Changes in speed do affect the size of an orbit due to the principles of conservation of angular momentum. When an orbiting object, like a hypothetical asteroid, is teleported outward or inward, its velocity must adjust to maintain a stable orbit, which can result in changes to its orbital period. The discussion highlights that teleportation does not conserve angular momentum, complicating the relationship between speed and orbit size. Additionally, the effects of changing speed or distance can be analyzed using Kepler's laws and the vis viva equation, which relate velocity and orbital radius. Overall, the interplay between speed and orbital distance is crucial for understanding orbital mechanics.