Astronomy Unit 1: The Earth, Moon, and Sun Systems
What causes day and night to occur?
The rotation of the Earth on its axis
How many types of lunar eclipses are there?
There are 3 types of lunar eclipses: a penumbral eclipse, a partial eclipse, and a total eclipse. A penumbral eclipse occurs when the Moon passes only through Earth's shadow that is slightly blocking some of the sunlight, causing the full moon to look dimmer and slightly sun reddish in color. When a part of the Moon's surface passes through Earth's shadow, we see a partial eclipse. A total eclipse of the Moon occurs when the Moon travels completely into the Earth's shadow that is blocking sunlight.
What occurs in January when the Earth is closest to the Sun?
A perigee
What are solar and lunar eclipses?
A solar eclipse happens when the moon is positioned directly between the Earth and the Sun, and the Earth passes into the shadow of the Moon. A lunar eclipse occurs when the Earth is positioned directly between the Sun and the Moon, and the Earth casts a shadow on the Moon.
The summer season is closely linked to what?
A solstice because the Earth is very close to the Sun
Approximately how often does the Moon revolve around the Earth?
Every 30 days
True/False: The Sun appears to rise each morning in the west
False
What makes gravity a vital factor within our universe? How does it influence the universe?
Gravity is responsible for the shape of the Earth, and grounding life forms instead of allowing them to float around. Gravity keeps moons in orbit around their planets and keeps planets in orbit around the Sun. Without gravity, the Earth would not stay a proper distance from the Sun to get necessary light and heat.
If one were to horizontally divide the Earth in half at the equator, each half would be a ___________?
Hemisphere
Which one of the theories about the Moon's creation do you most agree with? Why?
I want to believe the Capture Theory because it makes more sense to me that the Earth would collect particles to create a Moon; especially since I am not aware of any leftover damage to the Earth as a result of a giant impact. However, science supports the Giant Impact Theory because the moon orbits the Earth in an elliptical path, and it is made of elements similar to the Earth's crust suggesting that it was actually part of the Earth at one time.
If you were an astronaut on the Moon, what would you experience? What would you see from your perspective?
If I were an astronaut on the Moon, I would weigh 1/6th of what I weigh on Earth. I would not be able to breathe without an oxygen mask because the Moon's gravity is not strong enough to maintain a thick atmosphere. I would see craters on the Moon. If I were on the near side of the Moon, I would see the Earth; if I were on the far side of the Moon, I would never see the Earth.
The Sun illuminates ______________ of the Moon at all times
One-half
Because of the Earth's _________, the Sun and other stars appear to be moving across the sky
Rotation
How do the Sun, Earth, and Moon depend on each other?
The Earth depends on the Sun to stay in orbit, to cause night and day, to change seasons, and to provide heat and light for the Earth's life forms. The Earth depends on the Moon for ocean tides.
How does the Earth move within the solar system?
The Earth orbits the Sun in an elongated, closed-curved path called an ellipse. The rate of revolution around the Sun is once every 365 days, 6 hours, and 9 minutes. The Sun isn't the exact center of the ellipse, but located closer to one end more than the other. This positioning causes distance between Earth and the Sun to change throughout the revolution. A perigee occurs (in January) when Earth is closest to the Sun. An apogee occurs (in July) when Earth is farthest from the Sun.
How are seasons created?
The Earth's tilt causes one hemisphere to be closer than the other hemisphere to the Sun. The hemisphere that is closer experiences summer, while the hemisphere that is further away experiences winter.
Why do seasonal and night-day cycles occur?
The Earth's tilt causes one hemisphere to be closer than the other hemisphere to the Sun. The hemisphere that is closer experiences summer, while the hemisphere that is further away experiences winter. The Earth rotates on its axis once every 23 hours and 56 minutes. During night, one's area of Earth rotated so it is facing away from the Sun.
Which ancient society first coined the word "astronomy" and contributed important early work in this discipline?
The Greeks
How are the Sun and Moon different? Compare and contrast these celestial bodies
The Moon is egg shaped, whereas the Sun is almost perfectly round. The Sun is stationary (not a satellite), whereas the Moon orbits the Earth on an elliptical path. Both the Sun and the Moon can be seen with the naked eye from Earth. The Earth gets its sense of time from both the Sun (seasons, days and nights) and the Moon (months, days and night). The Moon is smaller than the Earth; the Earth is smaller than the Sun.
Why does summer receive more daylight hours than winter?
The hemisphere of the Earth is tilted more toward the Sun
What are the characteristics of the Moon?
The Moon orbits Earth in an elliptical path. Its rotation and revolution speed are equal, causing only one side of the Moon to always face the Earth. The Moon is shaped like an egg, has large craters, and varying shades of grey colors visible to the naked eye. The different grey colors indicate plains on the Moon. Dark grey plains called Maria formed when basins on the Moon filled with lava after craters were formed. The Moon is about 27% the size of Earth and 1.7% the mass of Earth, causing gravity on the Moon to be about 1/6 of Earth's gravity.
How does the Moon manipulate the tides on Earth?
The Moon's and Sun's gravitational pulls on Earth are responsible for water levels rising/falling (it's a natural phenomenon. Tides occur because the Moon's gravity decreases with distance from the Moon. Gravity exerts greatest force on water closest to the Moon, causing 2 bulges of water to occur on opposite sides of Earth, as Earth rotates in relation to the Moon, these bulges of water move to follow the Moon. When the Moon, Earth, and Sun line up is space, high tides are higher and low tides are lower than usual, creating a spring tide. When the Sun, Earth, and Moon positioned to form a right triangle (are located 90-degrees in relation to one another) high tides are lower and low tides are higher than normal, creating a neap tide.
What is responsible for tides at the beach?
The Moon's gravitational pull, the Sun's gravitational pull, and the Earth's response to the Moon and Sun's gravitational pulls
How does the Moon contribute to Earth's tides?
The Moon's gravity causes the water on the Earth closest to the moon, and the opposite side from the Moon, to bulge creating a high tide. The level of water on the other areas of the Earth fall, creating a low tide.
How is the Moon dependent on the Sun?
The Moon's phases help us keep track of months. Its phase changes depend on how much sunlight is visible/blocked on its hemisphere that faces the Earth.
What would you say is the strongest force in our universe: the Sun, the Moon, or Earth? Support your answer with at least two facts
The Sun is the strongest force in our universe. The name "solar system" implies that the Sun has the most important role. The planets in our universe need the Sun for heat and light. The planets in our universe need the Sun's gravity to remain in orbit.
What are the phases of the Moon?
The appearance of the Moon is evolving (look like it is growing/shrinking) in a cyclic fashion because of its rotation as it revolves around the Earth in relation to the Sun. As the Moon orbits Earth, it moves from the west to east, changing position among the background of the Sun's light. It's position relative to the Sun changes, and as a result, we see different parts of the moon illuminated in different lunar phases. The Moon's current phase depends on how much of its sunlit hemisphere is facing the Earth. There are 8 lunar phases of the lunar cycle. The lunar cycle repeats its process every lunar month (which occurs about every 29.5 days). The lunar cycle begins with the new Moon phase (when the moon is closest to the Sun is space, and its dark hemisphere faces Earth). When Moon phases appear to get larger, they're called waxing phases. When Moon phases appear to decrease in size, they're called waning phases.
How many types of solar eclipses are there?
There are 3 types of solar eclipses: annular, partial, or total. An annular eclipse occurs when the Moon is farthest from Earth and not able to completely block out light from the Sun, and a thin ring of Sun appears around the Moon's outer edge. A partial (solar) eclipse occurs when the Moon is positioned between the Sun and Earth, and the Sun is only partially covered by the Moon (partial solar eclipses are more common than total solar eclipses). A total eclipses of the Sun will occur when the Moon is closest to the Earth, the Moon seems to be the same size as the Sun, and the Moon appears to completely cover the surface of the Sun. (Although the Sun is completely blocked, one can still see a circle of light around the Moon, which is the outer atmosphere of the Sun called the corona.)
True/False: During an equinox, the number of daylight hours and nighttime hours are nearly equal all over the world
True
True/False: The North Pole is in daytime for several weeks at a time, with no night time
True
True/False: The Sun and stars do not move
True
True/False: When the Sun, Earth, and Moon are positioned to form a right triangle, high tides are lower than normal
True
How are lunar and solar eclipses created?
When the Earth is between the Sun and the Moon, the Earth blocks the light so the Moon appears dark/black; this is a lunar eclipse. When the Moon is between the Sun and the Earth, the Moon blocks the light so the Sun appears dark/black; this is a solar eclipse.
