Precession (disambiguation)
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Precession
Precession
Precession is a change in the orientation of the rotation axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second Euler angle is constant...

refers to a specific change in the direction of the rotation axis of a rotating object, in which the second Euler angle (angle of nutation
Nutation
Nutation is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behavior of a mechanism...

) is constant

Precession may specifically mean:
  • Precession is the name of one of the Euler rotations
  • Axial precession (astronomy) — the precession of the Earth's axis of rotation (also known as the "precession of the equinoxes"), or similar
  • de Sitter precession — a general relativistic correction to the precession of a gyroscope near a large mass such as the Earth
  • Larmor precession
    Larmor precession
    In physics, Larmor precession is the precession of the magnetic moments of electrons, atomic nuclei, and atoms about an external magnetic field...

     — the precession of the magnetic moments of electrons, atomic nuclei, and atoms about an external magnetic field
  • Lense-Thirring precession
    Lense-Thirring precession
    In general relativity, Lense–Thirring precession or the Lense–Thirring effect is a relativistic correction to the precession of a gyroscope near a large rotating mass such as the Earth. It is a gravitomagnetic frame-dragging effect...

     — a general relativistic correction to the precession of a gyroscope near a large rotating mass such as the Earth
  • Precession (mechanical)
    Precession (mechanical)
    Precession is the process of a round part in a round hole rotating with respect to that hole because of clearance between them and a radial force on the part that changes direction. The direction of rotation of the inner part is opposite to the direction of rotation of the radial force. Fretting...

     — the process of one part rotating with respect to another due to fretting between the two
  • Thomas precession
    Thomas precession
    In physics the Thomas precession, named after Llewellyn Thomas, is a special relativistic correction that applies to the spin of an elementary particle or the rotation of a macroscopic gyroscope and relates the angular velocity of the spin of a particle following a curvilinear orbit to the angular...

     — a special relativistic correction to the precession of a gyroscope in a rotating non-inertial frame


Precession can also refer to change in the direction of an axis other than an axis of rotation:
  • Apsidal precession
    Apsidal precession
    In celestial mechanics, perihelion precession, apsidal precession or orbital precession is the precession of the orbit of a celestial body. More precisely it is the gradual rotation of the line joining the apsides of an orbit, which are the points of closest and farthest approach...

    , perihelion precession, or orbital precession, the rotation of the orbit of a celestial body

See also

  • Axial tilt
    Axial tilt
    In astronomy, axial tilt is the angle between an object's rotational axis, and a line perpendicular to its orbital plane...

    , also called axial inclination or obliquity, is the inclination angle of a planet's rotational axis in relation to a perpendicular to its orbital plane
  • Conventional International Origin
    Conventional International Origin
    Conventional International Origin is a conventionally defined reference axis of the pole's average location over the year 1900.Polar motion is the movement of Earth's rotation axis across its surface. The axis of the Earth's rotation tends, as the axis of a gyroscope, to maintain its orientation ...

     is a conventionally defined reference axis of the pole's average location over the year 1900
  • Great year
    Great year
    The Great Year is an archaic cosmological conception, found in different cultures, which acquired new interpretations with the development of astronomical knowledge In the Western tradition Plato has been the main source for the idea, so it was also frequently called 'Platonic year'...

    , also known as a Platonic year or Equinoctial cycle, is the time required for one complete cycle of the precession of the equinoxes
  • Nutation
    Nutation
    Nutation is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behavior of a mechanism...

     is a slight irregular motion (etymologically a "nodding") in the axis of rotation of a largely axially symmetric object
  • Polar motion
    Polar motion
    Polar motion of the earth is the movement of Earth's rotational axis across its surface. This is measured with respect to a reference frame in which the solid Earth is fixed...

    is the movement of Earth's rotation axis across its surface
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