Astronomy Exam #1
Rank the following from longest distance to shortest distance. one light year the distance across our solar system distance from milky way to andromeda distance from earth to alpha centauri distance from sun to center of milky way one AU average distance from Earth to Sun
1. distance from milky way to andromeda 2. distance from sun to center of milky way 3. distance from earth to alpha centauri 4. one light year 5. distance across our solar system 6. average distance from earth to the sun AND one AU
Consider the indicated events in the history of the universe that have helped to make human life possible. Rank the events based on when they occurred, from longest ago to most recent. earliest life on earth earliest humans the universe begins to expand elements such as carbon and oxygen first exist dinosaurs go extinct the big bang nuclear fusion begins in the sun
1. universe begins to expand and the big bang 2. elements such as carbon and oxygen first exist 3. nuclear fusion begins in the sun 4. earliest life on earth 5. dinosaurs go extinct 6. earliest humans
Rank the galaxies from left to right based on the amount of time it has taken their light to travel to Earth, from the longest time to the shortest time: 5 billion light-years 800 million light-years 10 billion light-years 230 million light-years 2 billion light-years 70 million light-years
10 billion light years, 5 billion light years, 2 billion light years, 800 million light years, 230 million light years, 70 million light years
Each of the following figures shows Earth with a different axis tilt. Each also shows a person located in Florida. Rank the figures based on how much time the person spends in daylight during a 24 hour period, from most to least. 0 23.5 to the right 23.5 to the left 90 45
23.5 to the right, 0, 23.5 to the left, 45, 90
Rank the galaxies from left to right based on the age of the universe at the time these galaxies emitted the light we receive from them today, from oldest (closest to today) to youngest (further back in time) 5 billion light-years 800 million light-years 10 billion light-years 230 million light-years 2 billion light-years 70 million light-years
70 million light years, 230 million light years, 800 million light years, 2 billion light years, 5 billion light years, 10 billion light years
Consider the seasonal difference that occurs as Earth orbits the Sun with the different axis tilts. Rank the figures on the basis of the seasonal temperature differences you would expect between summer and winter, from the one with the most extreme seasonal differences to the one with the least extreme. 0 23.5 to the right 23.5 to the left 90 45
90 45 23.5 to the right and 23.5 to the left 0
According to current scientific estimates, when did the Big Bang occur?
about 14 billion years ago
a collection of stars that we make a picture from
asterism
A week after full moon, the Moon's phase is: a. first quarter b. third quarter c. new
b
In reality, the Moon's orbit about Earth is tilted (by about 5 degrees) with respect to Earth's orbit about the Sun. As a result, the actual number of solar eclipses that occur each year is approximately ______. a. 0 b. 2 c. 12 d. 24
b
The term observable universe refers to ___________. a. that portion of the universe that we have so far photographed through telescopes b. that portion of the universe that we can see in principle, given the current age of the universe c. the portion of the universe that can be seen by the naked eye d. the portion of the universe that is not hidden from view by, for example, being below the horizon
b
What conditions must exist for a solar eclipse to occur? a. the only condition is that the phase of the Moon must be new. b. the phase of the moon must be new and the moon must be passing through Earth's orbital plane c. the only condition is that the phase of the moon must be full d. the phase of the moon must be full and the moon must be passing through earth's orbital plane
b
What is really happening in space during the periods when we see Mars going through apparent retrograde motion? a. Mars and the Sun both appear to be in the same constellation as viewed from Earth. b. earth is passing by mars in its orbit around the sun c. earth and mars are moving in opposite directions around the sun d. mars is moving along its orbit in the opposite direction from the way it usually moves
b
As the moon orbits, notice how the astronauts head always points toward Earth. What do we see from Earth that occurs for the same reason? a. we see phases of the moon b. astronauts on the moon sometimes appear to hand upside down c. we see different faces of the moon at different times d. we always see the same face of the moon
d
At what position in the Moon's orbit would we see exactly half of the Moon's daylight face and exactly half of its night face? a. at the two points on the far left and far right b. at the point on the far left c. at the point on the far right d. at the two points at the top and bottom
d
If we wanted to show the Moon's orbit on the scale of this starting frame, we would need to draw a circle that __________ a. has a diameter that is about a quarter of the distance between Earth's orbit and Venus's orbit b. has a diameter that is about half the distance between Earth's orbit and Venus's orbit c. is about twice the size of the white dot representing the sun d. is smaller than one of the green dashes that show Earth's orbit
d
If you could change the layout of the solar system, which of the following would cause a lunar eclipse to occur at least once every month in this hypothetical situation? a. Make the Moon orbit Earth twice as fast. b. Change the Moon's orbital plane so it tilts the opposite way. c. Relocate the Moon to twice its current distance from Earth. d. Change the Moon's orbital plane so it is in the same plane as Earth's orbit around the Sun.
d
On the cosmic calendar, which compresses the history of the universe into a single year, about when did Earth form? a. very early in January b. in mid-February c. in June d. in early September e. in mid-December
d
Suppose that instead of being inclined to Earth's orbit around the Sun, the Moon's orbit was in the same plane as Earth's orbit around the Sun. (Click "Show Moon with flat orbit" to see this situation.) In this hypothetical situation, approximately how many solar eclipses would occur each year? a. 0 b. 1 c. 2 d. 12 e. 24
d
The Andromeda Galaxy is faintly visible to the naked eye. When you look at the Andromeda Galaxy, the retina of your eye is absorbing light that has traveled through space for ________ to reach you. a. about 250 years b. a few minutes c. about 100,000 years d. about 2.5 million years
d
To understand phases of the Moon, you must imagine the view from Earth looking out to the Moon as it orbits. At what position in its orbit would we see all of the Moon's daylight side and none of its night side? a. at the two points on the far left and far right b. at the point on the far right c. at the two points at the top and bottom d. at the point on the far left
d
What conditions must exist for a lunar eclipse to occur? a. the only condition is that the phase of the moon must be new b. the phase of the moon must be new and the moon must be passing through earth's orbital plane c. the only condition is that the phase of the moon must be full d. the phase of the moon must be full and the moon must be passing through earth's orbital plane
d
On the cosmic calendar, which compresses the history of the universe into a single year, about when did early humans first walk on Earth? a. in June b. in September c. in mid-December d. on December 30 e. just a few hours before midnight December 31
e
Suppose we imagine the Sun to be about the size of a grapefruit. How far away are the nearest stars (the three stars of Alpha Centauri)? a. across town b. across the state c. the length of a football field (100 meters) d. 25,000 miles e. across the United States
e
Where along its orbit would the moon also have its daylight side on the right and its night side on the left? a. only at the two points on the far left and far right b. only at the two points at the top and bottom c. only at the point on the far left d. only at the point on the far right e. everywhere along its orbit
e
At most times, Mars appears to move __________ relative to the stars. The exceptions are during its periods of apparent retrograde motion, when Mars appears to move ___________ relative to the stars.
eastward (to the left), westward (to the right)
If you wanted to document the apparent retrograde motion of Mars, you would need to measure and record Mars's ________________ over a period of ______________.
position among the constellations, several months
Rank the objects from left to right based on how much they have aged since they emitted the light we see today, from greatest to least. pluto star on far side of milky way star near center of milky way orion nebula star on near side of Andromeda Galaxy star on far side of Andromeda Galaxy alpha centauri the sun
star on far side of Andromeda Galaxy, star on near side of Andromeda Galaxy, star on far side of milky way, star near center of milky way, orion nebula, alpha centauri, pluto, the sun
Rank the objects on their distances from Earth, from farthest to nearest. pluto star on far side of milky way star near center of milky way orion nebula star on near side of Andromeda Galaxy star on far side of Andromeda Galaxy alpha centauri the sun
star on far side of Andromeda Galaxy, star on near side of Andromeda Galaxy, star on far side of milky way, star near center of milky way, orion nebula, alpha centauri, pluto, the sun
Suppose each object emitted a burst of light right now. Rank the objects from left to right based on the amount of time it would take this light to reach Earth, from longest time to shortest time. pluto star on far side of milky way star near center of milky way orion nebula star on near side of Andromeda Galaxy star on far side of Andromeda Galaxy alpha centauri the sun
star on far side of Andromeda Galaxy, star on near side of Andromeda Galaxy, star on far side of milky way, star near center of milky way, orion nebula, alpha centauri, pluto, the sun
Rank the seasons for the Southern Hemisphere based on Earth's distance from the sun when each season begins, from closest to farthest. winter fall spring summer
summer, fall, spring, winter
Rank the following items according to their size (diameter) from left to right, from largest to smallest. . the local group . the local supercluster . the universe . solar system . the sun . milky way . jupiter . earth
the universe, the local supercluster, the local group, milky way, solar system, sun, jupiter, earth
Rank the seasons for the Northern Hemisphere based on Earth's distance from the Sun when each seasons begins, from closest to farthest. winter fall spring summer
winter, spring, fall, summer
Put the following into perspective: the size of our solar system; the distance to nearby stars; the size of the Milky Way Galaxy; the size of the observable universe. Rank from largest to smallest. The Milky Way Galaxy Distances to nearby stars The observable universe Solar System
The observable universe, milky way galaxy, distances to nearby stars, solar system
Because we live in an expanding universe, distant galaxies are farther away from us today than they were when the light we see from them started on its journey to us. So what do we mean when we say that a galaxy is 7 billion light-years away? a. its light has taken 7 billion years to reach us b. its distance from us has increased by 7 billion light years since its light started its journey to us c. it is 7 billion light-years away today d. it was 7 billion light-years away when its light started its journey to us
a
Beijing and Philadelphia have about the same latitude but very different longitudes. Therefore, tonight's night sky in these two places: a. will look about the same. b. will have completely different sets of constellations. c. will have partially different sets of constellations.
a
Could we see a galaxy that is 50 billion light-years away? a. no, because it would be beyond the bounds of our observable universe b. no, because a galaxy could not possibly be that far away c. yes, if we had a big enough telescope d. none of the above
a
If there is going to be a total lunar eclipse tonight, then you know that: a. the Moon's phase is full b. the Moon's phase is new c. the Moon is unusually close to Earth
a
In winter, Earth's axis points toward the star Polaris. In spring: a. the axis also points toward Polaris b. the axis points toward Vega c. the axis points toward the Sun
a
Notice how the arrows representing the Sun's rays are at first spread apart but become parallel as the video zooms in on the Moon's orbit. Why do the Sun's rays become parallel at the end of the video? a. the sun is so far away compared to the size of the Moon's orbit that all the rays reaching the orbit come from essentially the same direction b. the video is incorrect; the Sun's rays actually converge on the Moon from all directions, not just as parallel rays c. the rays that reach Earth and the moon come from only one very small spot on the sun d. rays from the sun that start out going in different directions turn toward Earth as they travel away from the sun
a
Suppose we observe a galaxy that is 13 billion light-years away. Which of the following can we conclude? a. the galaxy formed before the universe was 1 billion years old b. we see the galaxy as it looked when it was 13 billion years old c. the galaxy is older than the Milky Way d. we see the galaxy as it looked when it was 1 billion years old
a
The North Celestial Pole is at 35.0 degrees above your northern horizon. This tells you that: a. you are at latitude 35.0 degrees north b. you are at longitude 35.0 degrees east c. it is the winter solstice
a
The fact that nearly all galaxies are moving away from us, with more distant ones moving faster, helped us to conclude that: a. the universe is expanding b. galaxies repel each other like magnets c. our galaxy lies near the center of the universe
a
The fact that we always see the same face of the Moon tells us that a. the Moon's rotation period is the same as its orbital period. b. the Moon looks the same on both sides. c. the Moon does not rotate. d. the Moon's rotation period is the same as the Earth's rotation period.
a
The star Betelgeuse is about 600 light-years away. If it explodes tonight, a. we won't know about it until 600 years from now b. we'll know it immediately because it will be brighter than the full moon in the sky c. we'll know because debris from the explosion will rain down on us from space d. none of the above
a
What do astronomers mean by the Big Bang? a. the event that marked the beginning of the expansion of the universe b. a gigantic explosion that blew all the galaxies in the universe to smithereens c. the explosion of a massive star at the end of its life d. the event that marked the birth of our solar system
a
When it is summer in Australia, the season in the United States is: a. winter b. summer c. spring
a
When we see Saturn going through a period of apparent retrograde motion, it means: a. Earth is passing Saturn in its orbit, with both planets on the same side of the Sun. b. Saturn is temporarily moving backward in its orbit of the Sun. c. Saturn and Earth must be on opposite sides of the Sun.
a
Where is our solar system located within the Milky Way Galaxy? a. roughly halfway between the center and the edge of the visible disk of the galaxy b. at the far edge of the galaxy's visible disk c. very near the center of the galaxy d. in the halo of the galaxy
a
Which statement best describes how variation in the Earth-Sun distance affects the seasons? a. the variation in Earth-Sun distance over the course of each year has virtually no effect on the seasons b. Summer occurs when Earth is closer to the Sun and winter occurs when Earth is farther from the Sun c. No matter where you live or what the seasons, it is generally hotter when Earth is closer to the Sun and colder when Earth is farther from the sun
a
an astronomical unit is: a. Earth's average distance from the sun b. any large astronomical distance c. any planet's average distance from the sun d. none of the above
a
which of the following correctly lists our "cosmic address" from small to large? a. Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe b. Earth, solar system, local group, local supercluster, milky way galaxy, universe c. Earth, milky way galaxy, solar system, local group, local supercluster, universe
a
You've now seen that Earth's varying distance cannot be the cause of our seasons. So what is the cause of the seasons? a. Earth's speed varies in its orbit around the Sun, giving us summer when Earth is moving fastest and winter when Earth is moving slowest b. The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year c. the seasons are caused by variation in the amount of rainfall (or snowfall) in different places at different times of year d. The tilt of Earth's axis causes the northern hemisphere to be closer to the sun than the southern hemisphere is summer, and vice versa in winter
b
Consider a time when Mars is in the middle of one of its periods of apparent retrograde motion. During this time, Mars appears _________ in our night sky and crosses the meridian around ________.
brightest, midnight
According to current scientific estimates, when did the Big Bang occur? a. about 65 million years ago b. about 4.5 billion years ago c. about 14 billion years ago d. about 10 billion years ago e. about 20 billion years ago
c
In what sense are telescoped like time machines? a. they allow us to look at a galaxy and see it as it was at many different times in the past b. they allow us to see distant objects as they will be in the future c. they allow us to see distant objects as they were long in the past d. they allow us to see what Earth looked like long ago
c
On the cosmic calendar, which compresses the history of the universe into a single year, about when did life arise on Earth? a. in late January b. in mid-August c. in September d. in mid-December e. just a few hours before midnight on December 31
c
Our solar system consists of: a. a few hundred billion stars, bound together by gravity b. the sun and the planets, and nothing else c. the Sun and all the objects that orbit it d. the Sun and several nearby stars, as well as the planets and other objects that orbit these stars
c
Suppose that someone in the Andromeda galaxy had a super-telescope through which they were looking at Earth right now. They would see Earth _______________. a. as it was about 100,000 years ago b. as it is right now c. as it was about 2.5 million years ago d. as it will be about 2.5 million years from now
c
The Sun-centered system pictured in the lower window of the video offers a simple explanation for observations of apparent retrograde motion. Should these facts alone have been enough to convince the ancient Greeks that Earth really does go around the Sun? a. Yes, but the Greeks did not realize it because they never even considered a Sun-centered model. b. Yes, but the Greeks were unable to detect apparent retrograde motion and therefore didn't know that it ruled out an Earth-centered universe. c. No, because the Greeks had an Earth-centered model that also accounted for apparent retrograde motion. d. No, because apparent retrograde motion still happens in an Earth-centered system as the Sun passes by a planet in its orbit around Earth.
c
Two stars that are in the same constellation: a. must both be part of the same cluster of stars in space b. must both have been discovered at about the same time c. may actually be very far away from each other
c
What do astronomers mean by the Big Bang? a. the explosion of a massive star at the end of its life b. a gigantic explosion that blew all the galaxies in the universe to smithereens c. the event that marked the beginning of the expansion of the universe d. the event that marked the birth of our solar system
c
Which of the following best describes what we mean by the universe? a. a vast collection of stars that number as many as the grains of sand on all the beaches on Earth b. all the galaxies in all the superclusters c. the sum total of all matter and energy d. our Milky Way Galaxy
c
