ASTR 110 M02,M03,M04 - FALL 13 - Holtzman

Review list for final

Study the class notes at http://astronomy.nmsu.edu/holtz/a110/a110notes. Review the assignments. Make sure you understand the big questions, things we talked about that are related to everyday experience:

• How and why do the stars and Sun move in the sky?
• Why do we have seasons?
• Why does the Moon have phases? What are eclipses?
• What is Earth's place in the Universe?
• How do orbits work?
• Why is the sky blue?
• What are nuclear reactions and how do they work in the Sun?
• What is the greenhouse effect?

The final will emphasize issues from the last part of the class (since the second midterm), but will definitely include the important issues from earlier parts of the class as well!

• Understand how the process of science works, including the fundamental concept of how scientific models and theories are based on data, predictions and verification. Understand some hallmarks of good science, and why pseudoscience is fundamentally different from science. Understand the difference between astronomy and astrology.

• 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 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.

• Understand historically how humans have reached the present understanding of motions in our Solar System, e.g., the geocentric and heliocentric models and what observations motivated these models. Understand the contributions of Ptolemy, Copernicus, Galileo, Tycho Brahe, and Kepler.

• Understand Kepler's laws and be able to use them. Know the terminology which comes into Kepler's laws: ellipses, focii of ellipses, semimajor axis, eccentricity, period, astronomical unit.

• Know the objects in the Solar system: Sun, planets, moons, asteroids, meteors, comets, Kuiper belt, planets and dwarf planets. 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 (stars and interstellar matter). Know the main different types of galaxies.

• 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 each other and the implication that the Universe is expanding. Understand the basic ideas and justifications for the Big Bang theory, and how it is a good example of how the process of science works, including prediction and observation of the microwave background, etc.

• Understand rough relative sizes of objects: Sun, planets, stars, Milky Way, galaxies, and relative distances between them. Understand what a scale model is and how they work, and how to apply one.

• Understand how astronomers can measure distances to objects that are so far away using measurment of angles and also by studying brightnesses of objects. Know what parallax and the inverse square law of brightness are. Know some of the units that astronomers use to measure distances: the astronomical unit and units of light travel time (like the light year).

• Understand Newton's laws of motion: law of inertia, force law, and action/reaction. Understand the law of gravity and what the force of gravity depends on. Understand what the different basic forces are. Understand how the law of gravity can be used to calculate the relative strength of gravity at different places, for example, your weight on different planets.

• Understand how Newton's laws can be used to understand orbits, and that Kepler's laws are a natural consequence of Newton's more basic laws about how things move.

• Understand orbits: why objects can go around each other when the force of gravity is an attractive force between the two objects. Understand how our model for the formation of the Solar System leads to the expectation that planets will have initial transverse velocities and thus will orbit the Sun rather than fall into it.

• Understand how masses of astronomical objects are inferred using our understanding of gravity and measurements of motions of objects. In particular, understand how we measure masses of planets and stars. Know ROUGHLY how massive these objects are: e.g., how massive are different planets compared to the Earth, and how massive are different stars compared to the Sun.

• Understand how we measure masses of galaxies, and know why we believe that there is a large amount of dark matter in the Universe.

• Understand the concept of gravitational lensing and qualitatively how it can be used to infer masses of objects. Know what a black hole is.

• Light. Know about the general properties of light, and the different forms that light can take (the electromagnetic spectrum), and how different kinds of light are characterized by different wavelengths or different energies. Know about the different kinds of spectra (continuous, emission line, absorption line) that objects can produce. Understand the types of spectra that different astronomical objects produce (e.g., stars produce absorption line spectra, etc.)

• Understand thermal (blackbody) radiation (continuous radiation from warm dense sources) and how it can be used to infer temperatures of objects.

• Understand the effect of dust in the interstellar matter (and in the Earth's atmosphere) on the colors of starlight. Know why the sky is blue and why the sun can appear to change color between midday and sunset.

• Understand basic atomic structure and how the different elements differ at the atomic level. Understand that atoms move and that the speed of their motion is related to the temperature.

• Understand how emission and absorption lines are produced, and how they are related to orbits of electrons in atoms. Understand how we can observationally determine physical properties by studying emission and absorption lines. In particular, know how we can estimate temperatures and compositions of stars.

• Know that normal matter in the Universe is primarily composed of hydrogen, with some helium, and very little of everything else.

• Understand how the total brightness of stars depends on the temperature, size, and distance of the star. Understand how we can use our previous estimates of temperatures (from colors and/or spectra) and distances (from parallax) to determine sizes of stars. Understand what a HR (color-magnitude) diagram is, and where stars fall in this diagram. Understand the terminology: main sequence, red giant, white dwarf.

• Know what the Doppler shift is, and how we can infer information about the radial velocities of astronomical objects.

• Understand what nuclear reactions are, why they can produce energy, why they require high temperatures, and what nuclear reaction is going on in the Sun.

• Understand basic stages in evolution of stars, including the Sun. Understand the production of heavier elements inside stars and their distribution into space.

• Understand why we are interested in locations where one might be able to find liquid water, and where in the Solar System liquid water might exist, and why.

• Understand qualitatively what affects how hot it will be on planets. Understand external heating by the Sun. In particular, understand the greenhouse effect. Understand internal heating, both from heat left over from planet formation and from tidal heating.

• Understand some of the factors that go into determining the liklikhood that intelligent life might exist in the Universe. Understand some of the recent observations of extrasolar planets.