Chapter 2 - Part 2 Flashcards
How many days does it take the moon to orbit around the Earth?
27.3 days
How does the moon shine if it doesn’t have its own light source?
It reflects light from the sun
The different appearances of the moon as it orbits the Earth
Phases
Occurs when the moon is between the Earth and the Sun, the entire far side of the moon is illuminated
New moon
List the phases of the moon starting from a new moon
- New moon
- Waxing crescent
- First quarter
- Waxing gibbous
- Full moon
- Waning gibbous
- Third quarter
- Waning crescent
Occurs a few days after a new moon where only a sliver of the right side of the moon is illuminated
Waxing crescent
Why is our view of the moon constantly changing?
The moon is orbiting the earth, so the amount of sunlight that reflects off of it depends on its location
When does a new moon rise?
Sunrise
When does a full moon rise?
Sunset
Occurs when the moon has moved a quarter away around the earth and half of it is illuminated
First quarter
Occurs after the first quarter where more than half of the right side of the moon is illuminated
Waxing gibbous
Occurs when the Earth is between the Sun and moon, the entire near side of the moon is illuminated
New moon
Occurs when the moon is starting to get smaller, where more than half of the left side of the moon is illuminated
Waning gibbous
Occurs when the left half the moon is illuminated and the right side isn’t
Third quarter
Occurs when only a sliver of the left side of the moon is illuminated
Waning crescent
What is a solar month?
The time between one new moon and the next
What is a sidereal month?
The time it takes the moon to complete one orbit around the Earth
What is a solar month measured with respect to?
The stars
What is a sidereal month measured with respect to?
The sun
How long is a solar month?
29.53 days
How long is a sidereal month?
27.32 days
Why do we only see one side of the moon?
The time it takes the moon to make one revolution around the Earth is the same amount of time it takes the moon to make one rotation
Describe the synchronous rotation of the moon
The amount of time for the moon’s rotation and the earth’s rotation is the same
What is a lunar day
The time between one sunrise and the next as seen from the moon (24 hrs & 50 min)
What is it called when the earth, moon, and sun line up?
An eclipse
The total or partial obscuration of one celestial body by another celestial body
Eclipse
Occurs when the moon passes between the sun and earth?
Solar eclipse
The darker inner part of the earth’s shadow
Umbra
An eclipse where the sun’s light is completely blocked by the moon
Total solar eclipse
The lighter part of the earth’s shadow
Penumbra
An eclipse where the sun’s light is partially blocked by the moon
Partial solar eclipse
An eclipse where the sun’s outer ring isn’t blocked by the moon
Annular solar eclipse
Why is the solar eclipses viewing area shorter than the lunar eclipses viewing area?
The diameter of the earth’s shadow is a lot larger than the diameter of the moon’s shadow
Occurs when the moon moves through the earth’s shadow
Lunar eclipse
Occurs when the moon is entirely within the earth’s shadow
Total lunar eclipse
During a total lunar eclipse, why does the moon appear to be red?
The red light from the sun is bent by the earth’s atmosphere and it hits the moon
Occurs when the moon passes through the penumbra part of the earth’s shadow
Penumbral lunar eclipse
Occurs when the earth’s shadow partially blocks the moon?
Partial lunar eclipse
Why do we not have eclipses every month?
The moon’s orbit and the earth’s orbit aren’t on the exact same plane
The line where the sun’s and moon’s orbital planes intersect
The line of nodes
The times where the line of nodes points in the direction of the sun
The ecliptic seasons
What conditions need to be met in order for an eclipse to happen?
The sun, moon, and earth need to be aligned on the line of nodes
When the moon is closest
Perigee
When the moon is farthest
Apogee
The earth rotates on it’s axis and revolves around the sun
(Remember this)
The plane of earth’s orbit
The ecliptic plane
