Motion in Space
The imaginary line Earth rotates around.
What is its axis?
The direction the sun appears to move across the sky.
What is east to west?
The phase when the moon is completely dark.
What is new moon?
The type of eclipse where the moon blocks the sun.
What is a solar eclipse?
The best moon phase to land astronauts for maximum sunlight.
What is waxing or waning crescent?
The direction Earth rotates (viewed from the North Pole).
What is counterclockwise?
The time it takes Earth to complete one rotation.
What is 24 hours?
The meaning of "waxing" in "waxing crescent."
What is growing larger?
The darkest part of a shadow (hint: "umbra" or "penumbra").
What is the umbra?
The primary reason astronauts need sunlight on the moon.
What is visibility for exploration?
The term for Earth’s yearly path around the sun.
What is its orbit?
The reason we see different constellations in summer vs. winter.
What is Earth’s revolution around the sun?
The phase when the right half of the moon is lit (Northern Hemisphere).
What is first quarter?
The reddish color of the moon during a total lunar eclipse.
What is caused by Earth’s atmosphere bending sunlight?
The critical alignment for radio communication with Earth.
What is direct line of sight to Earth?
The experiment that proved Earth’s rotation using a swinging pendulum.
What is Foucault’s pendulum?
The star that remains fixed in the northern sky (hint: guides navigators).
What is Polaris (North Star)?
The number of days in a full moon cycle (synodic month).
What is 29.5 days?
Why solar eclipses don’t happen every new moon.
What is the moon’s orbit is tilted 5°?
The year humans first landed on the moon.
What is 1969?
The reason the moon rises ~50 minutes later each day.
What is its orbit + Earth’s rotation?
The scientific term for the sun’s daily path being highest at noon.
What is solar zenith?
The reason we always see the same side of the moon.
What is synchronous rotation?
The type of solar eclipse where the sun appears as a "ring of fire."
What is an annular eclipse?
The term for the moon’s gravity affecting Earth’s tides.
What are lunar tides?