Orbital Motion Lecture Notes

These flashcards cover key vocabulary and concepts related to orbital motion, including the laws of gravity, orbital characteristics, and specific phenomena involving celestial bodies.

1. Eccentricity

A parameter describing the flatness of an ellipse, ranging from 0 to 1.

2. Perihelion

The point in an orbit closest to the Sun.

3. Aphelion

The point in an orbit furthest from the Sun.

4. Revolution

The motion of an object around the Sun.

5. Rotation

The spin of a body on its axis.

6. Newton's Universal Law of Gravity

The attractive force between two bodies, which keeps objects in orbit.

7. Orbital period (T)

The time it takes for a planet to complete one revolution.

8. Inclination

The angle of a planet's orbit relative to Earth's orbit.

9. Co-planar

Planets that orbit in nearly the same plane.

10. Prograde

The direction of orbit that is the same as the Sun's rotation.

11. Retrograde

A rare orbital direction opposite to the Sun's rotation.

12. Circumbinary planets

Planets that form from a disk around two stars.

13. Nemesis Hypothesis

The theory that a companion star to the Sun could explain cyclic mass extinctions.

14. Gravitation perturbations

Small forces between planets that can affect their orbits.

15. Binary star systems

Systems with two stars orbiting each other, potentially hosting planets.