Lunar and Solar Eclipses

Question 1: Why is an eclipse (lunar in this case) not possible at this time?

Question 2: What is the phase of the Moon during a solar eclipse? Hint: Zoom in for a closer view of the Moon.

Question 3: What is the phase of the Moon during a lunar eclipse?

Question 4: The lunar eclipse of June 26, 2010 is only partial because:

Question 5: The date of this total solar eclipse is:

Question 6: Which one of the following statements about this eclipse is correct?

Precession and Nutation

Question 1: What is the precession period of the Earth's spin axis?

Question 2: What is significant about the diameter of the precession circle?

Question 3: At what time in the past was Vega the North Star?

Question 4: When Hipparchus made his observation in the second century BC, in what constellation was the Vernal equinox in?

Question 5: What is the period of nutation?

Our Star, the Sun

Question 1: Approximately how long does it take for the Sun to complete one rotation?

Question 2: Press the Run Time Forward button and observe the sky's motion. Where on the Sun are you located?

Question 3: Use the Angular Separation Tool to measure the distance between the Sun and some of its neighbors. About how far away are our neighboring stars?

Question 4: Sometimes the solar images appear smooth and featureless. What does this tell us about the Sun?

The Solar Neighborhood

Question 1: How many of the stars visible are within ten light years of the Sun?

Question 2: Use the Angular Separation Tool to list these stars in order of increasing distance from the Sun.

Question 3: What is the name of that star?

The Hertzsprung-Russell Diagram

Question 1: Which of the following stars is a red giant (usually class K or M)?

Question 2: Which of the following stars is not a main sequence star?

Question 3: Which characteristics best describe the star Antares?

Question 4: Which of the following stars is a class K star with an absolute magnitude of about 5?

Planetary Orbits and Configurations

Question 1: The sidereal period of Mercury is:

Question 2: When is the next superior conjunction of Venus?

Question 3: The synodic period of Mercury is:

Question 4: What is the length of Jupiter's sidereal period?

Question 5: What is the length of Jupiter's synodic period?

Johannes Kepler and Elliptical Orbits

Question 1: What is the length of the major axis of Mars' orbit?

Question 2: What is the sidereal period of Mars using Kepler's Third Law?

Question 3: On average, how far would Mars have to be from the Sun to have an orbital period of 10 years?

Gallileo Strengthens the Heliocentric Model

Question 1: What is the phase of Venus?

Question 2: What is the approximate angular diameter of Venus when it is a very slim crescent?

Question 3: Based on your answer in Question 2, which model do your observations support?

Question 4: Why did these observations persuade Galileo that the geocentric view of Ptolemy was wrong?

Size and Scale of the Solar System

Question 1: The four inner planets of the solar system in order of distance from the Sun are:

Question 2: What do the four terrestrial planets have in common?

Question 3: What is interesting about the status of Ceres in the Solar System?

Question 4: The four outer planets of the solar system in order of distance from the Sun are:

Question 5: What do the four terrestrial planets and the four gas giant planets have in common?

Question 6: What is the approximate distance in AU between the Sun and the farthest gas giant planet? Use the Angular Separation Tool cursor tool to measure distances.