Review exam 1 Solutions.
ANSWERS OF REVIEW QUESTIONS:
Earth rotates toward the east, from left to right in Figure 1-4 (note that you can
identify the Baja peninsula and Southern California).
This is because earth rotates
counter clockwise from the point of view of looking down at the north pole.
turns from left to right in the image, the land will be carried from daylight into
darkness; thus the boundary is the sunset line that separates afternoon from evening
Our solar system is the collection of gas, dust, and larger bodies gravitationally bound
to the sun.
This includes the sun, all planets and their satellites, asteroids, comets,
and the gas and dust found in interplanetary space.
The primary constituents of the
solar system are the sun, planets and comets.
Our galaxy on the other hand is
primarily composed of stars, and clouds of gas and dust known as nebulae.
galaxy is held together by the mutual gravitational attraction of the gas, dust, and stars
The universe is the collection of all matter.
Anything that has mass or
energy is part of the universe, whether we can observe it our not.
Seeing planets around other star systems is very difficult for three reasons.
will appear as point sources.
Planets are smaller in radius than the stars they orbit,
but at the same distance.
Hence their angular diameter would be even smaller.
Second, the planets will also be much fainter than the stars they orbit.
received from a planet is light from the star that reflects off the planet's surface.
planet's surface probably isn't perfectly reflecting and is smaller in size than the star;
therefore, the light from the planet will be much fainter than that from the star.
Finally, we are trying to look for this very faint light from the planet right next to the
much brighter light from the star, making the planet even more difficult to notice.
The Milky Way is a faint grayish band of light that forms a circular path across the
It is something that can be easily observed from Earth.
The Milky Way
galaxy is a collection of about 10
stars that contains a well-defined disk with a spiral
nature and an extended halo.
All of the stars visible to the naked eye are part of the
Milky Way Galaxy, but they are not necessarily part of the Milky Way.
are three objects visible to the naked eye that aren’t part of the Milky Way galaxy,
these are the Andromeda Galaxy, the Large Magellanic Cloud, and the Small
10. The object pictured is a galaxy.
All galaxies contain stars and planets.
also shows well defined spiral arms.
Galaxy clusters are groups of galaxies that are
bound together by their mutual gravitation, and filaments are large strings of galaxy
So the galaxy pictured contains stars, planets, and spiral arms, and could be
contained within a galaxy cluster and filament.