ASTR 110 M04,M05,M06 - FALL 09 - Holtzman

Review list for first midterm

• Understand what a scientific theory is, and how data is used to constrain scientific theories. Understand the difference between astronomy and astrology.

• Know the objects in the Solar system: Sun, planets, moons, asteroids, meteors, comets. Know what a shooting star is. Understand the concept of density and how we can use it to get some information about the composition of planets.

• Know how the Sun is one of many stars that make up the Milky Way galaxy; know about the variety of stars in the Galaxy. Know what shape the Galaxy is, how we know this, and what the Milky Way contains. Know the main different types of galaxies.

• Understand rough relative sizes of objects: Sun, planets, stars, Milky Way, galaxies, and know what each of these objects is. Understand what a scale model is and how they work. Understand how astronomers can measure distances to objects that are so far away. Know what a light year and an astronomical unit is.

• Understand the motions of objects in the Universe: planets around the Sun, stars moving inside of galaxies. Understand the observation that galaxies all appear to be moving away from us and the implication that the Universe is expanding. Understand the basic ideas and justifications for the Big Bang theory.

• Understand motions of objects in the sky as seen from Earth, which result from a combination of our motion (reflex) and the intrinsic motion of the object. Understand revolution and rotation of planets. Understand apparent motion of stars, Sun with respect to the stars, and planets with respect to the stars. In particular, understand day and night and the path of the Sun and stars through the sky at different times of year. Understand parallax and how it is used to measure distances to stars.

• Understand how the rotation axis of the Earth is tilted with respect to its plane of revolution. Understand and be able to clearly formulate the reason we have seasons.

• Understand the orbit of the Moon. Understand the reason that the Moon has phases, and how the phases are related to the time of day/night when the Moon is seen from Earth. Understand what solar and lunar eclipses are and why they don't occur every month.

• Understand the motions and appearances of the planets. Be able to figure out whether planets have phases when you look at them. Know what retrograde motion is.