mirages

Mirages are optical phenomena that produce images of distant objects displaced, distorted, or absent due to refraction of light in Earth's atmosphere. They occur when light passes through air layers of varying temperature and density, bending toward or away from the normal as it travels.

Inferior mirages arise over hot surfaces such as roads or deserts. Warm air near the ground creates a strong vertical gradient in refractive index, bending light upward and causing the sky or distant objects to appear below their true position—often seen as shimmering pools or water on a road.

Superior mirages occur when cool air overlies warmer ground or sea. The temperature gradient bends light downward, so an image of distant objects is seen higher and sometimes inverted, such as ships appearing in the sky.

Fata Morgana is a complex, stacked mirage near the horizon that can stretch, tilt, and duplicate objects into multiple, elongated forms.

Looming and other ducting effects arise in strongly stratified atmospheres, where refractive-index gradients lift distant objects above their true location or distort them dramatically.

Origin of the term: mirage comes from the French mirage, from Italian mirare “to look at” or “to wonder at,” reflecting the deceptive nature of the phenomenon.

Mirages are not solid objects; they are perceptual distortions caused by atmospheric stratification and do not involve actual water or distant objects.