ASTRONOMY 101

Mesa College

Fall 2002

Second Examination

NAME______________________________(Print) Lec. hr.______ days class meets______

1 The giant planets are made up of mostly

a. Iron & Oxygen c. Nitrogen & Oxygen

b. Lead d. Hydrogen & Helium

2 The motion of the planets around the sun seems to indicate that

a. they were most likely captured at random by the sun

b. they most likely were formed by a close encounter of two stars

c. they were formed in a uniform process as a part of the sun's formation

3 The average density of the Jovian planets is

a. greater than the terrestrial planets

b. less than the terrestrial planets

c. the same as the terrestrial planets

4 Of the listed planets, which is the most distant from the sun?

a. Mars c. Pluto

b. Saturn d. Uranus

5 The Van Allen radiation belt consists of

a. trapped photons

b. charged particles trapped in the earth's magnetic field

c. the Aurora

d. micrometeorites trapped in the earth's magnetic field

6 Have asteroidal impacts had a drastic effect on some life forms found on the Earth?

a. yes b. no

7 The earth's atmosphere acts like a "greenhouse" to trap in thermal energy.

a. true b. false

8 The nature of the earth's deep interior is judged from

a. drilling projects in the bottom of the ocean

b. earthquake wave studies

c. explosive blasts

d. none of these

9 The layer of atmosphere which contacts the earth's surface is the

a. ionosphere d. troposphere

b. stratosphere e. eosphere

c. mesosphere

10 The diameter of the earth is approximately (in miles)

a. 4,000 d. 25,000

b. 8,000 e. one-half the distance to the moon

c. 160,000

11 The inner core of the earth is thought to be mainly made up of

a. iron and nickel b. silicates c. solid hydrogen

12 The outer core of the earth is thought to be

a. solid b. liquid

13 Today the Earth's atmosphere is made mainly of

a. ammonia d. methane

b. oxygen e. nitrogen

c. carbon dioxide

14 The Earth's magnetic field is believed to result from

a. iron deposits in the Earth's crust

b. a permanent magnet in the Earth's solid iron core

c. a churning motion in the rotating liquid metallic core of the Earth

d. the motion of plates of the Earth's crust

e. electrical flows driven by the solar wind

15 Sedimentary rocks are

a. made up of fragments of igneous or living organisms, deposited by wind or water and cemented together without melting.

b. rocks formed from cooled molten volcanic material.

c. formed by high temperature and pressure from other types of rocks.

16 The movement of the continental plates is cause by

a. strong winds c. earthquakes

b. volcanoes d. convection currents in the mantle

17 Analysis of lunar soil samples shows

a. the maria, or at least the Sea of Tranquility and the Ocean of Storms, were once great seas

b. lunar craters are all remnants of extinct lunar volcanos

c. the lunar atmosphere is composed primarily of oxygen

d. there is no evidence of indigenous water ever having been present on the moon

e. rills are old river beds on the moon

18 The light streaks that radiate from some young lunar craters are known as

a. rays d. highlands

b. rills e. craters

c. volcanos

19 Of the three theories of the origin of the moon, which is the one that is generally accepted?

a. condensation c. capture

b. fission d. giant impact

20 Compared to the Earth, the mean density of the moon

a. greater b. less c. the same

21 About 1/3 of the moon is made up of a liquid iron core.

a. true b. false

22 The large, circular, smooth areas on the moon which look relatively dark, due to their low reflectivity, are called

a. maria d. mountains

b. craters e. highlands

c. rills

23 The great majority of craters on the Moon are attributed to which of these causes?

a. volcanic action

b. "moonquakes"

c. bubbles which burst when the Moon was molten

d. explosions of impacting bodies

24 It is believed that Mercury has an unusually large percentage of its mass in the form of an iron core.

a. true b. false

25 Mercury is now known to have a strong magnetic field.

a. true b. false

26 Mercury has a high surface temperature because of its

a. strong greenhouse effect c. nearness to the sun

b. rapid rotation d. eccentric orbit

27 Mercury's period of rotation was deduced from

a. visual observations of the Mercurian mountains as they appear to move across the planet's disk

b. careful timing of the instants of maximum western elongation

c. observation of surface features on the planet with the aid of the Voyager I

and II spacecraft

d. radio observations of the planet

28 The surface of Mercury has been found to have all but

a. maria like features c. active volcanos

b. craters d. scarps

29 Triton, the satellite of Neptune

a. has a surface that appears very similar to that of our Moon

b. has a mass that is almost equal to that of Saturn

c. has an Earth-like atmosphere

d. has a very unusual surface the includes ice "volcanoes" and revolves about Neptune in a clockwise fashion.

30 The fact that Pluto has been found to possess a moon means that

a. it is now closer to the Sun than Neptune

b. the mass of the system (Pluto and its moon) can accurately be

determined

c. the hypothesis that Pluto is an escaped satellite of Neptune is confirmed

d. Pluto is definitely a terrestrial-type planet

e. Pluto is almost certainly a spent comet nucleus

31 Of the planets listed, which two are most similar to each other?

a. Earth & Jupiter c. Pluto & Saturn

b. Mars & Pluto d. Uranus & Neptune

32 Jupiter radiates a slight excess of energy over that which it is expected to radiate. We can explain this most logically if we assume that

a. Jupiter is on fire

b. Jupiter is being heavily bombarded by meteors

c. Jupiter still contains heat leftover from its formation

d. Jupiter is preparing to leave the solar system

33 A large canyon is known to be on the surface of Mars.

a. true b. false

34 Mars' polar caps are thought to be made up of:

a. only water ice

b. only CO₂ ice

c. a mixture of water and CO₂ ices

35 Uranus is known to have a ring system.

a. true b. false

36 The white bands of clouds that can be seen in the atmospheres of Jupiter and Saturn, even with a small telescope, are made up of:

a. methane b. hydrogen c. helium d. ammonia

37 The atmosphere of Titan is primarily

a. methane c. ammonia

b. hydrogen d. nitrogen

38 The Viking Lander experiments proved that life existed in the past on Mars/

a. true b. false

39 Of the planets listed, which has the strongest magnetic field?

a. Earth c. Pluto

b. Neptune d. Jupiter

40 During the flybys of the Voyager spacecraft, which of the Galilean satellites was observed to have volcanoes erupting on its surface?

a. Io c. Europa

b. Ganymede d. Callisto

41 The earth's crust is

a. as thick as its mantle

b. much thinner than the mantle

c. the same thickness as the core

42 A faint ring has been discovered around Jupiter.

a. true b. false

43 The mass that makes up Jupiter is mostly

a. solid b. liquid c. gas

44 The great red spot on Jupiter is thought to be

a. a blemish d. a hurricane or storm-like feature

b. a volcano e. a pool of rust

c. a large caldera

45 Which planet has the hottest surface?

a. Pluto b. Mars c. Venus d. Earth

46 Radar maps of Venus are interpreted to show

a. impact craters c. both of these

b. volcano craters d. neither of these

47 The principal content of Venus' atmosphere is

a. carbon dioxide d. hydrogen fluoride

b. nitrogen e. sulfuric acid

c. oxygen

48 The rings of Mars were discovered

a. by the Voyager II spacecraft

b. when the planet passed in front of a star that blocked out the

starlight (by Earth-based telescopes)

c. by the Pioneer 10 spacecraft

d. (it does not have a ring system)

49 The rings around Saturn are

a. believed to be the remains of an escaped moon of Jupiter

b. likely to dissipate within the next century

c. about 1 A.U. thick and nearly 100 A.U. across

d. likely myriads of solid particles each orbiting the planet

e. no doubt a solid ice formation, rotating about the planet like a wheel

50 Which surface can be assume to be the younger surface?

a. a surface with a high crater density

b. a surface with a low craters density

Describe the basic theory for the formation of the Solar System. Be sure to describe the most important points. 3 points

Describe the phenomena known as the "Greenhouse Effect". 2 points

Describe how scientists determine the internal structure of the Earth and answer such questions as "is the outer core in a solid or liquid state". 2 points

What are the two most abundant elements that make up the lower atmosphere of the Earth? 2 points

Describe the general appearance of the surface of Mercury as seen from a low altitude satellite orbiting Mercury. Three features 3 points

Describe at appearance of Callisto(satellite of Jupiter), as seen by a satellite located near this moon. 2 points

Describe the Fission Theory for the formation of the moon. 2 points

Discuss why the Moon lacks an atmosphere. 2 points

Describe at appearance of Io(satellite of Jupiter), as seen by a satellites located near this moon.

2 points

Describe the Capture Theory that is used to suggest the origin of the Moon. 2 points

Describe the modern model of Jupiter's interior. There are 4 layers. You may, if you wish use a labeled drawing. 4 points

Why isn't the Earth covered with craters as the Moon is? 2 points

Describe at appearance of Titan(satellite of Saturn), as seen by a satellite located near this moon. 2 points

Describe three features found on the surface of Mars. 3 points

Describe how Pluto was discovered. Don't give a partial answer, state the "whole" story. 3 points

Describe at appearance of Triton(satellite of Neptune), as seen by a satellite located near this moon. 2 points

What is the evidence that at one time great amounts of water flowed on the surface of Mars?

2 points

Discuss how the surface of Venus would appear if you could see through its clouds. 2 points

What is the possible cause, discussed in class, of why Uranus' rotational axis is approximately 90 degrees. 2 points

Describe the appearance of Mars as seen from telescopes on the Earth. (three characteristics)

3 points.

Describe the lunar features known as mountain ranges and where they are found on the surface.

2 points

Describe the lunar environment, including temperature extremes, surface gravity, & atmosphere(if any). 3 points

What is meant when we say a planet is still differentiating. 2 points

Describe how Mars appears in a Earth-based telescope. Describe 3 features. 3 points

Why can't liquid water exist on the surface of Mars today? 2 points

Which is older, the maria or the highlands of the moon? What observations of the surface with a telescope would lead you to your conclusion? 2 points

How does nature produces igneous rocks. 2 points