Nadir

High school (ages 12+)
Space & Astronomy

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/nadir

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 gravitational alignment?It aligns with the direction of the local gravitational pull
2. What is the astronomical reference?Essential for defining local vertical and celestial coordinates
3. Why is the nadir different in New York and Sydney?Because the nadir is local to each place, it points toward the center of gravity from that spot, so it changes depending on where you are.
4. How do satellites use the nadir?Satellites often point their cameras or sensors toward the nadir so they can take pictures of the Earth’s surface directly below them.

Nadir: The direction pointing directly below an observer or location, opposite the zenith.
Zenith: The direction pointing directly above an observer or location, opposite the nadir.
Orthogonal: At right angles; perpendicular.
Geodesy: The science of measuring and understanding the Earth's shape, orientation in space, and gravity field.