What phenomenon involves a stationary object appearing to move when staring at it for too long?

The correct answer is autokinesis, which refers to the optical illusion where a stationary light source appears to move when stared at for an extended period of time, especially in low-light conditions. This phenomenon is particularly relevant in aviation, as crew members may encounter it at night or in conditions with limited visual references.

When a pilot or crew member fixates on a single point of light, their eyes can lose the natural reference frame needed to perceive it as stationary, leading to a false perception of movement. This can affect their spatial awareness and orientation, which is crucial for safe navigation and operational efficiency.

Understanding autokinesis is vital as it underscores the importance of maintaining situational awareness and the need for crew training on how to manage visual illusions effectively. In contrast, the other concepts like motion parallax, relative motion, and false horizon involve different aspects of visual perception and spatial awareness but do not specifically address the illusion of motion experienced with a fixed point of light.