ASTRONOMY 101
Mesa College
Fall 2002
Third Examination
NAME______________________________(Print) Lec. hr.______ days class meets______
1 Most comets
a. have periods greater than 200 years
b. have periods less than 200 years
c. bring bad tidings
2 Theories on the formation of asteroids include
a. they are moons stripped from the planets
b. they are the debris of many comets
c. they are the debris of differentiated object that broke up
3 The theory that the planets formed from a disc around the sun explains why
a. the Earth has a moon
b. comets are mostly in the Oort comet cloud
c. meteors often come from objects in retrograde orbits
d. major and minor planets orbit the sun in the same direction
4 Studying crystals in iron-nickel meteorites enables us to determine that these meteorites were
a. once fairly hot and cooled very slowly d. formed near the surface of an asteroid
b. formed beyond the orbit of Jupiter e. often in retrograde (clockwise) orbits
c. once very cold and warmed up very slowly
5 Black spots are occasionally seen on the surface of the Sun. The scientific technical term for these is sunspots. If we observe these sunspots over a long period of time, what would we notice?
a. The same spots persist, and as far as we can tell have existed since the Sun formed.
b. These spots only occur on the northern hemisphere of the Sun.
c. Sunspots exist for at most one day.
d. Sunspots are tranquil places in the solar atmosphere, and are removed from regions associated with solar flares.
e. The number of sunspots increases and decreases in a cycle with a period of 11 years.
6 The particle in space called a _______ passes through Earth's atmosphere, heats up, and glows. It is then called a ________. Finally, when the particle reached the surface of Earth, it is called a _______.
a. meteoroid, meteor, meteorite
b. meteor, meteorite, meteoroid
c. meteorite, meteor, meteoroid
7 The tail of a comet
a. points towards the sun d. follows the comet
b. points away from the sun e. precedes the comet
c. points towards the Earth
8 Meteorites are thought to be fragments of larger bodies that collided in space and broke up.
a. true b. false
9 Some meteor showers are associated with the orbital paths of comets.
a. true b. false
10 The basic difference between a meteor fall & a meteor find is
a. is that a fall fell from the sky & a find was always on the Earth.
b. is that a fall was seen to fall from the sky & a find was found many years after it fell to Earth.
c. both these terms mean the same thing.
11 A meteor shines by which one of the following?
a. By becoming heated by entering the earth's atmosphere
b. By light reflected from nearby stars
c. By reflected sunlight
d. By light reflected from the Earth
e. By heat generated in its orbit around the sun
12 The largest asteroid is
a. smaller than moon
b. larger than Mercury but smaller than Jupiter
c. larger than Jupiter
13 The composition of an asteroid is most like
a. a comet b. a Jovian planet c. a rock
14 The Trojan asteroids are found to be in orbits
a. between Mars & Jupiter c. with Jupiter
b. beyond Pluto d. about the Earth
15 Which has the least mass?
a. Earth b. Moon c. Sun d. comet
16 The solid part of a comet is made mostly of
a. iron c. helium
b. ice d. rock
17 Comets often have two tails.
a. true b. false
18 Most of the asteroids revolve about the sun between the orbits of
a. Jupiter and Saturn c. Mars and Jupiter
b. Earth and Mars d. Saturn and Uranus
19 Large loops or protrusions of hot material extending hundreds of thousands of kilometers above the edge of the visible disk of the sun are called
a. flares d. prominences
b. spicules e. superspots
c. plages
20 The layers of the sun's atmosphere from the innermost to the most distant are
a. chromosphere, corona, photosphere
b. photosphere, chromosphere, corona
c. corona, photosphere, chromosphere
d. chromosphere, photosphere, corona
21 The Sun rotates once on its axis approximately once every
a. day b. month c. year
22 Which of the following is the more violent phenomena found on the Sun?
a. sunspots b. granules c. flares d. prominences
23 The maunder minimum is
a. followed after 11 years by a maunder maximum
b. a period when the least number of maunders can be observed on the solar disk
c. the period during magnetic field reversal when the solar magnetic field is at a minimum
d. an extended period of low solar activity
e. the region of coolest temperature in the vicinity of a sunspot
24 The temperature at the sun's surface(photosphere) in K is about
a. 600 c. 100,000
b. 6,000 d. 1,000,000
25 Coronal holes are thought to be the source of
a. the solar wind c. sunspots
b. flares d. magnetic storms
26 The solar wind consists of
a. charged atomic particles, mostly protons and electrons
b. X-ray and ultraviolet radiation
c. air currents generated by thermal conductivity
d. radio radiation
27 The most abundant element in the sun is
a. hydrogen b. nitrogen c. helium d. iron
28 Sunspots are considerably cooler than the rest of the photosphere.
a. true b. false
29 Sunspots
a. are not accompanied by detectable magnetic effects
b. occur in cycles with an average length of 5 years
c. are regions which have a strong magnetic field
30 The Sun obtains its energy from
a. nuclear fission reactions on the solar surface.
b. nuclear fusion reactions in its core.
c. the conversion of gravitational potential energy to heat energy.
d. extremely explosive chemical reactions.
e. the process of magnetic re-connection.
31 The binding energy of an atom is:
a. the amount of energy used to fuse hydrogen atoms together
b. the amount of energy an atom has relative to the hydrogen atom
c. the energy required to completely separate the particles in the nucleus of an atom
d. none of the above
32 Of the following spectral types, which is the hotter?
a. B b. M c. G d. K
33 The proper motion of a star is the
a. rate the star is moving in space in units of km/sec.
b. the speed at which the star is approaching us in km/sec.
c. the rate, in sec of arc per yr, appears to be moving across the sky.
34 The absolute magnitude is defined as how bright the star would appear if it were at a distance of 10 pc(32 LY).
a. true b. false
35 The color index of a nearby star is essentially a measure of the star's
a. luminosity d. mass
b. surface temperature e. composition
c. size
36 A binary star system that is identified because of a change in brightness due to one star of the system passing in front of the other is classed as a(n)
a. visual binary c. spectroscopic binary
b. eclipsing binary d. astrometric binary
37 The typical star in space is one that is
a. hot and emits tremendous amount of energy, compared to the Sun
b. like the sun
c. cool and emits smaller amounts of energy than the sun
38 If star A has a larger proper motion than star B, star A is probably
a. more distant from us than star B
b. nearer to us than star B
39 A study of a star's spectrum allows the determining of
a. elements present d. all of the above
b. temperature e. none of the above
c. radial velocity
40 In which portion of the Hertzsprung-Russell diagram, as it is usually presented, do we find stars of the lowest average density?
a. upper left corner c. upper right corner
b. center of main sequence d. lower left corner
41 In which portion of the Hertzsprung-Russell diagram, as it is usually presented, do we find stars of the highest average density?
a. upper left corner c. upper right corner
b. center of main sequence d. lower left corner
42 Stars on the Main Sequence produce their energy from
a. fusion of carbon into iron c. fusion of He into carbon
b. gravitational energy d. fusion of H into helium
43 In studying the sun, is assumed that the inward force of gravity is balanced by the forces that arise from gas and radiation pressure.
a. true b. false c. since we don't know, no assumption is made
44 The normal maximum mass for a star has been determined to be about_________ solar masses.
a. 10 c. 5
b. 17.5 d. between 50 and 100
45 The minimum mass for a star has been determined to be about _________ solar masses.
a. 10 b. 1 c. .05 d. .00001
46 Convection is the process of transporting energy by
a. photons traveling at the speed of light
b. the movement of hotter matter from one location to another
c. the vibrations of adjacent atoms
47 At present, the observed neutrino flux emanating from the sun is ________ the amount predicted by present theory.
a. less than b. more than c. exactly
48 As a general statement, a more massive star produces ________ energy than a less massive star.
a. more b. less
In the HR-Diagram below label the following regions. 3 points
main sequence, white dwarf, & giant
Describe how visual binaries are discovered. 2 points
Describe the mode of energy transport known as radiation. give one example 2 points
Give two of the possible fates of a comet. 2 points
1
2
Describe how spectroscopic binaries are discovered. 2 points
Describe the mode of energy transport known as conduction. give one example 2 points
Describe the Zeeman(splitting) Effect. 2 points
Why do protons resist being squeezed together? 2 points
List two characteristics about a star that cam be determined by examining a star's spectrum.
2 points
1
2
Describe the surface, size, & shape of the two satellites of Mars. 3 points
Describe the basic formation of the Solar System. Note: the question not about the form but the formation of the Solar System. 3 points
Describe two basic characteristics of the elementary particle known as a neutrino. 2 points
1
2
We believe that comets do crash into planets from time-to-time, but have we ever observed this happen? 1 point
Describe the possible effects of solar flares on the Earth or the region just above the surface. 2 points
With a drawing show the 5 basic parts of a comet. Be sure to label each of the 5 parts. 5 points
Name the three basic type of meteorites based on chemical composition & give there chemical makeup. 3 points
1____________________ _________________________________
2____________________ _________________________________
3____________________ _________________________________
Describe the phenomena known as photospheric granulation. 2 points
Describe how spectroscopic binaries are discovered. 2 points
Why do protons resist being squeezed together? 2 points
Describe the mode of energy transport known as conduction. give one example 2 points
In the HR-Diagram below label the following regions. 3 points
main sequence, white dwarf, & giant
Describe two basic characteristics of the elementary particle known as a neutrino. 2 points
1
2
Describe the possible effects of solar flares on the Earth or the region just above the surface. 2 points