KABOOM
Tidal locking
From Wikipedia, the free encyclopedia
Tidal locking results in the Moon rotating about its axis in about the same time it takes to orbit the Earth. Except forlibration effects, this results in the Moon keeping the same face turned towards the Earth, as seen in the figure on the left. (The Moon is shown in polar view, and is not drawn to scale.) If the Moon were not spinning at all, it would alternately show its near and far sides to the Earth while moving around our planet in orbit, as shown in the figure on the right.
Tidal locking (or captured rotation) occurs when the gravitational gradient makes one side of an astronomical body always face another, an effect known as synchronous rotation. For example, the same side of the Earth's Moon always faces the Earth. A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This causes one hemisphere constantly to face the partner body. Usually, at any given time only the satellite is tidally locked around the larger body, but if the difference in mass between the two bodies and their physical separation is small, each may be tidally locked to the other, as is the case between Pluto and Charon. This effect is employed to stabilize some artificial satellites.
Contents
[hide]
1 Mechanism
1.1 Tidal bulges
1.2 Bulge dragging
1.3 Resulting torque
1.4 Orbital changes
1.5 Locking of the larger body
1.6 Rotation–orbit resonance
2 Occurrence
2.1 Moons
2.1.1 The Moon
2.2 Planets
2.3 Stars
3 Timescale
4 List of known tidally locked bodies
4.1 Solar System
4.2 Extra-solar
5 Bodies likely to be locked
5.1 Solar System
5.2 Extrasolar
6 See also
7 References
Mechanism[edit]
The change in rotation rate necessary to tidally lock a body B to a larger body A is caused by the torque applied by A's gravity on bulges it has induced on B by tidal forces.
Tidal bulges[edit]
A's gravity produces a tidal force on B which distorts its
From Wikipedia, the free encyclopedia
Tidal locking results in the Moon rotating about its axis in about the same time it takes to orbit the Earth. Except forlibration effects, this results in the Moon keeping the same face turned towards the Earth, as seen in the figure on the left. (The Moon is shown in polar view, and is not drawn to scale.) If the Moon were not spinning at all, it would alternately show its near and far sides to the Earth while moving around our planet in orbit, as shown in the figure on the right.
Tidal locking (or captured rotation) occurs when the gravitational gradient makes one side of an astronomical body always face another, an effect known as synchronous rotation. For example, the same side of the Earth's Moon always faces the Earth. A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This causes one hemisphere constantly to face the partner body. Usually, at any given time only the satellite is tidally locked around the larger body, but if the difference in mass between the two bodies and their physical separation is small, each may be tidally locked to the other, as is the case between Pluto and Charon. This effect is employed to stabilize some artificial satellites.
Contents
[hide]
1 Mechanism
1.1 Tidal bulges
1.2 Bulge dragging
1.3 Resulting torque
1.4 Orbital changes
1.5 Locking of the larger body
1.6 Rotation–orbit resonance
2 Occurrence
2.1 Moons
2.1.1 The Moon
2.2 Planets
2.3 Stars
3 Timescale
4 List of known tidally locked bodies
4.1 Solar System
4.2 Extra-solar
5 Bodies likely to be locked
5.1 Solar System
5.2 Extrasolar
6 See also
7 References
Mechanism[edit]
The change in rotation rate necessary to tidally lock a body B to a larger body A is caused by the torque applied by A's gravity on bulges it has induced on B by tidal forces.
Tidal bulges[edit]
A's gravity produces a tidal force on B which distorts its