U1 Earth-Sun-Moon System Flashcards
Evidence of Earth's Rotation and Revolution, Insolation and Seasons, Apparent Pathway of the Sun, Moon Phases and Tides
Foucault’s Pendulum
a large pendulum that knocks down sticks every hour due to the Earth’s rotation
What is the primary cause of seasonal changes on Earth?
tilt of the Earth’s axis
How much is Earth’s axis tilted?
23.5 degrees
What causes the clockwise direction of flow of the ocean currents in the Northern Hemisphere?
Coriolis effect
What is the name of the star in the Northern Hemisphere that appears to stay in the same location as the Earth rotates at night?
Polaris
solar time
calculation of elapsed time (how much time has passed) using the apparent movement of the Sun
constellation
a group of stars’ location and arrangement relative to other stars
Which motion causes observers on Earth to see different constellations at different times of the year?
Earth revolves around the Sun
Which motion causes the stars to appear to move across the night sky?
Earth’s rotation
spring tide
2 times during the year when we experience the greatest variance (change) between high and low tides; this occurs due to the Sun, Earth, and Moon being in alignment (you will see either a full or a new moon)
neap tide
2 times during the year when we experience the least variance (change) between high and low tides; this occurs due to the Sun, Earth, and Moon being forming a 90 degree angle (you will see only half the moon)
What season will the Northern Hemisphere be experiencing when the North Pole is tilted towards the Sun?
summer
insolation
the amount of solar radiation that reaches the Earth’s surface
angle of incidence
the angle at which the Sun’s ray hits the Earth’s surface AS MEASURED FROM A LINE PERPENDICULAR TO THE SURFACE
How many hours of sunlight does the equator get throughout the year?
12 hours; since the equator does change much throughout Earth’s revolution even though the Earth is tilted
What is the relationship between latitude and duration of insolation in the Northern Hemisphere during the summer?
As the latitude increase, the duration of insolation (hours of sunlight) increases.
When it is 11am in Boston, what time is it in San Diego?
8am
What causes a lunar eclipse?
the moon’s orbital plane places the moon in a position where the Earth’s shadow falls on the moon (moon is blocked from the Sun)
What causes a solar eclipse?
the moon’s orbital plane places the moon in a position where the moon’s shadow falls on the Earth (Sun is blocked from the Earth)
What affects something’s ability to absorb insolation?
- color (black absorbs more and white less)
- texture (rough absorbs more insolation while smooth reflects it)
How much time passes from a high tide to the next high tide?
about 12 hours
How much time passes from a high tide to a low tide?
about 6 hours
During which season in the Northern Hemisphere is the Earth at its aphelion?
summer
How many degrees does the Earth rotate in 1 hour?
15 degrees (360 degrees/24 hours)
What time of the day is your shadow the shortest?
when the Sun is directly over head because the sun is at a higher angle
What time of the year is your shadow the shortest?
summer because the sun is higher in the sky
The angle in which you see Polaris in the Northern Hemisphere is the same as your ________________.
latitude; ex: in NYC we see Polaris at about 41 degrees in the sky from the horizon because our latitude is about 41 degrees N
During the spring and fall equinox, how many hours of daylight will there be?
12 hours; equinox means equal number of day/night hours (happens in March and September)
Tides are both ___________ and ____________.
cyclic and predictable
