Spring '98 HOMEWORK



  1. (A) What is the estimated age of the universe?
    (B) What is the estimated age of the solar system?
    (C) What constitutes the solar system?

  2. (A) What are the two major constituents of the sun?
    (B) What is the solar constant? What two types of radiation contribute most to solar constant?

  3. Draw and label the internal (i.e. below the photosphere) structure of the sun. Briefly describe the physical processes occurring in each zone.

  4. What are granules and supergranules? Where are they seen?

  5. Draw and label the solar atmosphere and describe the differences between each zone. What is the most puzzling aspect of the solar atmosphere?

  6. What do we mean by active sun and what is the cause of it?

  7. Briefly describe what a prominence is and how it is different from a filament.

  8. What are flares and how do we classify them? What are the phases of a flare?

  9. (A) What are sun spots?
    (B) What is the solar cycle?
    (C) What is the butterfly diagram?

  10. Describe two methods that geologists use to get information about the internal structure of planets.

  11. Draw and label the internal structure of the Earth. Briefly describe the properties of each region. Why is the inner core solid but the outer core liquid?

  12. What are the lithosphere and asthenosphere?

  13. What causes the Earth to have a dynamic geology? Explain briefly.

  14. What is the Earth's magnetic field strength at radial distance of 1.5RiE (Earth radii) and co-latitude of 20°? What are the vertical and horizontal components? Note that µ=0.31 Gauss R3E.

  15. What L value corresponds to invariant latitude of 70°, 50°, and 10°?

  16. What are the two major atmospheric constituents at altitudes below 100 Km?

  17. Assuming a one-dimensional hydrostatic equilibrium, derive the variation of atmospheric pressure as a function of height. Assume a uniform mean molecular mass and temperature.

  18. Describe the properties of temperature regimes in the atmosphere. What gives rise to the observed temperature profile?

  19. What is the difference between the homosphere and the heterosphere?

  20. What is the exosphere?

  21. Why does the ozone layer form only at the top of the stratosphere?

  22. An electron with parallel energy of 10Mev and a perpendicular energy of 10Mev at the magnetic equator moves along the L=5 magnetic field line. What are parallel and perpendicular energies of the electron at a latitude of 20°, assuming that the first adiabatic invariant and the total kinetic energy are conserved?

  23. Given that the change in the solar wind velocity with distance from the sun is given by:
    Plot the corresponding four classes of solutions and discuss which one corresponds to the actual solar wind solution.

  24. Assuming a constant solar wind velocity of 400Km/s and a density of 10 particles per cm3 at 1 Au, what is the solar wind density at Jupiter?

  25. Assuming a radial magnetic field strength of 4 Gauss at the sun's surface and an expansion velocity of 400 Km/s, what is the radial and the azimuthal strength of the solar wind magnetic field at the Earth's orbit (theta = pi/2) ? Note that the angular velocity of the sun is w = 2.7 x 10-6 radians/sec.

  26. How does an active comet interact with the solar wind and why is the interaction region so large?

  27. How many tails does a comet have? Explain their origin.

  28. Which of the cometary tails are observed to disconnect and what is the most popular theory for such events?

  29. What are black holes and how do we infer their existance?

  30. What evidence exists for other planetary systems?

  31. What is the Oart cloud and how was its existance inferred?

  32. What and where is the great red spot?

  33. Which moon of jupiter was observed by Voyager to be volcanicaly active?

  34. What is the best way to map Venus's surface? Why?

  35. What causes the Earth's magnetic field?

  36. Name a unique characteristic of Uranus.

  37. What are the major differences between the inner planets and the outer planets except for Pluto?

  38. Where were the heavy elements in the universe believed to be formed?




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