The Sextant (Escape Plan)

The movie Escape Plan (starring Stallone and Schwarzenegger) is about a man who's been testing federal prisons for their capacity to prevent an escape from their maximum security. He is then recruited by the CIA to test a certain underground prison facility.

In the movie, Breslin (Stallone) ends up creating a sextant to figure out where the prison was located. A sextant is an old astronomical tool used commonly in nautical navigation (celestial navigation). It is a tool used to measure the angular height/ altitude of a star with respect to the horizon. Seafarers had to be familiar with the night sky in order to put the sextant to use. First of all one must locate Polaris, the north star. A common misconception is that Polaris is a really bright star; this however is not true. Being familiar with the patterns of the constellations and knowing which is next to which can help. Of course it helps also if one has a compass to point you in the general direction.

The measured angular height of Polaris will give you the angle of your latitude. As an example, if we were to say that we measure Polaris to be ~13 degrees from the horizon in Manila then we can say that Manila is located at a latitude of 13 degrees.

Stargazer Tricks

Here are some neat stargazing tricks that you can try out:

1. Use RED light. -> red light has lesser strain on your eyes so it is the best color of light you can use to preserve your night vision. Also, most sky maps are designed to be easilly viewed under a red light.

2. Know where you are by finding the north star. -> The north star, polaris can tell you how many degrees you are from the equator. How? Look for Polaris (tail of the little dipper), then determine its angular distance (vertical distance from horizon measured in degrees). The angular distance is the same with your distance in the globe.

3. Recycle to make a quadrant. -> To measure angular distance, an easy tool to use and make is a quadrant. if you buy plastic protractors they usually get broken. Take the broken protractor and take a quarter circle. You can attach this to a piece of cardboard also cut to a quarter circle. Punch a hole in the focus and suspend a weight from the hole. When you view the horizon, look along the 90 deg. line, the weight will fall on the 0 deg. mark giving the 0 deg. angular distance. as you look up the weight slides down giving you the rising angular measurement.

4. Reach for the skies. -> astronomers use arc length to estimate the length of a celestial object. Extend your fist to the sky at arms length. At this distance, your fist length is equal to 10 degrees arc.


Want to share your tricks? email or comment in this blog.