Near-Earth object

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/near-earth-object

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 orbital definition parameter?Perihelion distance less than 1.3 astronomical units (AU)
2. What is the known NEO population (as of dec 2024)?Over 37,000 near-Earth asteroids (NEAs) and over 120 near-Earth comets (NECs)
3. Why do some space rocks get close to Earth?The Sun’s gravity and the pull from big planets like Jupiter can change a rock’s orbit. These changes can make the rock’s path cross Earth’s orbit, bringing it near our planet.
4. How do scientists find and watch these space rocks?Scientists use telescopes and special surveys to spot new rocks. Once found, they track the rock’s orbit and size to see if it could be a danger.

Astronomical Unit (AU): A unit of length equal to the mean distance between the Earth and the Sun, approximately 150 million kilometers.
Perihelion: The point in the orbit of a celestial body at which it is closest to the Sun.
Potentially Hazardous Object (PHO): An NEO that meets specific size and orbital criteria indicating a potential risk of Earth impact.
Torino Scale: A logarithmic scale used to rate the potential hazard of an NEO based on probability and potential damage.