We’re going on a pretend spaceship ride to the Moon just like Apollo astronauts did. But before we go to the Moon, let’s learn a little bit about the Moon. One of the great things about a planetarium is that we can make our pretend sky look like it is any time of the day or night. Right now, let’s imagine that it’s just before sunset.Point out sun. If you look very carefully around the planetarium sky, you might be able to see the planetarium Moon.
Do any of you see the planetarium Moon?
[Let someone point out the Moon.]
Now, a lot of people believe that the Moon and the Sun are never in the sky at the same time, but we see here that they can be.
We’re going to use our planetarium as a time machine now and speed a few hours into the future and let the Sun set.
DIGITAL EFFECT: Go To Night
Run diurnal motion and let the sun set. Go to approximately 90 minutes past sunset. This may need to be adjusted for your particular theater’s location. Have the Moon be low on the western horizon. Now the Moon is a lot easier to see.
People all over the world and all throughout time have looked at the Moon and come up with different descriptions for the shape of the Moon.
Raise your hand if you have a word or a way to describe the shape of the Moon as it appears in the sky now?
[A smile, a banana, etc. Accept any answers.]
Astronomers – people who study the stars and other objects in the sky – call the Moon a “crescent Moon” when it looks like this.
Can you say “Crescent Moon”?
Now we’re going to let the sky go dark for a minute and then our planetarium as a time machine to skip ahead a few days into the future now. We’re going to skip ahead about four days into the future. Are you ready?
Help me count four days….
As you count 1, 2, 3, 4:
DIGITAL EFFECT: 4 Days to Quarter
Run diurnal motion forward 4 days in 4 seconds to get to a waxing quarter moon phase. During this time, the Moon and stars are off, and the atmosphere and Sun are on. This gives the effect of seeing the Sun race across the sky and making the daylight flash to give the illusion of time passing by quickly.
Look around for the Moon and point to it when you see it. We’re still looking for the Moon right after sunset.
Turn Sun/Moon on.
What sort of shape does it have now?
[Half Moon, bowl, etc.] [Accept any answers.]
Astronomers call this kind of a Moon a “Quarter Moon”.
Can you say “Quarter Moon”?
Notice also that the Moon has now moved over in the sky from where it was four nights ago.
We’re going to prepare to jump a few more days into the future. Help me count!
DIGITAL EFFECT: 3 Days to Gibbous
Run diurnal motion forward 3 days in 3 seconds to get to a waxing gibbous moon phase. As with the jump before, the Sun races across the sky and the daylight flashes during the time travel.Point to the Moon if you can see it now.
What sort of shape does it have now?
[Egg shape, partly eaten cookie, etc. Accept any answers.]
Astronomers have a funny name for this funny-shaped Moon. They call this a “gibbous Moon.”
Can you say “gibbous”?
All gibbous means is that it looks like more than half of a filled circle, but less than a completely filled circle.
I’m going to fade the sky so we can jump a few more days into the future. Are you ready?
DIGITAL EFFECT: 4 Days to Full Moon
Run diurnal motion forward 4 days in 4 seconds to get to a full moon phase. As with the jump before, the Sun races across the sky and the daylight flashes during the time travel.
Point to the Moon if you can see it.
How would you describe this kind of Moon now? [Full.]
That’s right, this is a “Full Moon”.
Remember that the sun set over here.
[Point to the west.]
And now we have a Full Moon rising over on this side.
[Point to the Full Moon.]
If it’s a full Moon, it will always appear shortly after you see the sun set.
Now, if we were to continue looking for the Moon right after sunset tomorrow, we wouldn’t see it because it would be below the horizon. So, we’re going to speed up time a few hours again, and let the Moon rise.
Turn on soft music.
DIGITAL EFFECT: See Waning
Run diurnal motion until just before sunrise. At this point the Moon is about to set, in preparation for watching the waning phases.
A whole night has gone by!
What time of day should it be?
Let’s use our time machine and see how the Moon will change in the days after it’s a Full Moon.
Raise your hand if you know what might happen to the Moon as we go into the future.
Will it get bigger or smaller?
Let’s watch the Moon now, when we don’t have clouds to block our view.
DIGITAL EFFECT: 4 Days to Gibbous
Run annual motion 4 days in 4 seconds with the stars stationary to see a waning gibbous moon. For the waning phases, allow the audience to observe the Moon shrinking and moving in the sky. In contrast, during the waxing phases the point is for the audience to make predictions.
DIGITAL EFFECT: 3 Days to Quarter
Run annual motion 3 days in 3 seconds with the stars stationary to see a waning quarter moon.
DIGITAL EFFECT: 3 Days to Crescent
Run annual motion 3 days in 4 seconds with the stars stationary to see a waning crescent moon.
Finally, we see that the Moon actually disappears from view for a few days, and we call that a “New Moon” – because it’s the beginning of a new Moon cycle.
DIGITAL EFFECT: 4 Days to New Moon
To show how the Moon actually disappears, run annual motion 4 days in 4 seconds with the stars stationary to see a new moon, and keep the Moon in new phase.
DIGITAL EFFECT: Sunrise
Let the sun rise.