits ability to make distant objects appear much closer to us
- Cits ability to separate light into its component colors for analysis
- Dits ability to distinguish two adjacent objects close together in the sky
- Eits ability to focus more than just visible light for imaging
23CCD detectors have several advantages in collecting light images at the telescope when compared to using the older technology of photographic film. The most important is that...
- Athey can cover larger areas of the sky than film can.
- Btheir images do not have to be developed as film does.
- Cthey record much more light in a given exposure time.
- Dtheir images never fade, as film can.
- Ethey record colors better than film can.
24The thinner (less curved) that a convex refractor lens is, the shorter its focal length.
- AVerdadero
- BFalso
25What are the factors that determine a telescope's light-gathering ability?
- Athe exposure time (time spent gathering light from a source)
- Bthe total magnification used (the eyepiece that is used with the telescope)
- Cthe collecting area of the optics (total area capable of intercepting and focusing radiation)
- Dthe exposure time and collecting area of the optics
- Ethe exposure time, collecting area of the optics and the total magnification used in the system
26
In which way(s) are the other outer planets in our solar system similar to Jupiter? (see lecture slides - part 1)
1) they rotate on their axis quickly 2) they have many moons
3) they have no solid surface 4) they have magnetic fields that fluctuate wildly in strength- Aanswers 1), 3) and 4)
- Banswers 2), 3) and 4)
- Canswers 1), 2) and 3)
- Danswers 1) and 2)
- Eall answers are true
27 Which of the following asteroids has also been classified as a dwarf planet?
- AItokawa
- BVesta.
- CCeres.
- DEros
- EChiron
28Under the classification system developed by scientists to organize asteroids by composition, a C-type asteroid...(see lecture slides (part 1) for asteroid classes)
- AContains olivine and pyroxene crystals mixed with metals
- BContains a mix of stony silicates along with some iron and/or nickel
- CHas a dense metallic composition of pure nickel/iron
- DHas a chemical composition similar to the Sun, minus the H, He and other volatiles.
29A meteorite is
- Aa streak of light in the atmosphere.
- Ba chunk of space debris orbiting the Earth.
- Can irregularly shaped body, mostly found orbiting between Mars and Jupiter.
- Da chunk of space debris that has struck the ground.
- Ean icy body with a long tail extending from it.
30
In studying the terrestrial planets and icy moons of our solar system, planetary geologists discovered a general sequence of evolutionary stages in many of these bodies (more so in the larger ones). Which of the following sequences indicate this general path of geologic evolution? (See textbook, chapter 14)- Acrust becomes heavily cratered, widespread volcanism, differentiation of layers, possible plate tectonics, mantle solidification
- Bmantle solidification, crust becomes heavily cratered, widespread volcanism, differentiation of layers, possible plate tectonics
- Cdifferentiation of layers, crust becomes heavily cratered, widespread volcanism, possible plate tectonics, mantle solidification
- Dwidespread volcanism, crust becomes heavily cratered, differentiation of layers, mantle solidification, possible plate tectonics
31The observed presence of a comet's tails as well as their size and relative orientation to eachother from the observer's point of view are all influenced by a number of factors. Which of the following in NOT a factor?
- Athe speed at which the comet is traveling
- Bcomet's distance from the Sun
- Cthe inclination of the comet's orbit
- DEarth's relative position and distance to the comet during its inner solar system passage
- Ethe age of the comet (when it was formed)
32Theory suggests that at the end of the collapse phase of our original solar nebula, the compressed fast spinning disk of hot gases, that was to become our solar system, eventually began to cool and condense into solid particles and dust grains. The first such matter to cool and form solid particles was...
- Acarbon- and water-rich silicates
- Bcarbonaceous organic compounds
- Csulfur compounds
- Dnitrogen- and hydrogen-based volatiles
- Emetals and various rock-forming silicates
33There is a class of object in the outer solar system that shares characteristics of both comets and asteroids and that orbits in a zone between the orbits of Jupiter and Neptune. These types of objects also are said to have an unstable orbit because in their motion around the Sun, they cross the orbit of at least one giant planet and consequently occasionally experience a strong gravitational interaction which changes their path. These types of objects are known as ...
- AKBOs
- BNEOs
- CCubewanos
- DCentaurs
- ETNOs
34
Meteorites are classified into three broad groupings based on composition: stones, irons, and stony-irons.- AVerdadero
- BFalso
35 ________________ is the only planet with an average density less than that of water.
- AUranus
- BNeptune
- CJupiter
- DSaturn
36Since the rate of cratering by collisions with small objects has been relatively constant throughout the history of the solar system, counting craters is a method that can be used on any of the solid surface worlds or moons in our solar system for estimating how old the object is.
- AVerdadero
- BFalso
37The first spacecraft to land on the surface of a comet was named
- AGiotto
- BPhilae
- CGalileo
- DDawn.
- EStardust.
38
During the late stages in the formation of our solar system, millions of objects the size of small moons formed, having gravitational fields just strong enough to affect their neighbours. Eventually a few of these bodies grew to become the planets we see today. What do we call them?- APlanetoids
- BKuiper Belt Objects
- CAsteroids
- DPlanetesimals
- EAgglomerated Bodies (ABs)
39Which of the following statements about asteroids is NOT true?
- AMany asteroids in the main asteroid belt belong to different asteroid families that within their groupings share common orbital characteristics and likely common origins.
- BThe first asteroid, 1 Ceres, was discovered by Giovanni Cassini in 1801.
- CAsteroids all revolve about the Sun in the same direction as the planets, and most of their orbits lie near the plane in which Earth and other planets circle.
- DIn the main asteroid belt, the typical spacing between asteroids (down to 1 kilometer in size) is several million kilometers.
- ENASA's Dawn spacecraft, having orbited and studied asteroid 1 Ceres, has discovered that it has (or at one time had) a subsurface ocean of salty water, with occasional eruptions on the surface.
40Objects in the Kuiper belt
- Aare the sources of long-period comets.
- Blie beyond the orbit of Neptune and perpendicular to the ecliptic.
- Corbit in a region from 30 -50 AU from the Sun, and close to the ecliptic.
- Dare dense, like the iron meteorites.
- Eare in random orbits at all inclinations to the ecliptic.
41 All the planets revolve around the Sun in the same direction, except for Venus and Uranus.
- AVerdadero
- BFalso
42
On their inbound journey, comets usually become active and develop a coma while still well beyond the orbit of Jupiter.- AVerdadero
- BFalso
43In the leading theory of solar system formation, the planets...
- Awere ejected from the Sun itself as molten objects that eventually cooled, following a close encounter by the Sun with another star
- Bformed from the same flattened, swirling gas cloud that formed the Sun
- Cformed first, before the Sun, due to the much cooler conditions in the protoplanetary nebula.
- Dbegan forming later than the Sun, after the Sun had already ignited its nuclear burning.
44Radioactive dating of samples taken from bodies from around the solar system indicates that the oldest existing objects (yet found) are...
- Amoon rocks, 4.4 billion years old
- Bcomets dated back to 4.6 billion years old
- Cplanets, such as Mars, where rocks have been dated at 4.6 billion years old
- Dprimitive meteors, about 4.5 billion years old
- Ecarbonaceous asteroids 4.4 billion years old
45What is one good indication that a comet passing near the Sun must be a long-period comet?
- AIt has a longer dust tail than an ion tail
- BIt travels around the Sun in an orbit that lies close to the ecliptic plane
- CIt has a longer ion tail than dust tai
- Drelative to other comets it has a very high velocity when passing the Sun
46The Oort Cloud is believed to be
- Athe circular disk of gas around the Sun's equator from which the planets formed.
- Bthe great nebula found just below the belt stars of Orion
- Ca spherical cloud of cometary nuclei far beyond the Kuiper Belt.
- Da grouping of asteroids and meteoroids between the orbits of Mars and Jupiter.
- Ea flattened belt of cometary nuclei just beyond the orbit of Neptune.
47The Trojan asteroids are found
- Ain orbits that are closer (on average) to the Sun than the Earth's orbit.
- Bin orbits that, on average, are found in the outer solar system between Jupiter and Neptune.
- Csixty degrees ahead or behind Jupiter, sharing its orbit about the Sun.
- Din orbits outside and that never cross Neptune's, with orbital characteristics similar to Pluto.
- Ein the main asteroid belt between Mars and Jupiter - their name comes from their common orbital characteristics and reddish-coloured surfaces.
48What is true about solar system densities?
- APlanetary density increases with increasing distance from the Sun.
- BIn differentiated bodies, the denser materials lie near their surfaces.
- CSaturn has the same density as water.
- DThe denser planets lie closer to the Sun.
- EThe asteroids all have about the same density.
49The nucleus of a comet is typically
- Aa few hundred kilometers across, and bright, shiny white from its ices.
- Bvery durable, made of iron.
- Ca few kilometers in size, and very low in density.
- Da few meters in diameter.
- E1/10 the size of its coma when the comet is active
50The blue-ish ion tail of a comet always points
- Atoward the Sun and disappears at perihelion.
- Bin the direction of the comet's motion.
- Ctoward Earth and never varies.
- Daway from the Sun and becomes longest and brightest at perihelion.
- Eaway from the Sun and disappears at perihelion.
51Without greenhouse gases in its atmosphere to warm it, the Earth's average temperature would be so low that it would be locked in a global ice age.
- AVerdadero
- BFalso
52Studies of crater distribution across the lunar surface show that, typically, there are _________________ craters on the lunar highlands as there are on the lunar maria.
- Ahalf as many
- Bone tenth the
- Cten times the
- Dtwice as many
- Eone hundred times the
53The Earth's tidal bulge (due to the moon's gravitational pull) is directly or indirectly causing the...
1) Moon to very slowly move farther away in its orbit
2) Moon's rotation rate to speed up
3) Earth's rotation rate to slow
4) Moon to very slowly move closer in its orbit- Aonly answer 1) is true
- Bonly answer 4 is true
- Canswers 1) and 3) are true
- Danswers 1) and 4) are true
- Eanswers 3) and 4) are true
54Studies of the chemistry of ancient rocks show that Earth's atmosphere lacked abundant oxygen molecules (free to circulate and be used by large numbers of living creatures) until _________________ years ago.
- A1.6 billion
- B3.1 billion
- C3.8 billion
- D2 billion
- E3.6 billion
55New crust is being added to the Earth's surface in rift zones around the world at an average rate of about 2 square kilometers per year. The added area is enough to completely renew the oceanic crust of the world in ____________________ years. This is a very short period in geological time.
- A50,000
- B100 million
- C100,000
- D1 million
- E500,000
56Three possibilities exist for the original source of Earth’s atmosphere. Which of the following is NOT one of them...
- Athe atmosphere could have been released from the interior through volcanic activity, subsequent to the formation of Earth.
- Bthe atmosphere may have been derived from impacts by comets and asteroids from the outer parts of the solar system.
- Cthe atmosphere may have been created from the slow release of volatiles from ocean surface waters after their interaction with solar UV and X-rays.
- Dthe atmosphere could have been formed with the rest of Earth as it accumulated from debris left over from the formation of the Sun.
57
Most of the following statements describe evidence of similar creatures, plants and geologic features that were discovered on different continents that added support the theory of continental drift. Which of the following was NOT one such piece of evidence? (Hint: see lecture slides [part 2]).- Afossil evidence of the freshwater reptile 'mesosaurs' was found in both southwest Africa and eastern South America
- Brare red sapphires and other unusual gem stones have only been found in mines located along the E coast of Asia and W coast of North America
- Cfossils of specifically-adapted sea creatures called trilobites have been found in both northern Quebec and parts of Scotland, UK
- Dfossils of the prehistoric plant 'glossopteris' were found across a narrow band of all the southern continents
- Emountain ranges of similar shape, age and composition have been found in eastern North America and across northern Europe
58In describing the Earth's interior, scientists say that it is "differentiated". By using this term, they mean that
- Athe Earth's magnetic field varies at different locations on the globe.
- Bthe density increases as you descend downward toward the core.
- Cthe radioactive heating in the core is increasing with time.
- Dthe density of oceanic basalt is less than that of granite on the mountain tops.
- Ethe Earth is very different than any other planet we study.
59
Most of the crust of the moon consists of silicate rocks called anorthosites.- AVerdadero
- BFalso
60On the Moon, the only places where water has been detected in significant amounts are
- Ain thin layers of frost detected in the bowls of craters on the dark (nighttime) side of the moon.
- Bin faint clouds of steam occasionally seen coming from some possibly very weakly active lunar volcanoes.
- Cin the dark streaks in the walls of a few deep craters, which appear to tap ancient briny undergound sources.
- Don the floors of deep craters in the polar regions, as ice deposits that never thaw.
- Ein some shadowed regions in the lunar mare.
61During which of the following lunar phases are the Earth's ocean tides most noticeable?
- Afull moon
- Bfirst quarter
- Cwaxing crescent
- Dwaning gibbous
- Ethird quarter
62Which of the following is NOT a common feature associated with relatively big impact crater formation on the moon?
- Adust rays thrown across the lunar surface
- Bsecondary craters forming from debris thrown out
- C"shocked" rock or "breccia" forming in and around the crater walls
- Descarpments or 'graben' radiating away from the center of the impact
- Ean ejecta blanket
63What is true of spring tides?
- AThe Moon's phase will be first quarter when they occur.
- BThe third quarter moon would be high overhead at dawn when they occur.
- CThe difference between low and high tides would be smallest when they occur.
- DThere would be one high and one low tide each day.
- EThe difference between low and high tides would be greatest of all types.
64Under the surface of a terrestrial planet or other rocky body, temperatures and pressures exerted on different types of rock can be so great that they change the rock type physically and/or chemically. This process is said to produce "_______________" rock.
- Asedimentary
- Bigneous
- Ctransformative
- Dmutatic
- Emetamorphic
65Which combination of gases in the atmosphere are most strongly responsible for the Earth's greenhouse effect?
- Aargon and water vapor.
- Bcarbon monoxide and argon.
- Cmethane and carbon dioxide.
- Dhydrogen and water vapour
- Eargon and carbon dioxide
66The fact that the Earth has a significant magnetic field suggests that
- Athe Earth's interior is similar to Mercury's, as both have fields.
- Ba huge iron meteorite lies somewhere high up in the mantle, not in the core
- Cthe Earth's interior has had time to solidify, with a rigid bar magnet created.
- Dthe Earth's interior must be completely molten to the center.
- Ethe Earth has a liquid metal outer core, spinning rapidly as it rotates.
67Let's say that a big earthquake happens on the exact opposite side of the Earth from us here in Windsor. Geologists at the University of Windsor have a seismograph set up that can detect all the different types of seismic waves that travel away from the epicenter of that quake. Which of following types of seismic vibrations would be able to travel right through the center of the earth to get to the seismograph here in Windsor?
- ATransverse waves
- BS - waves
- CP - waves
- DRayleigh waves
- EShear waves
68When the Apollo astronauts visited the Moon, they left instruments to measure vibrations of the lunar surface caused by geologic activity and/or impacts. Over the years, data collected by these instruments and those of other spacecraft show that lunar moonquakes currently release, on average, about as much energy as...
- Athe Mount St. Helens eruption
- Ba major U.S. city uses in 1 year.
- Cthe most powerful earthquake ever recorded.
- Da firecracker.
- Ean atomic bomb.
69
What is true of the Moon's orbital and rotational periods?- AThe rotational period is longer.
- BThe orbital period is longer.
- CThe rotational period varies with the Moon's phase.
- DThey are equal.
- EThe orbital period is greatest at full moon.
70 Which of the following statements about the Earth/Moon is NOT true?
- Athe Earth's mantle flows through convection ,while the moon's does not
- Bthe Earth generates a significant magnetosphere around it, while the moon has none at all
- Cthe Earth's average density is significantly higher than that of the moon
- Dthe Earth's inner core is about the same temperature as the moon's, just ten times larger.
- Eon average, the Earth's crust is much thinner than that of the moon
71Because of gravitational tidal interactions between the earth and moon, scientists calculate that the earth's rotation is not only slowing down but will begin to rotate in reverse (west to east) in about 2.5 billion years.
- AVerdadero
- BFalso
72
Earth's crustal plates can undergo 4 basic types of interaction at their boundaries. Which of the following is not one of these types of interaction?- Aplates can pull apart from one another at their boundaries
- Bplates can jam together and cause uplifts of crust along the points of contact
- Csmaller plates can flip when the correct pressures are applied by other larger plates
- Done plate can burrow under another when they push into each other.
- Ecrustal plates can slowly slide past one another along their edges
73Which Moon origin theory has the most potential in explaining issues raised by chemical evidence found on the moon?
- ACoformation Theory
- BImpact Theory
- CFission Theory
- DFusion Theory
- ECapture Theory
74Convection in Earth's lower atmosphere is a process that is critical to maintaining conditions suitable for life on its surface. During this process, __________ is/are released into the atmosphere when water vapour condenses. This helps drive the process further along, helps move winds and storms across earth's surface and helps to maintain the convective cycle.
- Aice crystals
- Bozone gas
- Clatent heat
- Dchlorofluorocarbons
- Egreenhouse gases
75The first real study of the Earth's magnetosphere and radiation belts was carried out by the spacecraft named ...
- AVela
- BUhuru
- CExplorer 1
- DSputnik
- EVanguard
Información
- Descripción
- Test sobre Midterm 2 , creado por sara chacon el 13/11/2019.
- Autor
- sara chacon
- Idioma
- English
- Visitas
- 63
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