Orbits are paths taken by planets, moons, asteroids, spaceships, or other objects in space around an object of larger mass. The orbits of planets and moons may result in eclipses and planetary alignments. These events are often used in fictional worlds as important facets of cult rituals, magical events, or apocalyptic scenarios. Spaceships and other structures are often located in near orbit surrounding a planet, and dangerous situations involving decaying orbits are often featured in fictional narratives.
|Types of Orbit
|Geosynchronous Orbit: An orbit that keeps the satellite or object above the same relative location on the planet below.
|Circular Orbit: An orbit whose path traces a circle.
|Elliptic Orbit: An orbit whose path traces an ellipse.
|Closed Orbit (periodic orbit): An orbit whose path repeats itself.
|Open Orbit (escape orbit): an orbit that will result in the object either crashing into the planet below or escaping its’ gravitational pull.
|Parking Orbit: A temporary orbit.
|Decaying Orbit: An orbit that causes an object to slowly crash into the planet below.
|Graveyard Orbit (junk orbit): An orbit where satellites are moved to at the end of their functional lives.
Objects in different orbits offer worldbuilders a plethora of narrative options, from rescuing a ship, astronauts, or treasure in a decaying orbit to secretly salvaging useful material from a graveyard orbit.
The gravities of two objects (one of which is in circular orbit around the other) will generate Lagrange points that also orbit around the central body. These Lagrange points will remain in the same positions relative to the other two objects and are locations where asteroids and space stations may be found.
A planet or moon with a circular orbit that matches its’ rotational period may be tidally locked. The same side of the planet or moon will always face the central sun, planet, or other object. Our own moon is a real world example of a tidally locked natural satellite.