Planets beyond Neptune

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/planets-beyond-neptune

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. How heavy is Planets beyond Neptune?Roughly 5 to 10 Earth masses for the hypothetical 'Planet Nine'
2. What is the primary detection method?Inferring gravitational influence on the orbits of extreme Trans-Neptunian Objects (eTNOs)
3. What is Planet Nine?Planet Nine is a big, unseen planet that scientists think might be several times the mass of Earth. It could be pulling on faraway objects in our solar system.
4. Why do scientists think there might be planets beyond Neptune?Some very far objects in space have orbits that line up in a way that is very unlikely if only the known planets were there. A hidden planet could be causing that.

Extreme Trans-Neptunian Object (eTNO): Objects in the outer solar system with very large semi-major axes and perihelia beyond Neptune's influence.
Gravitational Scattering: A process where gravitational interactions between celestial bodies cause significant changes in their orbits.
Protoplanetary Disk: A rotating disk of dense gas and dust surrounding a newly formed star, from which planets form.