Midterm Astronomy Flashcards
What is a solar eclipse?
Moon blocks the Sun (New Moon).
What is a lunar eclipse?
Earth blocks sunlight from the Moon (Full Moon).
What causes tides?
Caused by differences in how much gravity from the moon and the sun pulls different parts of earth
What are tidal bulges?
At any time there are 2 places with high tides and 2 places with low tides.
The close side is due to gravitational force from the moon (high tide)
The opposite side is due to inertia
What are spring tides?
(strongest) occur at New & Full Moons.
The gravity of the sun and moon pull in the same direction.
What are Neap tides?
(weakest) occur at First & Last Quarter Moons.
Least different between low and high tides.
Define orbit
The path an object, like a planet or moon, takes around another object in space, like the Earth around the sun or the moon around the Earth
Why do eclipses happen so rarely?
The moon’s orbit is tilted 5 degrees relative to earths orbit around the sun
Describe how orbits work
Objects move in curved paths due to gravity pulling them toward a larger object while inertia keeps them moving.
Period: Time it takes to complete a full orbit.
Velocity: Speed at which an object moves around another object in space
What causes the seasons?
Earth’s tilt causes different parts to receive more or less sunlight during the year. The hemisphere experiencing summer is tilted more directly toward the sun.
What are the effects of Earth’s tilt?
The Earth’s tilt changes the day’s length because it affects the length of the sun’s path across the sky. The tilt affects the sun’s height in the sky.
Objects appear to move because the Earth rotates on its axis, making the sun, moon, and stars seem to rise and set.
Influences solar energy reaching Earth. The tilt causes the Earth to receive varying amounts of sunlight throughout each year.
What is the solstice?
Longest and shortest days (summer and winter). Day when the sun appears farthest north is the summer solstice in the Northern Hemisphere and winter solstice in the Southern Hemisphere
What is the equinox?
Equal day and night (spring and fall). Neither hemisphere is tilted toward the sun. About 12 hours of day and night.
What causes the moon phases?
Caused by sunlight reflecting off different portions of the Moon. As the moon goes around the Earth the same side of the moon always faces the Earth. 50% of the moon is always illuminated by the sun. The portion of the moon that is visible from Earth changes, and these are the lunar phases.
What are the moon phases? (make sure you can identify them in pictures)
New, Waxing Crescent, First Quarter, Waxing Gibbous, Full, Waning Gibbous, Last Quarter, Waning Crescent.
