Autokinetic effect

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The autokinetic effect (also referred to as autokinesis) is a phenomenon of visual perception in which a stationary, small point of light in an otherwise dark or featureless environment appears to move. It was first recorded by a Russian officer keeping watch who observed illusory movement of a star near the horizon[citation needed]. It presumably occurs because motion perception is always relative to some reference point. In darkness or in a featureless environment there is no reference point, so the movement of the single point is undefined. The direction of the movements does not appear to be correlated with the involuntary eye movements, but may be determined by errors between eye position and that specified by efference copy of the movement signals sent to the extraocular muscles. Several researchers, including Richard Gregory, have shown that autokinesis occurs when no eye movements are recorded.[citation needed] Gregory has suggested that with lack of peripheral information correcting movements that prevent eye movements due to muscle fatigue are wrongly interpreted as movement of the light.[citation needed]




In literature[edit]

An evocative passage appears in H. G. Wells' novel The War of the Worlds. Although Wells ascribes the apparent "swimming" of the planet to telescope vibration and eye fatigue, it is likely that the autokinetic effect is also being described:

In aviation[edit]

The effect is well known as an illusion affecting pilots who fly at night. It is particularly dangerous for pilots flying in formation or rejoining a refueling tanker at night. Steps that can be taken to prevent or overcome the phenomenon include:

  • Shifting your gaze frequently to avoid prolonged fixation on light sources.
  • Attempting to view a target with a reference to stationary structures or landmarks.
  • Making eye, head, and body movements to eliminate the illusion.
  • Monitoring the flight instruments to prevent or resolve any perceptual conflict.

In combat[edit]

In his book documenting the opening stages of the second Gulf War from his position embedded with the 1st Marine Reconnaissance Battalion, Evan Wright documents an incident during which, at night in the Iraqi desert, the marines observed the lights of a town approximately 40 kilometers away. These lights appeared to be moving and were suspected of belonging to a large combat force moving out to attack the marines. An airstrike was called in on the estimated position of the lights—estimated to be around 15 kilometers away—which resulted in no enemy assets being destroyed. It was later suggested by Major Shoup of the battalion that this misidentification was a result of autokinesis. In the HBO mini-series based on the book, this information was imparted to the viewer by the character of Sergeant Brad Colbert, who had correctly deduced that it was a town in both versions.

Night fighter and night bomber crews during the Second World War reported encounters with mysterious aerial phenomena, nicknamed foo fighters, which may have been caused by autokinesis or a similar effect.

See also[edit]


  • Schweitzer, G. (1857). Über das Sternschwanken. Bulletin de la Société impériale des naturalistes de Moscou. 30: 440-457; 31: 477-500. Source: Skeptic, Volume 17. No. 2 2012, pages 38–43.
  • Generation Kill by Evan Wright. (2005) ISBN 0-552-15189-0 Chapter 17, Page 236.