ellipse

2. Kepler’s first law states that each planet's orbit is this shape around the Sun.
6. The shape of planetary orbits, as discovered by Kepler.
8. The astronomer who first proposed that planets orbit the Sun in a circular mot
9. Kepler’s mentor who tasked him with studying Mars’s orbit.
11. The longest axis of an ellipse.
13. The plane on which all planetary orbits are aligned

1. The model of the solar system that places the Sun at the center
3. The unit used to express the semi-major axis in Kepler's third law
4. The shortest axis of an ellipse
5. Kepler’s second law states that the imaginary line joining a planet and the Sun sweeps equal areas in equal _____
7. The term used to describe the flattening of an ellipse.
10. Kepler’s third law states that the squares of planets' orbital periods are proportional to the cubes of their _____ major axes.
11. The planet with the most elliptical orbit.
12. A point at which the sum of distances from any point on an ellipse remains constant.