Extra credit

Harold Washington College, Chicago

Astronomy 201: Descriptive Astronomy

Exam 2- EXTRA CREDIT Spring 2019

Version B ______________________________________________________________________________________________________

Instructions

The exam consists of 60 Multiple-choice questions including 5 Bonus questions.

Read the question and all the answers carefully before choose your answer.

Choose the best answer and mark your answers with a number 2 pencil on a 5-answer scan sheet (only one answer per question).

Try all the questions and make your best effort. Good luck! ___________________________________________________________________________________________________________

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

1) Which of the following lists the planets of our solar system in the correct order from closest to farthest from the Sun?

A) Mercury, Earth, Venus, Mars, Jupiter, Saturn, Neptune, Uranus B) Earth, Mars, Mercury, Venus, Jupiter, Saturn, Uranus, Neptune C) Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune D) Mercury, Venus, Mars, Earth, Saturn, Jupiter, Neptune, Uranus

2) Which of the following is most distant from the Sun? A) a comet in the Kuiper belt B) Eris C) a comet in the Oort cloud D) Pluto E) Neptune

3) A rocky leftover planetesimal orbiting the Sun is A) a meteor. B) an asteroid. C) a meteorite. D) a comet. E) an interstellar object

4) Which planet has the lowest density in our solar system? A) Jupiter B) Uranus C) Mars D) Saturn E) Neptune

Descriptive Astronomy 201 Spring 2019

5) What atmospheric constituent is responsible for the blue color of Uranus and Neptune? A) carbon dioxide B) water C) ammonia D) methane E) hydrogen

6) The wavelength of one of the absorption lines of hydrogen gas observed in a laboratory is 656 nm. You observe several stars and measure the wavelength of this same hydrogen absorption line in each star. Based on the measured wavelength of this line, which star is moving towards the Earth the fastest?

A) 656 nm B) 635 nm C) 640 nm D) 630 nm E) 670 nm

7) Why does a sunspot appear dark? A) The spots are openings which the sun's interior layers can be seen. So it's dark in there! B) A dark sunspot is significantly cooler than the surrounding area on the Sun's surface. C) They are regions that do not emit any radiation. So they are dark! D) A dark sunspot is composed of different elements than the rest of the Sun.

8) Which planet hosts the Galilean moons? A) Neptune B) Mars C) Jupiter D) Saturn E) Venus

9) Which direction does a comet's plasma tail point? A) always almost due north B) straight away from the Sun C) toward the Sun D) perpendicular to the ecliptic plane E) straight behind the comet in its orbit

10) Which planet has the most extreme temperature difference between day and night? A) Mercury B) Venus C) Mars D) Jupiter E) Earth

11) Before New Horizons fly by Pluto, scientists had thought Pluto would be geologically dead, but New Horizons mission showed it has

A) smooth plains most notably a heart shape plain resulting from recent geological activity. B) a very old surface, indicating no geological activity. C) a heavily cratered surface due to giant impacts. D) active volcanoes E) a surface of rock.

12) The Chandra X-ray Observatory must operate in space because A) X-ray telescopes require the use of grazing incidence mirrors. B) X-rays do not penetrate Earth's atmosphere. C) X-rays are too dangerous to be allowed on the ground telescopes. D) NASA didn't like to operate it on ground.

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13) Which of the following statement is true about following spectrums?

Spectrum A

Spectrum B

A) Spectrum A is an absorption spectrum and Spectrum B is a continuous spectrum B) Spectrum A is an emission spectrum and Spectrum B is an absorption spectrum C) Spectrum A is an absorption spectrum and Spectrum B is an emission spectrum D) Spectrum A is an emission spectrum and Spectrum B is an emission spectrum

Use the diagram below to answer Question 14-15. Hydrogen absorption spectral lines of 3 galaxies D, E and G are compared with observed hydrogen spectral lines (F) under laboratory condition.

14) Which galaxy is moving away from the observer? A) Galaxy G only B) Galaxy E only C) Both E and G D) none of them E) Both D and E

15) Which galaxy is moving faster? A) Galaxy G B) Galaxy E C) Galaxy F D) All of them move at the same speed E) Can not determine with this information

16) Planetary rings A) exist around all of the jovian planets. B) are composed of countless ice particles that orbit their planet. C) orbit in the equatorial plane of their planet. D) all of the above

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17) What observational evidence supports the idea that Mercury shrank after it formed? A) the presence of smooth surfaces B) the characteristics of the Caloris Basin C) the presence of many long, tall cliffs D) the presence of many impact craters

18) Which planet has the highest average surface temperature, and why? A) Venus, because of its dense carbon dioxide atmosphere B) Earth, because of its greenhouse effect C) Mercury, because it is closest to the Sun D) Mars, because of its red color E) Jupiter, because it is so big

19) By what process does the Sun generate energy? A) nuclear fusion B) gravitational contraction C) gradual expansion D) nuclear fission E) chemical reactions

20) Which of the following is not a characteristic of the inner planets? A) They have relatively high densities. B) They are smaller than the outer planets. C) Their orbits are relatively closely spaced. D) They have solid, rocky surfaces. E) They have substantial atmospheres.

21) Which of the following best describes the lunar maria? A) frozen oceans of liquid water on the Moon B) relatively smooth, flat plains on the Moon C) mountainous regions on the Moon D) densely cratered regions on the Moon E) region covered by powdery soil on the Moon

22) In what ways is Earth different from the other terrestrial planets? A) Most of its surface is covered with liquid water. B) It has a much higher percentage of oxygen in its atmosphere. C) Life can be found almost everywhere on its surface. D) It is still geologically active. E) All of the above are true.

23) What is the main composition of Uranus and Neptune? A) mostly rocky B) mostly hydrogen and helium C) mostly water D) mostly hydrogen compounds E) mostly nitrogen

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24) The continuous spectra for four stars is shown here. Which star has the highest temperature?

A) star A (green line) B) star B (orange line) C) star D (purple line) D) star C (yellow line)

25) What is Pluto's moon Charon thought to have in common with our own Moon? A) It has the same average density. B) It has the same basic composition. C) It probably formed as a result of a giant impact. D) It has the same approximate mass.

26) Why does Jovian planets have different layers of clouds? A) Clouds form randomly, so on average there are always several layers. B) Layers of clouds are made up of different gases that condense at different temperatures. C) Different gases are present at different altitudes in Jupiter's atmosphere. D) Winds prevent clouds from forming at some altitudes, so we see clouds only at the other altitudes.

27) Which of the following correctly orders the different categories of electromagnetic radiation from shortest to longest wavelength?

A) X-rays, gamma rays, ultraviolet, visible light, infrared, radio B) infrared, visible light, ultraviolet, X-rays, gamma rays, radio C) ultraviolet, X-rays, gamma rays, visible light, infrared, radio D) gamma rays, X-rays, ultraviolet, visible light, infrared, radio E) radio, infrared, visible light, ultraviolet, X-rays, gamma rays

28) Why do asteroids and comets differ in composition? A) Comets are much larger than asteroids. B) Asteroids formed inside the frost line, while comets formed outside. C) Asteroids and comets formed at different times. D) Asteroids formed outside the frost line, while comets formed inside. E) Comets formed from the jovian nebula, while asteroids did not.

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29) Why does Mars have more extreme seasons than Earth? A) because it has a more elliptical orbit B) because it has a much larger axis tilt C) because it is farther from the Sun D) because it has more carbon dioxide in its atmosphere E) all of the above

30) Which of the following is not true of Mercury? A) It has the most extreme temperature difference between day and night due to its slow rotation B) It has long, tall cliffs. C) Its surface is heavily cratered. D) Mercury is the densest planet in the solar system. E) It has no moons.

31) The core of the Sun is A) constantly rising to the surface through convection. B) much hotter and much denser than its surface. C) composed of iron. D) at the same temperature and density as its surface. E) at the same temperature but much denser than its surface.

32) Which moon has the thickest atmosphere, which is made mostly of nitrogen? A) Titan B) Europa C) Ganymede D) Triton

33) What mechanism is most responsible for generating the internal heat of Io that drives its volcanic activity? A) differentiation B) accretion C) bombardment D) tidal heating E) radioactive decay

34) What is the overall composition of the Sun? A) 50 % hydrogen & helium and 50% everything else B) Unknown yet. C) 99% hydrogen & helium and 1% everything else D) nearly equal portions of all the elements such as hydrogen, helium, carbon, oxygen E) 100% hydrogen. Nothing else

35) Where are most of the known asteroids found? A) between the orbits of Jupiter and Saturn B) between the orbits of Mars and Jupiter C) in the Oort cloud D) between the orbits of Earth and Mars E) in the Kuiper belt

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36) What is the Great Red Spot? A) a place where reddish particles from Io impact Jupiter's surface B) a huge impact by shoemaker levy comet on Jupiter's surface C) a region on Jupiter where the temperature is so high that the gas glows with red visible light D) a high-pressure storm on Jupiter E) a hurricane on Uranus

37) Rocks that enter the Earth's atmosphere and blaze a trail all the way to the ground, do not burn up completely and left fragments on ground are known as

A) meteorites B) impacts C) comets D) meteors E) asteroids

38) What causes Jupiter and Saturn to have metallic hydrogen in their interiors? A) high pressure B) presence of heavy metals C) low pressure D) high density E) high temperature

39) Considering only the tilt of their axis, which planet listed below would have the most extreme seasons? A) Jupiter B) Mercury C) Neptune D) Uranus E) Mars

40) Where does nuclear fusion occur in the Sun? A) in the corona B) anywhere below the surface C) in its core D) on the surface (photosphere) E) all of the above

41) A photon with a longer wavelength has A) lower frequency and lower energy. B) higher frequency and higher energy. C) lower frequency and higher energy. D) higher frequency and lower energy. E) There is no simple relationship because different photons travel at different speeds.

42) Rather than being a planet, Pluto is now considered to be a large member of A) the asteroid belt. B) the Kuiper belt. C) an extrasolar planetary system. D) the moon system around Neptune. E) the Oort cloud.

43) What do sunspots, solar prominences, and solar flares all have in common? A) They all occur only in the Sun's photosphere. B) They are all strongly influenced by magnetic fields on the Sun. C) They all have about the same temperature. D) They are all shaped by the solar wind.

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44) Which type of electromagnetic radiation has the highest Energy? A) radio waves B) X-rays C) Gamma rays D) infrared E) ultraviolet

45) Which of the following is NOT a characteristic of the jovian planets? A) They are primarily made of hydrogen, helium, and hydrogen compounds. B) They have rings. C) They have thick atmospheres. D) Their orbits are separated by relatively large distances. E) They have higher density than terrestrial planets.

46) If a hydrogen emission line appears at 656.2 nm in the laboratory, what can we say about a cloud of hydrogen gas with this same emission line at 680.2 nm?

A) It is approaching us. B) The location of the emission line has nothing to do with speed. C) It is neither receding nor approaching us. D) It is receding away from us.

47) In essence, the solar nebular theory states that ________. A) the planets each formed from the collapse of its own separate nebula B) nebulae are clouds of gas and dust in space C) our solar system formed from the collapse of an interstellar cloud of gas and dust D) The nebular theory is a discarded idea that imagined planets forming as a result of a near-collision

between our Sun and another star.

48) What is the origin of the large moons orbiting in the equatorial planes of the jovian planets? A) They are captured comets. B) They were formed by giant impacts. C) They are captured planets. D) They are captured asteroids. E) They were formed by condensation and accretion in a disk of gas around the jovian planet.

49) Which of the following does not have a major effect in shaping planetary surfaces? A) tectonics B) magnetism C) impact cratering D) volcanism E) erosion

50) Rank the five terrestrial worlds in order of size from smallest to largest. A) Moon, Mercury, Venus, Earth, Mars B) Mercury, Moon, Venus, Earth, Mars C) Moon, Mercury, Mars, Venus, Earth D) Mercury, Venus, Earth, Moon, Mars E) Mercury, Moon, Mars, Earth, Venus

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51) According to our theory of solar system formation, what three major changes occurred in the solar nebula as it shrank in size?

A) It got hotter, its rate of rotation increased, and it flattened into a disk. B) Its gas clumped up to form the terrestrial planets, nuclear fusion produced heavy elements to make the

jovian planets, and central temperatures rose to more than a trillion Kelvin. C) It gained energy, it gained angular momentum, and it flattened into a disk. D) Its mass, temperature, and density all increased.

52) Which of the following types of material were condensed into what we call ice beyond the frost line during the formation of planets in the solar nebular?

A) hydrogen and helium B) rocks C) carbon D) hydrogen compounds E) metals

53) Consider an atom of iron in which the nucleus contains 26 protons and 30 neutrons. What is its atomic number and atomic mass number?

A) The atomic number is 30, and the atomic mass number is 26. B) The atomic number is 26, and the atomic mass number is 56. C) The atomic number is 26, and the atomic mass number is 30. D) The atomic number is 30, and the atomic mass number is 56.

54) What is the most volcanically active body in our solar system? A) Io B) Triton C) Titan D) Europa E) Ganymede

55) The average surface temperature of the Sun is about ________. A) 40,000 K B) 5,800 K C) 1,000 K D) 1 million K

56-60 are Bonus questions. Recommend to attempt all Bonus question!

56) Ceres is located in the astroid belt and it is the largest asteroid, but it gets classified as a dwarf planet, Why? A) It orbits inside the frost line. B) It is large enough to be spherical in shape but not large enough to clear its orbit. C) It's composition is similar to Pluto. D) It is larger than Pluto.

57) All of the planets rotate on their axis in the same direction, except Venus and Uranus. According to our theory of solar system formation, how do we explain these exceptions to the general patterns of the planets?

A) Unusual rotations of these planets are the result of giant impacts. B) We can't explain these exceptions with our theory. C) These planets were gravitationally captured by the Sun. D) Venus and Uranus are also rotates in the same directions. No worries!

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58) The graph below illustrate fraction of sunspots covered on Sun's surface. A minimum is shown in 2008. When would you expect the NEXT sunspot minimum to occur?

A) 2119-2120 B) 2025-2026 C) 2019-2020 D) 2014 -2015

59) Which statement is NOT true of all comets in our solar system? A) All comets are leftover planetesimals that originally condensed beyond the frost line in the solar nebula. B) All comets are icy in composition. C) Comets always have dust and plasma tails. D) All comets orbit the Sun.

60) Which of the following is the main reason why Venus has so little wind erosion on its surface? A) its small size B) its slow rotation C) its orbital path D) its thick atmosphere E) its relatively close distance from the Sun

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