ASTR 220 - Collisions in Space

Homework 1 (12 points)
Due Tuesday February 15 at the beginning of class

Homework is due at 11AM on the lecture date indicated on the syllabus. Homework handed in after 11AM on the due date will be considered late (a 2 point deduction). Homework turned in after the due date will lose additional points, but partial credit is better than none at all. Late homeworks will NOT be accepted after graded homeworks have been returned.

Homework MUST be neat, meaning typed, word-processed, or very neatly hand written. We must be able to read and understand your homework for you to receive full credit. SHOW your calculations on any problems and JUSTIFY written answers - `yes' or `no' is not adequate. Do NOT COPY from the book or the Web. This is plagiarism and violates the University honor code. Though readings in the book may be the basis of your answer, it is important to phrase all answers in your own words. Do NOT COPY from a fellow student. This is academic dishonesty. You may discuss homework with friends, but the final product must be your own work.

If you make use of references other than the textbooks or class handouts, include the reference information (book title & author; WWW URLs) at the end of your assignment. The University's honor code will be enforced. See page 36 of the Schedule of Classes.

Homework 1 Questions:

  1. Comets:
    Describe the orbit of a typical comet. Relatively speaking, how much time does it spend near to and far from the sun? What happens as a comet nears the sun that sometimes makes it visible?

  2. Observed Crater Densities:
    Satellites (moons) and planets with solid surfaces show great variation in the number of craters that are visible. Describe the processes which can modify a surface which started out with many craters when the solar system was young (4 billion years ago).

  3. Make use of the WWW tool Astronomical Distances to answer the following questions: