Anomaly may refer to:

Astronomy and celestial mechanics

  • In astronomy, an anomaly of an elliptical orbit, generally measured with respect to an apsis, usually the periapsis
  • Eccentric anomaly, an intermediate value used to compute the position of a celestial object as a function of time
  • Flyby anomaly, an unexpected energy increase during the flybys of the Earth by various satellites
  • Mean anomaly, a measure of time in the study of orbital dynamics
  • Pioneer anomaly, the observed deviation of the trajectories of some unmanned space probes, and especially Pioneer 10 and Pioneer 11
  • South Atlantic Anomaly, an area where the Earth's inner Van Allen radiation belt comes closest to the Earth's surface
  • True anomaly, the angle between the direction of periapsis and the current position of an object on its orbit
  • Anomalous precession, another term for "apsidal precession"

Natural sciences


  • Congenital anomaly, popularly referred to as a birth defect, a disorder present at birth, the result of an inherited gene mutation, an error during morphogenesis or fetal development, or an environmental factor
    • Physical anomaly, a deformation of an anatomical structure
      • Congenital vertebral anomaly, any of several malformations of the spine in animals and infants
      • Collie eye anomaly, congenital, inherited, bilateral eye disease of dogs involving the retina, choroid, and sclera
      • Coronary artery anomaly, congenital abnormality in the coronary anatomy of the heart
      • Ebstein's anomaly, congenital heart defect in which the opening of the tricuspid valve is displaced towards the right ventricle of the heart
      • Uhl anomaly, very rare congenital heart disease with a partial or total loss of the myocardial muscle in the right ventricle
    • Genetic anomaly, a disorder whose ultimate cause is a genetic or chromosomal mutation
    • Chromosome anomaly, a disorder whose ultimate cause involves a structural error in a chromosome or an atypical number of chromosomes
  • Teratology, the study of all developmental anomalies


  • Anomaly (physics), a failure of a symmetry of a theory's classical action
  • Conformal anomaly, a quantum phenomenon that breaks the conformal symmetry of the classical theory
  • Chiral anomaly, an anomalous nonconservation of a chiral current
  • Gauge anomaly, the effect of quantum mechanics that invalidates the gauge symmetry of a quantum field theory
  • Global anomaly, an anomaly in quantum physics
  • Gravitational anomaly, an effect in quantum mechanics that invalidates the general covariance of some theories of general relativity
  • Mixed anomaly, an effect in quantum mechanics
  • Parity anomaly, an anomaly that is associated with parity
  • Konishi anomaly, the violation of the conservation of the Noether current associated with certain transformations
  • Anomalons, some odd particle interactions that are seen in some high-energy physics
  • Anomalous dispersion (optics), when the speed of an electromagnetic wave increases with increasing frequency

In science fiction