GROSSMONT ASTRONOMY 110 FINAL
EXAM STUDY
GUIDE 2024 ACTUAL QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTION
What are constellations? How many are there? Ans✔- A group of
stars.88
What is the celestial sphere? Ans✔- An imaginary sphere that maps
all celestial objects.
What is the celestial equator? Ans✔- Earth's equator expanded
onto the celestial sphere.
What is an ecliptic? Ans✔- A circle on the celestial sphere
representing the sun's apparent path during the year.
What are the North and South celestial poles? Ans✔- Earth's north
and south pole expanded onto the celestial sphere.
What is the difference between the solar and sidereal day (in
minutes)? Ans✔- It rises 4 minutes earlier each successive
night, and the length of daylight hours varies. How long does it
take the Earth to rotate (in hours)? Ans✔- 24.
How long does it take the Earth to revolve (in decimal days)? Ans✔-
365.25
GROSSMONT
,How long does it take the Earth to precess (in years)? Ans✔-
26,000
What causes seasons? Ans✔- Earth's rotation axis inclined by 23.5
degrees.
When are the Spring and Fall equinox? Ans✔- Spring equinox is on
March 20th and Fall equinox is on September 22nd.
When is the Summer solstice? Ans✔- Summer solstice has the most
time of daylight and is on June 21st.
When is the Winter solstice? Ans✔- Winter Solstice has the least
time of daylight and is on December 21st.
How long is a lunar month? Ans✔- 29-30 days
How long is the Moon's orbit and rotation period? Ans✔- 27 days.
Why do we see phases of the Moon? Ans✔- The revolution of the
moon around the Earth allows us to see different amounts of the
Moon being illuminated.
Why do we see the same face of the Moon? Ans✔- The rotational
period is exactly the same as the orbital period.
What is a solar eclipse and how does it occur? Ans✔- A solar eclipse
occurs when the moon gets between Earth and the Sun, and only
occurs at the phase of new moon.
The three types of solar eclipses are partial, annular, and total.
GROSSMONT
, What is a lunar eclipse and how does it occur? Ans✔- A lunar
eclipse occurs when the moon passes directly behind the Earth, and
can only occur on a full moon night.
The three types of lunar eclipses are partial, penumbral, and total.
What was Aristotle's idea for the universe? Why was he wrong?
Ans✔ - He thought the Earth was the center of the universe, but it's
actually the Sun.
What was Ptolemy's idea for the geocentric model? Ans✔-
Epicycles, circles upon circles.
How did Ptolemy try to explain retrograde motion? Ans✔- With
epicycles, he could explain the complicated motion.
Why was Ptolemy wrong? Ans✔- They move in ellipses, and the Sun
is the center.
What was Eratosthenes' contribution to astronomy? Ans✔- He
measured Earths radius about 2300 years ago.
What were Aristarchus' contributions to astronomy? Ans✔- First
astronomer to have idea of heliocentric universe, and found
distances to the Sun and the Moon.
What was Copernicus' idea for the Universe? Ans✔- Planets moved
around the Sun in perfect circles.
How did Copernicus explain retrograde motion? Why was part of the
Copernican idea wrong? Ans✔- He used a lot of epicycles to make
GROSSMONT
EXAM STUDY
GUIDE 2024 ACTUAL QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTION
What are constellations? How many are there? Ans✔- A group of
stars.88
What is the celestial sphere? Ans✔- An imaginary sphere that maps
all celestial objects.
What is the celestial equator? Ans✔- Earth's equator expanded
onto the celestial sphere.
What is an ecliptic? Ans✔- A circle on the celestial sphere
representing the sun's apparent path during the year.
What are the North and South celestial poles? Ans✔- Earth's north
and south pole expanded onto the celestial sphere.
What is the difference between the solar and sidereal day (in
minutes)? Ans✔- It rises 4 minutes earlier each successive
night, and the length of daylight hours varies. How long does it
take the Earth to rotate (in hours)? Ans✔- 24.
How long does it take the Earth to revolve (in decimal days)? Ans✔-
365.25
GROSSMONT
,How long does it take the Earth to precess (in years)? Ans✔-
26,000
What causes seasons? Ans✔- Earth's rotation axis inclined by 23.5
degrees.
When are the Spring and Fall equinox? Ans✔- Spring equinox is on
March 20th and Fall equinox is on September 22nd.
When is the Summer solstice? Ans✔- Summer solstice has the most
time of daylight and is on June 21st.
When is the Winter solstice? Ans✔- Winter Solstice has the least
time of daylight and is on December 21st.
How long is a lunar month? Ans✔- 29-30 days
How long is the Moon's orbit and rotation period? Ans✔- 27 days.
Why do we see phases of the Moon? Ans✔- The revolution of the
moon around the Earth allows us to see different amounts of the
Moon being illuminated.
Why do we see the same face of the Moon? Ans✔- The rotational
period is exactly the same as the orbital period.
What is a solar eclipse and how does it occur? Ans✔- A solar eclipse
occurs when the moon gets between Earth and the Sun, and only
occurs at the phase of new moon.
The three types of solar eclipses are partial, annular, and total.
GROSSMONT
, What is a lunar eclipse and how does it occur? Ans✔- A lunar
eclipse occurs when the moon passes directly behind the Earth, and
can only occur on a full moon night.
The three types of lunar eclipses are partial, penumbral, and total.
What was Aristotle's idea for the universe? Why was he wrong?
Ans✔ - He thought the Earth was the center of the universe, but it's
actually the Sun.
What was Ptolemy's idea for the geocentric model? Ans✔-
Epicycles, circles upon circles.
How did Ptolemy try to explain retrograde motion? Ans✔- With
epicycles, he could explain the complicated motion.
Why was Ptolemy wrong? Ans✔- They move in ellipses, and the Sun
is the center.
What was Eratosthenes' contribution to astronomy? Ans✔- He
measured Earths radius about 2300 years ago.
What were Aristarchus' contributions to astronomy? Ans✔- First
astronomer to have idea of heliocentric universe, and found
distances to the Sun and the Moon.
What was Copernicus' idea for the Universe? Ans✔- Planets moved
around the Sun in perfect circles.
How did Copernicus explain retrograde motion? Why was part of the
Copernican idea wrong? Ans✔- He used a lot of epicycles to make
GROSSMONT
