Question | Answer |
which statement best describes how variation in the Earth-Sun distance affects the seasons? | The variation in Earth–Sun distance over the course of each year has virtually no effect on the seasons. |
You’ve now seen that Earth’s varying distance cannot be the cause of our seasons. So what is the cause of the seasons? | The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year. |
At most times, Mars appears to move __________ relative to the stars. The exceptions are during its periods of apparent retrograde motion, when Mars appears to move __________ relative to the stars. | to the left (eastward), to the right (westward) |
If you wanted to document the apparent retrograde motion of Mars, you would need to measure and record Mars's __________ over a period of __________. | position among the constellations, several months |
What is really happening in space during the periods when we see Mars going through apparent retrograde motion? | Earth is passing by Mars in its orbit around the Sun. |
Consider a time when Mars is in the middle of one of its periods of apparent retrograde motion. During this time, Mars appears _____ in our night sky and crosses the meridian around _____. | brightest , midnight |
Should these facts alone have been enough to convince the ancient Greeks that Earth really does go around the Sun? | No, because the Greeks had an Earth-centered model that also accounted for apparent retrograde motion. |
Two stars that are in the same constellation: | may actually be very far away from each other. |
The North Celestial Pole is 35.0∘ above your northern horizon. This tells you that: | you are at latitude 35.0∘ N. |
Beijing and Philadelphia have about the same latitude but very different longitudes. Therefore, tonight's night sky in these two places: | will look about the same. |
n winter, Earth's axis points toward the star Polaris. In spring: | the axis also points toward Polaris. |
When it is summer in Australia, the season in the United States is | winter. |
If the Sun rises precisely due east: | it must be the day of either the spring or fall equinox. |
A week after full moon, the Moon's phase is: | third quarter. |
Some type of lunar or solar eclipse (not necessarily a total eclipse) occurs | at least four times a year |
If there is going to be a total lunar eclipse tonight, then you know that: | the Moon's phase is full. |
When we see Saturn going through a period of apparent retrograde motion, it means | Earth is passing Saturn in its orbit, with both planets on the same side of the Sun. |