Celestial Navigation Example

Silicon Sea, leg 57

In these web pages, I will show an example of celestial navigation, step-by step. I have chosen as my example the sample leg 57 from the sample problem series Silicon Sea

In this sample problem, we start with a boat whose last known position was 51°30.0'S, 80°59.5'W. We have the boat's heading and speed, and the current. After nearly a day of sailing, we take sextant sights on the moon and four stars. The goal of the exercise is to determine the boat's current position.

Tools

For the purposes of this exercise, we need the following items: If you don't have the 1999 Almanac handy, you can visit Omar Reis's awesome web-based almanac

For more resources, see http://www.celestialnavigation.net/

Steps

There are several steps to solving for our current position. Each is handled on its own page:
  1. Use dead reckoning to estimate current position
  2. Prepare a plotting sheet
  3. Compute line of position for Rigil Kentaurus
  4. Compute line of position for Acrux
  5. Compute line of position for Aldebaran
  6. Compute line of position for Peacock
  7. Compute line of position for the Moon
  8. Final plot
  9. Answering the questions in the exercise
  10. Addendum -- solving with calculator instead of tables