Across
- 4. The farthest point from Earth in a satellite's orbit (Earth-centric version of aphelion).
- 6. The mathematical operation applied to the orbital period in Kepler's Third Law (T²).
- 7. The time it takes a planet to complete one full orbit around the Sun. Area The space swept out by an imaginary line connecting a planet to the Sun over time. Velocity: The speed of a planet in a given direction, which constantly changes throughout its orbit.
- 8. A measure of how much an orbit deviates from a perfect circle.
- 9. The attractive force between masses that keeps planets locked in their orbits.
- 11. Tycho Brahe, the Danish astronomer whose accurate observational data Kepler used.
- 13. The oval-shaped geometric path that a planet follows around the Sun.
- 14. The star at the center of our solar system that sits at one focus of every planetary orbit.
- 16. One of two central points used to define an ellipse; the Sun occupies one of these.
- 17. A celestial body moving in an elliptical orbit around a star.
Down
- 1. An artificial or natural body that orbits a planet, also following Kepler's laws.
- 2. Johannes Kepler, the German astronomer who formulated the three laws of planetary motion.
- 3. The plural form of focus.
- 5. The mathematical operation applied to the semi-major axis in Kepler's Third Law (a³).
- 10. The distance from the center of the Sun to the position of the planet.
- 12. Half of the longest diameter of an ellipse, used to calculate orbital periods.Perihelion The point in a planet's orbit where it is closest to the Sun and moving fastest. Aphelion The point in a plane's orbit where it is farthest from the Sun and moving slowest. Perigee The closest point to Earth in a satellite's orbit (Earth-centric version of perihelion).
- 15. The longest diameter of an ellipse, running through both foci.