Opener 3/26

1. What does it mean to make a "To Scale Model"

It means all the distances and sizes of the objects are based on a scale. In the case of the video the scale is that the Earth's diameter is equal to the diameter of the small blue marble. All the other distances and sizes of objects are based on this ratio. They are all to proportion.

2. How does it feel for the Earth to be the size of a tiny blue marble?

Well this is up to everyone to decide, for me it's kinda cool knowing were just one tiny little piece of rock in this huge cosmos. For other's it might be scary feeling so small and insignificant. Maybe it gives us some perspective on our current problems on Earth?

3. What is inaccurate about the planetary motion in the video (think about modeling orbits)?

In the video the planetary motion is circular. The orbits are all the shape of circles. In actuality the shapes are ellipses (ovals) just as we saw in the Modeling Orbits lab. There are times when each planet is closer to the Sun and times when it is further away.

Opener 3/19

What factors affect the force of gravity?

As we've spoken about in class before and you learned about in yesterday's activity, Gravity is affected by mass and distance. The greater the mass of the two objects, the larger the force of gravity between them. However, the larger the distance is between the two objects the lower the force of gravity will be.

Opener 3/18

1. If gravity is pulling the Moon and Earth together, why don't they crash into each other?

Due to the force of gravity the Earth is pulling the Moon towards it, however the moon also has a velocity (speed with direction away from the Earth) and therefore INERTIA! So, although it's being pulled towards the Earth, it's also moving away. Those two factors, gravity & inertia, cause the moon to maintain it's orbit around the Earth.

Opener 3/17

What is the summer and winter solstice?

Summer solstice is the longest day of the year and winter solstice is the shortest day of the year. The Tropic of Cancer and Capricorn are the latitudes that receive 90 degree direct sunlight on their hemisphere's respective summer solstices.

When it is summer solstice in the Southern Hemisphere, which direction is the Northern Hemisphere pointed?

When it is summer solstice in the Southern Hemisphere, the Northern Hemisphere is pointed away from the Sun.

Opener 3/16

What is an equinox and why is it a significant day?

An Equinox is the moment when the Earth is neither tilted towards or away from the Sun and therefore all locations on earth receive 12 hours of daylight. On this day the Equator is the latitude that gets 90 degree direct sunlight.