Astronomy Final Review

Geocentric Model --Earth is in the center of the system and everything revolves around it.

Heliocentric Model --Sun is located at the center of the system. --The orbit of each planet is an ellipse with the sun at one focus.

Finding the eccentricity of an ellipse Foci- the two points at the center of the ellipse Major Axis- the distance across the center of the ellipse distance between foci Eccentricity= length of major axis

Find the eccentricity of this ellipse =distance between foci length of major axis = 3.8 cm 7.7 cm =.494

Rotation Think SPINNING 360°, 24 hours Coriolis Effect– winds deflect to the right in the northern hemisphere Foucault Pendulum—changes the direction of swing of the pendulum

Revolution The orbiting of the Earth around the Sun 360°/365 days = ~1° per day The Earth’s axis is always pointed at the same place

Seasons of the Year Earth revolves around the Sun Earth is tilted/inclined on its axis 23.5° Earth’s axis is always pointed in the same direction

September 21 st (Fall) March 21 st (Spring) J u n e 21 st D e c e m b e r

Phases of the Moon Caused by the Moon’s revolution around Earth and reflection on Sun The moon revolves at the same speed that it rotates so we are always looking at the same face of the moon.

Moon’s Revolution 1 month or 29.5 days Moon’s Rotation Rotation equals its revolution

E C L I P S E S Lunar Eclipse Solar Eclipse

1. Winter 2. Spring 3. Summer 4. Fall Earth is farthest from the Sun during the Northern Hemisphere’s summer, and Earth is closest to the Sun during the Northern Hemisphere’s winter. During which season in the Northern Hemisphere is Earth’s orbital velocity greatest?

1. the Moon spins on its axis 2. Earth spins on its axis 3. the Moon travels in an orbit around Earth 4. Earth travels in an orbit around the Sun Surface ocean currents curve to the right in the Northern Hemisphere because

1. redshift of light from distant galaxies 2. apparent shape of star constellations 3. presence of volcanoes on Earth 4. presence of craters on Earth’s Moon The Big Bang Theory, describing the creation of the universe, is most directly supported by the

1. A 2. B 3. C 4. D Which lettered arrow represents the motion that causes the Moon to show phases when viewed from Earth?

Which graph best represents the force of gravity between Earth and the Sun during one revolution of Earth around the Sun? A. C. D. B.

The diagram below shows the Moon orbiting Earth, as viewed from space above Earth’s North Pole. The Moon is shown at eight positions in its orbit. Spring ocean tides occur when the difference in height between high tide and low tide is greatest. At which two positions of the Moon will spring tides occur on Earth? A. 3 and 7 B. 2 and 6 C. 1 and 5 D. 4 and 8

1. Pluto 2. Mercury 3. Saturn 4. Mars Which planet has an orbital eccentricity most like the orbital eccentricity of the Moon?