Rotation & Day/Night
What direction does Earth rotate when viewed from above the North Pole
counterclockwise
From which direction do the sun, moon, and stars appear to rise?
East
How long does it take the moon to go through its full set of phases (one lunar cycle)?
About one month (about 29.5 days)
What type of eclipse happens when the moon is directly between the sun and Earth?
Solar eclipse
When viewed from above the North Pole, does Earth rotate clockwise or counterclockwise?
Counterclockwise
About how long it takes Earth to complete one full rotation
24 Hrs
From which direction do the sun, moon, and stars appear to set?
West
What causes the phases of the moon that we see from Earth?
The moon's phases are caused by the moon changing position relative to Earth and the sun as it orbits Earth, which changes the fraction of the sunlit half visible from Earth.
What type of eclipse happens when Earth is directly between the sun and the moon?
Lunar eclipse
True or False: The moon produces its own light
False (the moon reflects sunlight)
What daily cycle is caused directly by Earth's rotation?
The cycle of daytime and nighttime
Why do the sun, moon, and stars appear to move across the sky even though they are not orbiting Earth daily?
Because Earth is rotating on its axis; the rotation makes celestial objects appear to move even though their positions relative to distant stars change much more slowly.
Name the phase of the moon when we see exactly half of the lit side.
First quarter or last quarter (half moon)
Why can't we have a solar eclipse every new moon?
Because the moon's orbit is tilted about 5° relative to Earth's orbit around the sun, the moon usually passes above or below the direct line between Earth and sun; only when the moon is near a node does it line up for an eclipse.
What term describes the path the moon takes around Earth?
Orbit
If Earth rotated from east to west instead, how would the apparent motion of the sun across the sky change?
The sun would appear to rise in the west and set in the east (reverse east–west motion).
If you watch the sky from the Southern Hemisphere, does the apparent path of the sun look the same or different than from the Northern Hemisphere? Briefly explain.
The apparent path is different — in the Southern Hemisphere the sun's path is tilted differently across the sky and objects may appear to move in the opposite direction around the zenith compared to the Northern Hemisphere.
Explain why the sun always lights half of the moon, but we do not always see that half.
The sun always illuminates half the moon; we see varying portions of that illuminated half depending on the moon's position in its orbit relative to Earth and the sun.
During a total lunar eclipse, what happens to the moon's appearance and why does it look that way?
The moon darkens and often appears reddish because it is in Earth's shadow and sunlight refracted through Earth's atmosphere reaches the moon (scattering shorter wavelengths and letting red light pass).
How does the tilt of Earth's axis affect day length during a single rotation (24 hours)? (Short answer)
Earth's tilt does not significantly change day length during a single rotation; day length differences occur across the year as Earth orbits the sun because the tilt causes varying sunlight angles and daylight duration.
Explain why different places on Earth experience day and night at different times (use rotation in your answer).
Because Earth rotates on its axis, different longitudes face the sun at different times; as Earth turns, regions move into and out of sunlight, producing day and night.
Describe how Earth's rotation causes the apparent east-to-west motion of celestial objects, using the terms "observer," "Earth's rotation," and "apparent motion."
Earth's rotation carries an observer eastward; because the observer is turning toward the east, celestial objects appear to move westward across the sky — this apparent motion is due to the observer's motion, not rapid movement of the objects.
Describe the sequence of major moon phases in order starting with new moon and ending with new moon, and explain why that sequence repeats.
New moon → waxing crescent → first quarter → waxing gibbous → full moon → waning gibbous → last quarter → waning crescent → new moon. The sequence repeats because the moon continuously orbits Earth and returns to the same positions relative to Earth and sun.
Compare and contrast the conditions (positions of sun, Earth, and moon) required for a solar eclipse and a lunar eclipse, and explain which type can be seen by more people on Earth and why.
Solar eclipse: Sun — Moon — Earth (moon between sun and Earth); only people within the moon's shadow on Earth can see it (small area). Lunar eclipse: Sun — Earth — Moon (Earth between sun and moon); the entire night side of Earth can see it, so many more people can observe a lunar eclipse.
What is responsible for Earth Season,"s
Earth Tilt