Across
- 5. a force of attraction between objects that is due to their masses and that decreases as the distance between the objects increases
- 6. 5th planet from the sun
- 8. the motion of the axis of a spinning body, such as the wobble of a spinning top, when there is an external force acting on the axis; a slow gyration of Earth's rotational axis relative to its orbit
- 10. A rotating disk of dust and gas that surrounds the core of a developing solar system
- 14. the solar radiation (energy from the sun) that reaches Earth; the rate of delivery of solar radiation per unit of horizontal surface
- 16. the degree of elongation of an elliptical orbit (symbol, e)
- 17. the location within Earth along a fault at which the first motion of an earthquake occurs; one of the two central defining points of an ellipse
- 19. a gas composed of molecules that absorb and radiate infrared radiation
Down
- 1. the path of a body as it moves around another body due to their mutual gravitational attraction
- 2. evaporating readily at normal temperatures and pressures
- 3. an action exerted on a body that tends to change the body's state of rest or motion; force has magnitude and direction
- 4. is a large cloud of gas and dust in interstellar space; a region in space where stars form
- 7. A dawf planet
- 9. a dark area of the photosphere of the sun that is cooler than the surrounding areas and that has a strong magnetic field
- 11. is an oval shape defined by points for which the sum of the distances to two fixed points (foci) is a constant; a circle is an ellipse of zero eccentricity
- 12. the red planet
- 13. a stream of high-speed, ionized particles ejected primarily from the sun's corona
- 15. The big blue planet
- 18. a center line to which parts of a structure or body may be referred