Local objects are commonly examined as to their vectors of position angle and radial velocity.
These can be combined through vector addition to state the object's motion relative to the Sun.
Galaxies are not distributed evenly throughout observable space, but are typically found in groups or clusters, where they have a significant gravitational effect one on another.
Velocity dispersions of galaxies arising from this gravitational attraction are usually in the hundreds of kilometers per second, but they can rise to over 1000 km/s in rich clusters.
[5] The main consequence is that, in determining the distance of a single galaxy, a possible error must be assumed.
For example, in surveys of type Ia supernovae, peculiar velocities have a significant influence on measurements out to redshifts around 0.5, leading to errors of several percent when calculating cosmological parameters.
Current analysis of experimental bulk flow values are not in good agreement with the Lambda-CDM model.