Astronomy Practice Questions Chapter 2

What do astronomers mean by a constellation? A constellation is a group of stars related through an ancient story. A constellation is any random grouping of stars in the sky. A constellation is a group of stars that are all located in about the same place in space. A constellation is a region in the sky as seen from Earth.

A constellation is a region in the sky as seen from Earth.

About how many stars are visible to the naked eye on a clear, dark night away from city lights? A few hundred billion A few dozen Several million A couple thousand

A couple thousand

Which of the following correctly describes the meridian in your local sky? A half-circle extending from your horizon due east, through the north celestial pole, to your horizon due west The point directly over your head A half-circle extending from your horizon due east, through your zenith, to your horizon due west A half-circle extending from your horizon due north, through your zenith, to your horizon due south

A half-circle extending from your horizon due north, through your zenith, to your horizon due south

Each choice below describes how a few astronomical phenomena are related to time periods. Which list is entirely correct? (Careful: some lists are partially correct.) Earth's rotation defines a day. The cycle of the Moon's phases takes about a month. Earth's orbit defines a year. Earth's cycle of axis precession takes 26,000 years. Earth's rotation defines a day. The cycle of the Moon's phases takes about a week. Earth's orbit defines a year. Earth's cycle of axis precession defines a month. Earth's rotation defines a day. The saros cycle of eclipses defines a month. Earth's orbit defines a year. Earth's cycle of axis precession takes 26,000 years. Earth's rotation defines a day. The Sun's rotation defines a week. The Moon's rotation defines a month. Earth's orbit defines a year.

Earth's rotation defines a day. The cycle of the Moon's phases takes about a month. Earth's orbit defines a year. Earth's cycle of axis precession takes 26,000 years.

If we have a new moon today, when we will have the next full moon? In about 6 months In about 2 weeks In about 1 week In about a month

In about 2 weeks

What is stellar parallax? It is the slight back-and-forth shifting of star positions that occurs as we view the stars from different positions in Earth's orbit of the Sun. It is the daily rise and set of the stars. It is the change in the set of constellations that we see at different times of year in the evening sky. It describes the fact that stars are actually moving relative to one another, even though to our eyes the stars appear fixed in the constellations.

It is the slight back-and-forth shifting of star positions that occurs as we view the stars from different positions in Earth's orbit of the Sun.

During the time that a planet is in its period of apparent retrograde motion: _________ The planet is getting closer to the Sun in its orbit. Over many days or weeks, the planet moves westward relative to the stars, rather than the usual eastward relative to the stars The planet moves backwards (clockwise as viewed from above Earth's north pole) in its orbit of the Sun. The planet appears to rise in the west and set in the east, rather than the usual rising in the east and setting in the west.

Over many days or weeks, the planet moves westward relative to the stars, rather than the usual eastward relative to the stars

If you are located in the Northern Hemisphere, which of the following correctly describes a relationship between the sky and your location? The altitude of the north celestial pole equals your longitude. The altitude of the celestial equator equals your latitude. The altitude of the north celestial pole equals your latitude. The longitude of the north celestial pole is circumpolar, and therefore crosses your zenith at the meridian.

The altitude of the north celestial pole equals your latitude.

Which of the following statements does not use the term angular size or angular distance correctly? The angular distance between those two bright stars in the sky is about 2 meters. The angular size of the Sun is about the same as that of the Moon. You can use your outstretched hand against the sky to estimate angular sizes and angular distances. The angular distance between those two houses in the distance is 30 degrees.

The angular distance between those two bright stars in the sky is about 2 meters.

What is the celestial sphere? The celestial sphere is a model of how the stars are arranged in the sky relative to our Sun, which is in the middle of the sphere. The celestial sphere is a model that shows the true locations in space of the Sun and a few thousand of the nearest stars. The celestial sphere is a representation of how the entire sky looks as seen from Earth. It represents a belief in an Earth-centered universe, and hence is no longer considered to have any use.

The celestial sphere is a representation of how the entire sky looks as seen from Earth.

Open Hint for Question 5 in a new window What do we mean when we talk about the Milky Way in our sky? The patchy band of light that outlines the plane of the Milky Way Galaxy as seen from Earth. The whitish patch of light we see when we look toward the center of the Milky Way Galaxy. The spiral-shaped galaxy in which we live. The bright stars of the constellations that lie along the ecliptic in our sky.

The patchy band of light that outlines the plane of the Milky Way Galaxy as seen from Earth.

What is the ecliptic? The Sun's daily path from east to west in our sky A half-circle extending from your horizon due north, through your zenith, to your horizon due south The path the Sun appears to trace around the celestial sphere each year The path traced by the Moon's shadow on Earth during a solar eclipse

The path the Sun appears to trace around the celestial sphere each year

What is the saros cycle? The roughly one-month cycle of lunar phases in the sky The annual cycle of the seasons The 26,000-year cycle of the Earth's precession The roughly 18-year cycle over which the pattern of eclipses repeats

The roughly 18-year cycle over which the pattern of eclipses repeats

Which of the following best describes why we have seasons on Earth? The tilt of Earth's axis causes the northern hemisphere to be closer to the Sun than the southern hemisphere in summer, and visa versa in winter. The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year. Earth's elliptical orbit means we are closer to the Sun and therefore receive more intense sunlight at some times of year than at others. The varying speed of Earth in its orbit around the Sun gives us summer when we are moving fastest and winter when we are moving slowest.

The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year.

We cannot see a new moon in our sky because _________. it is obscured by Earth's shadow no sunlight is illuminating the Moon it is above the horizon during the daytime a new moon is quite near the Sun in the sky

a new moon is quite near the Sun in the sky

Lunar eclipses can occur only during a _________. first quarter moon third quarter moon full moon new moon

full moon

We describe a location on Earth's surface by stating its _________. latitude and longitude meridian and longitude latitude and direction altitude and direction (or azimuth)

latitude and longitude

The Moon always shows nearly the same face to Earth because ________. sunlight always hits the same face of the Moon the Moon rotates once in the same amount of time that it takes Earth to orbit the Sun once the Moon rotates once in the same amount of time that it takes the Moon to orbit Earth once the Moon does not rotate

the Moon rotates once in the same amount of time that it takes the Moon to orbit Earth once

The point directly over your head is called _________. the zenith the North Star the north celestial pole the meridian

the zenith