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ASTR 102 Exam Questions with 100% Correct
Answers | Updated &Verified | | 100% Score
What are the Milky Way Galaxy's spiral arms? -
.....ANSWER ...✔✔ The spiral arms are places where
stars are formed from clouds of gas and dust
Where are you in the Universe? If you had to give
directions to your location in the Universe, what
directions would you give? - .....ANSWER ...✔✔ We
are the third planet away from the Sun. Our Solar
System is located in one of the spiral arms of the Milky
Way Galaxy, one within the Local Group of galaxies
Why do astronomers now label Pluto a "dwarf planet"?
- .....ANSWER ...✔✔ Due to its small size and the fact
that it is not alone in its orbit.
What is the difference between the Solar System, the
Galaxy, and the Universe? - .....ANSWER ...✔✔ The
Solar System is one planetary system (our Sun and
objects that orbit it). The Milky Way Galaxy contains
our Solar System and billions of other planetary systems.
The Universe includes everything.
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Why is it difficult to detect planets orbiting other stars? -
.....ANSWER ...✔✔ Extrasolar planets are small, much
fainter than the stars that they orbit, and very close to
their parent stars.
Why are light-years more convenient than miles,
kilometers, or AU for measuring the distances to stars
and galaxies? - .....ANSWER ...✔✔ Distances in other
units would require very large numbers. Additionally, the
distance in light-years tells us how far back in time we
are viewing the star or galaxy
How does the scientific method give scientists a way to
know about nature? - .....ANSWER ...✔✔ By testing
and refining ideas to describe better how nature works.
First, scientists try to form hypotheses that explain
observations
What does the size of the star image in a photograph
tell you? - .....ANSWER ...✔✔ How bright it appears
from Earth
metric system - .....ANSWER ...✔✔ simplifies
calculations
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scientific notation - .....ANSWER ...✔✔ for very large
or very small numbers.
The Solar System - .....ANSWER ...✔✔ includes the
Sun at the center, all of the major planets that orbit
around it—Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus, and Neptune—plus the moons of the planets
and other objects such as asteroids, comets, and dwarf
planets like Pluto, bound to the Sun by its gravity.
astronomical unit (AU) - .....ANSWER ...✔✔ is the
average distance from Earth to the Sun
Milky Way Galaxy - .....ANSWER ...✔✔ The Milky
Way Galaxy is about 80,000 ly in diameter and
contains more than 100 billion stars including our Sun.
Big Bang - .....ANSWER ...✔✔ Universe began about
14 billion years ago in an event called the Big Bang
that filled the Universe with hot gas.
scientific method - .....ANSWER ...✔✔ in which
scientists test hypotheses against evidence from
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experiments and observations. This method is a powerful
way to learn about nature.
Scientific theories - .....ANSWER ...✔✔ Must be
testable
Must be continually tested
Should be simple
Should be elegant
The "Obvious" View - .....ANSWER ...✔✔ Stars that
appear close in the sky may not actually
be close in space
one sidereal day has passed - .....ANSWER ...✔✔
stars aren't in quite the
same place 24 hours later,
though, due to Earth's
rotation around Sun; when
they are once again in the
same place
solar day - .....ANSWER ...✔✔ Daily cycle, noon to
noon, is diurnal motion
ASTR 102 Exam Questions with 100% Correct
Answers | Updated &Verified | | 100% Score
What are the Milky Way Galaxy's spiral arms? -
.....ANSWER ...✔✔ The spiral arms are places where
stars are formed from clouds of gas and dust
Where are you in the Universe? If you had to give
directions to your location in the Universe, what
directions would you give? - .....ANSWER ...✔✔ We
are the third planet away from the Sun. Our Solar
System is located in one of the spiral arms of the Milky
Way Galaxy, one within the Local Group of galaxies
Why do astronomers now label Pluto a "dwarf planet"?
- .....ANSWER ...✔✔ Due to its small size and the fact
that it is not alone in its orbit.
What is the difference between the Solar System, the
Galaxy, and the Universe? - .....ANSWER ...✔✔ The
Solar System is one planetary system (our Sun and
objects that orbit it). The Milky Way Galaxy contains
our Solar System and billions of other planetary systems.
The Universe includes everything.
,2|Page
Why is it difficult to detect planets orbiting other stars? -
.....ANSWER ...✔✔ Extrasolar planets are small, much
fainter than the stars that they orbit, and very close to
their parent stars.
Why are light-years more convenient than miles,
kilometers, or AU for measuring the distances to stars
and galaxies? - .....ANSWER ...✔✔ Distances in other
units would require very large numbers. Additionally, the
distance in light-years tells us how far back in time we
are viewing the star or galaxy
How does the scientific method give scientists a way to
know about nature? - .....ANSWER ...✔✔ By testing
and refining ideas to describe better how nature works.
First, scientists try to form hypotheses that explain
observations
What does the size of the star image in a photograph
tell you? - .....ANSWER ...✔✔ How bright it appears
from Earth
metric system - .....ANSWER ...✔✔ simplifies
calculations
,3|Page
scientific notation - .....ANSWER ...✔✔ for very large
or very small numbers.
The Solar System - .....ANSWER ...✔✔ includes the
Sun at the center, all of the major planets that orbit
around it—Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus, and Neptune—plus the moons of the planets
and other objects such as asteroids, comets, and dwarf
planets like Pluto, bound to the Sun by its gravity.
astronomical unit (AU) - .....ANSWER ...✔✔ is the
average distance from Earth to the Sun
Milky Way Galaxy - .....ANSWER ...✔✔ The Milky
Way Galaxy is about 80,000 ly in diameter and
contains more than 100 billion stars including our Sun.
Big Bang - .....ANSWER ...✔✔ Universe began about
14 billion years ago in an event called the Big Bang
that filled the Universe with hot gas.
scientific method - .....ANSWER ...✔✔ in which
scientists test hypotheses against evidence from
, 4|Page
experiments and observations. This method is a powerful
way to learn about nature.
Scientific theories - .....ANSWER ...✔✔ Must be
testable
Must be continually tested
Should be simple
Should be elegant
The "Obvious" View - .....ANSWER ...✔✔ Stars that
appear close in the sky may not actually
be close in space
one sidereal day has passed - .....ANSWER ...✔✔
stars aren't in quite the
same place 24 hours later,
though, due to Earth's
rotation around Sun; when
they are once again in the
same place
solar day - .....ANSWER ...✔✔ Daily cycle, noon to
noon, is diurnal motion
