Build a Sextant

In the Disney movie Moana, the
main character uses traditional
Polynesian celestial navigation

techniques to navigate the ocean

Did you know?

Moana measures the altitude of stars in Orion's

Belt using her hands. To measure altitude,

voyagers:

1. Hold their hand with the palm facing

outward and thumb fully extended

touching the horizon.

2. Use each part of their hand to measure a

particular altitude.

Think about it,

what kind of

modern tools do

we use now to

navigate our

world?

That’s right!

GPS

Global Positioning System. It's a

space-based radio-navigation system

that provides users with positioning,

navigation, and timing (PNT) data

We now have so many tools to use for

GPS!!

*Wearable GPS trackers

*Vehicle GPS trackers

*Cell-based GPS

So how did we navigate before the invention

of GPS?

What did we use to travel the ocean for trade

and exploration?

With a Sextant!

What is a

sextant?

A sextant is a navigation tool that measures the angle

between a celestial object ( like the stars)and the horizon to

determine a ship's latitude and longitude

What is longitude and

latitude?

Longitude: is a way to say where a place is on the Earth. Longitude says how far east or

west of the Prime Meridian any place is. It is measured starting from an imaginary

north-south line called the Prime Meridian.

What is longitude and latitude

Latitude: a geographic term that measures how far north or south a

location is on Earth, relative to the equator:

Sextants are still used today, especially for

ocean navigation!

• *Required for big ships

*The Navy reintroduced celestial navigation and sextant use into its

surface ship navigation curricula around 2014.

Let’s build one together!

you need scissors, a straw, string,

and some tape

1. step 1: cut out your

sextant

2. Tape string to the middle of the

flat edge of the protractor. Be sure

to put the tape on the BACK of the

protractor.

Step 3 : Tape the straw along the flat

edge of the protractor.

Step 4 : Tie a weight (i.e., pencil, binder

clip, etc.) to the bottom of the string.

(Put your name on your sextant please)

Now, let’s use our navigation

tools!

We are all going to measure the

distance from where we are sitting

to the extension cords on the

ceiling. Using your sextant, you are

going to look through the straw at

the object first....

Now, let’s use our navigation

tool!
You are going to pick 5 objects

to locate. 1 object in the

classroom, and 4 in the hallway,

( you have to locate one object

away from the school using the

windows in the hall.)

Now we will go out into the hall, please do

not go past the bathrooms or stairs. You will

write down your degrees in the table for your

5 objects

( inside voices in the hall please)

Please stop after day 1 on your paper.