Across
- 1. collection of billions of stars held together by gravity
- 5. spherical shell of icy objects surrounding the solar system, contains long period comets
- 7. a belt of icy objects including short period comets outside Neptune's orbit
- 8. nuclear ________ is how stars release energy by light and heat
Down
- 2. space rocks found in a belt outside the orbit of Mars
- 3. leftovers from start of solar system, minerals, gas, ice , dust
- 4. natural satellite that orbits planets
- 6. these planets do not have a clear path around sun
- 9. sphere of gas held together by gravity