Sunrise/Sunset/Gravity
1. When you watch the sunset, is the Sun really moving down? What's happening?
No, the Sun is not actually moving when you watch the sunset. What is really happening is that the place you are standing on the Earth is spinning in a direction away from the Sun.
1. In ancient times, why would a cloudy day make it hard to know what time it was?
Ancient people used shadow clocks to tell time. Without the sun, you can't use a shadow clock!
2. During what season is the Sun highest in the sky?
The Sun is highest in the sky during summer.
On a flight across the ocean your plane crash-lands on a remote island with no one around to help. Everyone survives but has amnesia (memory loss), so no one can remember the date. Everyone's belongings were destroyed when the plane crashed.
1. How could you figure out roughly what month it is?
You could tell roughly which month it is by seeing which constellations are at their highest point in the evening after sunset. For example, if you see Orion at its highest point in the sky in the evening, then you know the month is December, January, or February.
1. What did the word planet originally mean?
It meant wandering star.
2. Can the Sun ever appear to move down in the morning? Explain.
No, in the morning the Sun will always appear to move upwards. It only appears to move downwards after it has reached its high point, which is noon. After noon (midday) the Sun appears to start moving down in the sky.
2. Say one morning the Earth suddenly stopped spinning. Would a shadow clock still work?
A shadow clock only works because the shadow moves across the dial. So if the Earth stopped spinning, the shadow clock would be useless!
3. If it's 8 o'clock in the evening and the Sun is still out, what season is it? How do you know?
It’s summer. I know because in summer the daytime is longer and the Sun sets later.
2. Cruise ships might be sailing during the vacation months of June, July, and August. Which constellation(s) should you look for, so you know when to light fires to send signals to the ships?
You should look for a summer constellation like Scorpius
2. What invention changed how we think about planets? What did it do?
The telescope changed how we think about planets. It made the planets look bigger, so we noticed they were worlds, not just dots of light.
3. From Sunday evening to Friday evening, how many times around does the Earth spin?
The Earth spins five complete rotations from Monday to Friday.
3. The planet Mercury takes 176 days to do one spin around its pole. Compared to the Earth, would the Sun appear to move more quickly across Mercury's sky or more slowly? Why?
The Sun would appear to move much more slowly across Mercury's sky than Earth's sky, because Mercury spins much more slowly than the Earth.
4. If it's 7:30 in the morning and the Sun isn't up yet, what season is it? How do you know?
It’s winter. I know because in winter the daytime is shorter and the Sun rises later.
1. Where does the concept of a month come from?
It comes from the word 'moon' which used to be pronounced "moonth." A month is the 28 days it takes for the Moon to do one orbit around the Earth. During that orbit, the Moon goes from New Moon to Full Moon, and then back to New Moon again.
3. Which planet moves more slowly across the sky: Saturn or Mars? How do you know?
Saturn moves more slowly across the sky than Mars. I know because the farther a planet is from the Sun, the more slowly it moves in its orbit. Saturn is farther from the Sun than Mars.
2. Which of the following statements about gravity and magnetism is NOT true?
d. Gravity pulls only on magnetic objects, but magnetism pulls on everything.
4. A girl named Lindsey has 4 creases on each finger instead of 3. If she counts like an Egyptian, what number will she count to with one hand?
16
Fall is usually a little warmer than spring. And yet, the Sun's path is the same in both seasons. Why do you think fall might be warmer than spring?
During cold winter weather, the water and the ground cool down. In spring, the sunlight has to warm up the water and ground before the days can get really warm, and that takes time. Fall follows summer, when the sunlight warms the water and ground. Before the days get cool, the water and ground must cool off, and that takes time.
2. Can you ever see the Moon during the day?
Yes, it is possible to see the Moon during the day. It's a little harder to notice because the Sun is so bright!
4. How can you tell the difference between a star and a planet in the sky?
Here are two ways to tell a planet apart from a star: 1. Planets don't stay put in one constellation. (They 'wander'.) 2. Through a telescope, you can actually see that a planet is a world. A star just appears as a dot of light.
3. Challenge: During what phase can the Moon only be seen at night--and not in the daytime at all? Bonus: How do you know?
The Full Moon is never seen in daytime. It rises when the Sun sets and can only be seen at night. I know because a Full Moon happens when the Moon is opposite from the Sun in the sky. That means a Full Moon cannot be out when the Sun is out.
1. When an apple falls to the ground, what is happening?
b. Gravity pulls the apple down, towards the the Earth.