Celestial navigation

High school (ages 12+)
Geography

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/celestial-navigation

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the core calculation method?Spherical trigonometry applied to measured celestial altitudes and precise time
2. What is the historical impact?Enabled global exploration, trade routes, and the mapping of the world
3. How does a sextant help sailors?A sextant is a tool that lets sailors measure the angle between a star and the horizon. This angle, called the altitude, is used with time and charts to draw a line that shows where the ship could be.
4. Why do sailors need a chronometer?A chronometer is a very accurate clock that tells the exact time at Greenwich. Knowing the time lets sailors calculate longitude, which is the east‑west position on Earth.

Spherical Trigonometry: A branch of mathematics dealing with triangles on the surface of a sphere.
Nautical Almanac: An annual publication containing astronomical data for celestial navigation.
Line of Position (LOP): A line on a chart on which a vessel's position is known to lie.
Greenwich Mean Time (GMT): The time at the prime meridian (0 degrees longitude), used as a standard for timekeeping.