Eclipses & Planetary Motion Flashcards
1
Q
What causes eclipses?
A
When either passes through the other’s shadow, we have an eclipse.
2
Q
Penumbra
A
The earth’s shadow
3
Q
Umbra
A
The darkest part of the earth’s shadow
4
Q
Lunar eclipse
A
Moon, Earth, Sun
5
Q
What phase must the moon be in for a lunar eclipse?
A
Full moon
6
Q
Solar eclipse
A
Earth, Moon, Sun
7
Q
What phase must the moon be in for a solar eclipse?
A
New moon
8
Q
Prograde motion
A
The apparent West to East motion of objects (over many nights) as compared to the stationary background stars.
9
Q
Retrograde motion
A
The apparent East to West motion of objects (over many nights) as compared to the stationary background stars.
