Astronomy Review #6
1. What type of eclipse occurs when the moon enters Earth’s shadow?
Lunar
2. What phase of the moon follows new moon?
Waxing Crescent
3. What are the four main theories of the formation of the moon?
Twin Theory, Capture Theory, Fission Theory (spin theory), Giant Impact
4. Which theory of the moons formation is the accepted theory?
Giant Impact
5. At any one time what percentage of the moon is lit up by the sun?
50%
6. What type of eclipse is more easily viewed by large numbers of people?
Lunar, with in theory with clear skies half the people on Earth can see it.
7. How many high and low tides occur in the oceans here on Earth each day?
2 High and 2 low
8. What are tides doing to the rotation of the Earth?
Slowing down the Earth’s rotation
9. Why is there a high tide on the Earth facing the moon?
The Moons gravity pulls the water away from the Earth.
10. Why is there a second high tide on the side of the Earth away from the moon?
1. The moon pulls the Earth away from the water.
2. Earth orbiting around the Earth/moon center of gravity. (swinging bucktet
of water)
11. When the amount of the moon that we see lit by the sun is decreasing, is the
Moon Waxing or Waning? Waning.
12. How does the location of the moon affect tides?
One high tide is towards the moon and the second is opposite the moon.
13. How does the location of the sun affect tides?
If the Sun and moon line up the sun adds to the tides. Otherwise the sun
decreases the tides.
14. Are tides higher along shorelines or in the open ocean?
Tides are very small in the open ocean. The water “piles” up at the
shorelines.
15. Why does the moon rise 50 minutes later each day?
Because the moon is orbiting the Earth.
16. How many times per year can eclipses occur?
There are two “Eclipse periods” per year
17. When is the Earth closest to the Sun?
January 4th or 5th
18. What is the difference between a partial, annular and total solar eclipse?
In a partial eclipse only part of the sun is covered by the moon. A total
eclipse the sun is completely hidden. In an annular eclipse the moon is
too far from the Earth so the moon can’t cover the whole sun causing a
ring of sun to show.
19. If the moon is at its closest point in its orbit to the Earth, how many days will it
be until it is at its farthest point? About 14 days (half an orbit)
20. How often on average do total solar eclipses occur at any spot on Earth?
About 370 years
21. How fast does Earth travel in its orbit around the Sun?
About 67000 miles/hour (more than 18 miles/second)
22. When will the next total solar eclipse be visible somewhere in the United States?
August 21th 2017
23. What phase must the moon be in for a solar eclipse to occur? A lunar eclipse?
New moon for a solar eclipse and full moon for a lunar.
24. How can you tell if the Moon is Waxing or Waning just by looking at it?
Waxing moons are lit on the right and waning moons are lit on the left.
25. Why is the Earth easier to land on then is the Moon or Mars?
The Earth’s atmosphere acts as a “brake” to slow down a spacecraft so no
fuel is needed to land.
26. Why is launching a rocket off the surface of the Earth so difficult?
The gravity and atmosphere
27. In what two major ways is the interior of the moon different than the interior of
the Earth? The interior of the moon has cooled and solidified and it has no iron
core.
28. On March 5th Earth and Mars will be only .67 au’s apart. Approximately how far
apart will they be one year later if it takes Mars two years to circle the Sun?
About 2.67 au’s. One au from Earth to Sun, then one more au to Earth’s
orbit plus .67 au’s out to Mars.
29. Why must any mission to Mars last at least two years?
Astronauts need to wait for Earth to catch back up to Mars.
30. If the moon is full today, about how many days until new moon?
Just over 14 days.
31. Why is it more difficult to land on Mars than on the moon?
More gravity and a thin atmosphere that complicates a powered landing.
32. Why don’t eclipses happen every month?
The Moons orbit is tilted so that it passes above or below the sun most
months. Only when the moon is crossing the Earth/Sun plane at full
moon or new moon can an eclipse occur.
33. If the Mars-Sun distance varies between 1.38 and 1.67 au’s over the course of
each orbit. What percent farther from the Sun is Mars at 1.67 au’s than it is at
1.38 au’s? (1.67-1.38)/1.38 X 100 = 21%
34. Why do high tides occur 50 minutes later each day?
Because the moon rises 50 minutes later each day because it is moving
around the Earth.
35. Why are high tides lower when the moon is not lined up with the Sun?
Because the sun is not “helping the moon” make the tides higher.
36. Why don’t we ever see the back side of the moon?
Because the moon rotates on its axis at the same rate that it orbits the
Earth.
37. Why does Mr. Stimpson think that it would have been impossible for NASA to fake
the moon landing?
It would have been impossible to fool the Soviets (Russians).
38. What is a gibbous moon?
A gibbous moon is one that is between full and either first quarter or last
quarter. In other words over half of what we see is lit up.