History of Astronomy
Copernicus proposed the ________ Model, which places the _______ at the center of the Solar System.
Heliocentric, Sun
Seasons are caused by what?
The Earth's tilt (23.5 degrees)
During a quarter moon, how much of the moon is illuminated?
50%
Gravity is an ________ force, which means it _____ objects toward more massive objects.
Attractive, pulls
______ is the spinning of a planet on its axis?
Rotation
A planet's orbital speed will be fastest when it is nearest the sun, and slowest when furthest from the sun.
What are Solstices? When do they occur?
The longest day and night of the year, marking the start of Summer and Winter Respectively. The summer solstice occurs on June 21-22, and the winter solstice is December 21-22
When the Earth is between the Sun and Moon, what phase are we seeing?
Full Moon
An object at rest will stay at rest. An object in motion will stay in motion unless acted upon by an _______ force.
Unbalanced
Explain the difference between Revolution and Orbit
Revolution is the act of one object rotating around another. An orbit is the invisible path an object takes around another.
What important discovery did Galileo make that would confirm that the Heliocentric Model is correct?
That Venus has phases, similar to the Moon
The Vernal Equinox (March 21-22) marks the beginning of Spring in which Hemisphere?
The Northern Hemisphere
Explain why eclipses do not happen 2x a month?
The moon's orbit is tilted relative to Earth by 5 degrees, meaning it is often too high or too low to even cast a shadow onto the Earth, or be in Earth's shadow
Gravity and Inertia
Define equinox and state when they occur.
The days of equal sunlight and darkness when the Earth is neither tilted toward nor away from the sun. They occur on March 21-22 and September 21-22
What Model did Brahe propose? Explain what this means.
Modified Geocentric model; Earth at the center of the Solar System, the Sun orbits Earth, and every other planet orbits the sun
What season would you expect to see the Sun most north of the Equator?
Summer
14-15 Days
According to Einstein, space-time is distorted by Gravity wells. Which object in our solar system creates the largest gravity well?
The Sun (makes up about 99.9% of the mass in the entire Solar System)
Define Lunar Maria.
Latin for sea, they are the large, smooth areas on the Moon formed by hardened Basalt lava flow
List the Historical figures in order:
Galileo, Copernicus, Brahe, Kepler, Newton, Ptolemy, Einstein
Ptolemy, Copernicus, Brahe, Galileo, Kepler, Newton, Einstein
When would the Earth receive equal amounts of sunlight and darkness?
On Equinoxes: Spring (Vernal) and Fall (Autumnal)
True or False: Earth's shadow is responsible for the phases of the moon. Explain your answer.
False: The shadow of Earth is responsible for eclipses. The phases are caused by the angle of light cast by the Sun relative to our position to the Moon
If you were to increase the Mass of one object in a 2 object system by a factor of 8X, what would happen to the force of gravity between them? What if you were to increase the distance by 7x?
For distance, force gravity decreases to 1/49 its original strength.
If somebody's mass is 130Kg on Earth, what would their mass be on Uranus?
Hint: Earth's Acceleration = 9.8ms/s Uranus acceleration = 8.87ms/s
Their mass would remain 130Kg MASS IS MASS