Lesson 25
Orbital Dynamics, Part II

 Name:faculty Section:M2 Start Time:12:33:57 Instructor:pate Course:355

1) Suppose you are called on the telephone by someone hosting a quiz show. Their topic du jour is space travel. In particular, they're thinking about satellites. You're in luck!

You can win the prize if you can explain to them how one calculates the Dv required

• to get from (i) a circular orbit into (ii) an elliptical orbit about the same central object, and
• to get from (i) the elliptical orbit to (ii) a new circular orbit still about the same central object.
You can assume the quiz show host has a technical background and has had 110/215 type physics, but not that he/she has either taken a 355-type course or has a 355-type book at his/her disposal. What will you say?

2) Many of our satellite missions take advantage of gravitational assists or "fly-by's" to change the path and speed as a result of encounters with other objects.

How does the relative motion of the small object and the large object matter? In particular, sometimes you can gain speed, and sometimes you can lose speed. Under what conditions do these results occur?

Look at the physlet (see below) and try to estimate (hint: mouse-down!) the change in speed of the smaller red object in each of the cases. What do you conclude?

Note: To obtain your answer, you'll need to give another Physlet page a try. Important: This page will open in a NEW window, so you'll need to come back to THIS window (using the taskbar) to submit your preflight. Once again, if the physlet page does NOT load properly, please tell me what happens, including any error messages it displays, in the comments box below. Thanks. Click this link to get to the physlet page.

3) What question(s)/topic(s) would you most like to have addressed if we take part of our class time to review/answer questions before the GR?

Below is a space for your thoughts, including general comments about today's assignment (what seemed impossible, what reading didn't make sense, what we should spend class time on, what was "cool", etc.):

You may change your mind as often as you wish. When you are satisfied with your responses click the SUBMIT button.

I received no help from anyone on this assignment.
I received help from someone on this assignment (document in comments section).