UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
Does the solar system ever end and if so how ? Is there a wall or does it just go on forever?
Question Date: 2000-03-03
Answer 1:

The solar system must end somewhere (why?) It is difficult to define exactly what you call the "end" though. Does it end where the stuff orbiting the sun ends? Or maybe where the radiation pressure of the sun matches the pressure due to the interstellar medium that surrounds the solar system? How would you define where the solar system ends?

Answer 2:

One way to define the solar system is if bodies within it have a closed orbit around the Sun.

Is another star part of our solar system?We don't know of another star that is moving slowly enough to be in orbit with our Sun, so there must be a limit to the size of the solar system. What would happen to a planet placed halfway between the Sun and the nearest star? Would the planet fall towards the Sun or towards the other star? What if the planet was moving? Does it matter which direction the planet moves?

Try having several people hold a sheet stretched out smoothly. Now have two other people each grab a separate point well separated in the middle of the sheet and pull down to form two depressions in the sheet. Place or gently roll a marble along the hump between the two
depressions. The depressions represent the "gravity well" of each star's solar system. Try different amounts of tension on the sheet generally and on each of the depressions. Does this change in the "gravity" change the size of each "solar system"? How far away from one "star" can you roll the marble without it being captured by the
other "star"? Do you see a wall? Is a wall needed? What happens when you have more than two "stars"?

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use