Astronomy Study Guide Review

Only one side of the moon faces Earth because: the moon rotates at the same rate it revolves

Planetary orbits are ______elliptical in shape.

Earth rotates _______counterclockwise_____________________ Earth rotates _______counterclockwise_____________________. Clockwise/counterclockwise.

Describe the difference between aphelion and perihelion, when do they occur? Aphelion- Earth is farthest from the sun. (July 4th) Perihelion- Earth’s is closest to the sun. (January 5th)

What is a solstice. When do they occur What is a solstice? When do they occur? Summer solstice- Longest day of sunlight of the year Winter Solstice- Shortest day of the year

What is an equinox? When do they occur? Equinox- latin for “equal nights” Vernal Equinox- Spring- March 20th Autumnal Equinox- Fall- Sept. 22nd  Center of Sun is in the same plane as the Earth’s equator.

Describe parallax.  Change in an object’s direction due to a change in the observer’s position.

Why do we have winter in the Northern Hemisphere when we are closest to the sun? The tilt of Earth’s axis allows us to have winter when we are closest to the sun.

  What is the name of the theory of how the moon formed?  The Giant Impact Theory

How often does the moon rotate?  One time every 27.3 days.

Describe the difference between apogee and perigee.  Apogee, the moon is farthest from the Earth. Perigee, the moon is closest to the Earth.

Describe the lunar phases.

What is a blue moon? Harvest moon?  Harvest Moon- Full moon closest to the autumnal equinox. Blue Moon- 2 full moons in 1 month  

Describe three geologic features of the moon.  Lunar marias, lunar highlands, craters

Describe the process in which stars get their energy.  Fusion

List the six layers of the sun. Describe each layer. Corona Chromosphere Photosphere Convection Zone Radiation Zone Core

What are sunspots and how long is the sunspot cycle?  Spots on the sun- 11 year cycle

What feature of Earth protects us from the harmful solar winds?  magnetic field

When solar wind interacts with the Earth’s magnetic field it causes _____auroras________________.

Stars are born from __gas________________ and __________dust_____________.

Stars are mainly 2 gases __hydrogen_____________________ and ______helium_________________.

Describe the difference between a light year and an AU.  light year- distance light travels in one year. AU- distance from the Earth to the sun. (150 million km)

The color of the star determines the ____surface temperature_____________________ of the star.

What is the name of the diagram that compares luminosity and temperature? H-R diagram

Stars are born from clouds and dust called a nebula. Draw and label the life cycle of a sun-like star. See next slide. Draw and label the life cycle of a massive star. See next slide

What kind of star is our sun? main sequence.

What is a supernova? Stellar explosion- death of a massive star.

List the five circumpolar constellations. a. Cassiopeia b. Cepheus c List the five circumpolar constellations. a. Cassiopeia b. Cepheus c. Ursa Major d. Ursa Minor e. Draco

List the Jovian planets  Jupiter Saturn Neptune Uranus

List the terrestrial planets  Mercury Venus Earth Mars

Which is the largest planet? Jupiter

Which is the hottest planet? Why? Venus

Describe a comet. What is it made of? Ice, rock, Carbon dioxide other frozen gases

Draw a Venn diagram. What are the similarities and difference of Terrestrial planets and Jovian planets? Rocky Small No rings Gases Large rings

As you travel farther from the sun, explain how the period of revolution changes? Period of revolution increases as you move farther from the sun.