Across
- 5. The classification given to the four outermost planets which retained large amounts of hydrogen, helium, and other light elements in gas form
- 8. The coming together and cohesion of matter under the influence of gravitation to form larger bodies
- 10. area under the rocky layer of crust where magma is hotter than surrounding magma
- 12. plate boundary where oceanic crust descends beneath a plate with thicker crust
- 13. A stream of charged particles radiating outward from the sun at high speed
Down
- 1. the classification given to the four innermost planets composed mostly of metals and silicate rocks
- 2. The giant canyon on Mars approximately 10 times longer and six times wider than the Grand Canyon
- 3. the largest plain, crowned by the largest mountain on Mars
- 4. The process by which hydrogen is converted to helium in the core of a star
- 6. The speed a particle needs to reach to leave a planet's gravity
- 7. source of the Earth's internal energy based on unstable isotopes
- 9. term used to describe venusian tectonics because it is dominated by the rising and sinking of its mantle and crust
- 11. The largest mountain in the solar system