Question

challenge 1 - unlock the laws of motion
complete this challenge to activate the module’s autonav system.
solve 3 riddles connecting planetary motion to newton’s 3 laws
1
i keep the planets in their flight,
no push or pull, yet still they glide.
in endless paths they spin and sway,
what force resists the change, i say?

Explanation:

The riddle is about a force that resists change in motion, connecting to planetary motion and Newton's laws. Newton's First Law (Law of Inertia) states that an object in motion stays in motion (or at rest) unless acted upon by a net external force. Inertia is the property (or "force" - conceptually, though inertia is a property, the riddle's wording implies the force - related concept here is inertia) that resists changes in an object's state of motion. Planets moving in their paths have inertia that keeps them moving unless a force (like gravity, but the riddle is about the resistance to change) acts. So the answer relates to inertia.

Answer:

Inertia (or the concept related to Newton's First Law of Inertia, as the riddle asks for the force - like entity resisting change, and inertia is the property that resists changes in motion, fitting the riddle's description of keeping planets in flight without push/pull and resisting change in their paths).