Review for Exam 2 Chapters 5,6,7,8 PHYS 1050 May, 2002

Purpose This document is a study guide, NOT a comprehensive list of all topics included on the exam. The exam will cover material from both the text, class notes, and lecture demonstrations. SUMMARY and REVIEW AND DISCUSSION at the end of the text chapters are also good sources of information and comprehension assessment.

Equations and Constants F = ma F grav = Gm 1 m 2 /r 2 P 2 = a 3 or (M+m) P 2 = a 3 M = rv 2 /G where M=mass of planet, r=radius of moon’s orbit, v=circular orbit speed circumference of circle = 2  x radius = 2  r diameter = D = 2 x radius OR D = 2r area of circle =  r 2 =  (D/2) 2 volume of sphere = 4/3  r 3 = 4/3  (D/2) 3 density = mass/volume distance = speed x time in a circle light gathering power proportional to area of objective (or D 2 ) angular resolution proportional to wavelength of light studied and inversely proportional to diameter of objective.

Properties of Telescopes –light gathering power proportional to area of primary or (diameter) 2 –resolution as a function of diameter of the objective and the wavelength of light imaged Types of Telescopes and Detectors: –understand advantages/disadvantages of each type reflectors (mirrors, large size) refractors (lenses) space-based telescopes –Earth’s atmosphere interferes with ground based observations –wavelengths absorbed, reflected, transmitted –turbulence radio telescopes infrared, ultraviolet, and high energy telescopes –design of telescope detectors –eye –photographs (chemical recorders) –CCDs (electronic recorders)

Solar System –Age of the solar system: ~ 4.6 billion years old –Know the ordering of the planets from the Sun. –Know which planets are the terrestrial planets, which are the jovian planets, and which fit neither category. –Be aware of and understand the primary differences between terrestial and jovian planets. Use TABLE 6.2 in your textbook. –Know the approximate relative sizes and masses of the planets. Look at the appropriate columns in TABLE 6.1. –Know how the average densities of the planets compare (see "DENSITY" in TABLE 6.1) –Know the approximate rotational period of the planets -- know which are "slow", which are "medium", and which are "fast" rotators. –Understand physical differences between comets, asteroids, and meteoroids. –Know which planets have been visited by spacecraft and on which objects have spacecraft actually landed. Develop a sense of how each planetary exploration mission changed our perspective and understanding of the properties of each planet. for example: What did Magellan add to our knowledge of Venus? What about Viking with respect to Mars ?

Formation of Planetary Systems –List the main features of our solar system that a theory of the formation of the solar system must explain. –Outline the process by which planets are formed as a normal by-product of star formation. Condensation theory –Role of dust –Accretion –Fragmentation –Formation of giant planets –Temperature and distance from the Sun –Differentiation Entire solar system Individual planets –Extra-solar planets Method of discovery Comparison with our solar system

PLANET EARTH –Know the basic “spheres" into which planetary scientists have divided up the Earth: lithosphere, hydrosphere, atmosphere, magnetosphere, biosphere composition, density, temperature trends in each region Interactions between spheres –Know the different regions of the Earth's atmosphere: names, main features, ordering with altitude temperature variation with altitude –Define P-waves and S-waves. What information is derived from studying seismic waves? –Understand the term "plate tectonics". Know what process drives plate tectonics. Know that most geological activity (e.g., earthquakes, volcanoes) is associated with plate boundaries. New crust is created at plate boundaries by upwelling mantle material. Old crust is returned to the mantle in subduction zones. Lighter continental crust "floats" on the more dense crust of the ocean basins. –Know the definition of a "half-life" for a radioactive element. –Know where the Earth's magnetosphere exists and what effect it has on atomic particles blowing past Earth in the solar wind. –Understand the source of the tides and their effect on the the Earth's rotation.

THE MOON –Understand the difference between the highlands and maria on the moon. Which is the older feature? How do we know which is older? –Know that the Moon rotates once about its axis for each orbit about Earth. Understand why this must be true if we see only one side of the moon. How is the Earth-Moon separation changing? Why is it changing? What is the final relative orbital and spin rate for the Earth and Moon? –Know the relative size and mass of the Earth and Moon. –Know the distance to the Moon. –Understand the origin of lunar craters, and their relative distribution on the lunar surface. Are there more craters on the maria or highlands? –Know if the Moon has an atmosphere. –Understand the current concept of the lunar interior. depth of the crust, nature of the Moon's mantle, nature of the Moon's core. –Understand the phases of the Moon as seen from Earth. –Compare spheres of Moon to those of the terrestrial planets.

MERCURY –Mercury is the closest planet to the Sun. –Describe the rotation and orbital period of Mercury. seasons, elliptical orbit, spin-orbit resonance –Describe the surface of Mercury: craters? volcanoes? oceans? Know what is meant by "scarps" on Mercury; how they may have formed. –How is Mercury’s surface different/similar to that of the Moon. –How does the density of Mercury compare to that of the Earth? Moon? –Does Mercury have an atmosphere? magnetic field? Explain. –Does Mercury have a magnetic field? Explain. –Compare the spheres on Mercury to those of other terrestrial planets and Earth’s Moon.