S/2018 J 4

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/s-2018-j-4

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. Who discovered S/2018 J 4?Telescopic observation
2. What is the astronomical designation?S/2018 J 4
3. What is the parent body?Jupiter
4. How far away is S/2018 J 4 from Jupiter?It orbits roughly 20.7 million kilometers (about 12.9 million miles) from the center of Jupiter. That is a very large distance compared to the big Galilean moons.
5. Why does S/2018 J 4 have a strange, tilted orbit?Its orbit is highly inclined and eccentric, meaning it is tilted and not a perfect circle. This shape shows that it was likely captured by Jupiter’s gravity instead of forming right next to the planet.

Irregular Moon: A moon with a distant, eccentric, and often highly inclined orbit, typically captured.
Semi-major Axis: The average distance of an object from the center of the body it orbits.
Orbital Perturbation: A change in an orbit caused by the gravitational influence of other bodies.
Gravitational Capture: The process by which a celestial body's gravity traps another object into orbit.