moving cluster

astronomy

Also known as: moving group

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July 1, 2026

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A moving cluster in astronomy is a group of stars that share common motions through space. These clusters are typically open clusters located relatively near the Sun, allowing for the measurement of their individual proper motions.1

A prominent example of a moving cluster is the Hyades, located in the constellation Taurus. The stars within a moving cluster are actually moving as a swarm in nearly parallel directions and at similar speeds. The apparent convergence of their proper motions towards a single point in the sky is due to perspective. The Ursa Major group is another example of a moving cluster, though the Sun is not a member despite being within its volume of space.23

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star cluster
Open clusters
…few clusters are known as moving clusters because the convergence of the proper motions of their individual stars toward a “convergent point” is pronounced. The apparent convergence is caused by perspective: the cluster members are really moving as a swarm in almost parallel directions and with about the same speeds.…
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…few clusters are known as moving clusters because the convergence of the proper motions of their individual stars toward a “convergent point” is pronounced. The apparent convergence is caused by perspective: the cluster members are really moving as a swarm in almost parallel directions and with about the same speeds.…
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Milky Way Galaxy
Moving groups
These objects are organizations of stars that share common measurable motions. Sometimes these do not form a noticeable cluster. This definition allows the term to be applied to a range of objects from the nearest gravitationally bound clusters to groups of widely spread…
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These objects are organizations of stars that share common measurable motions. Sometimes these do not form a noticeable cluster. This definition allows the term to be applied to a range of objects from the nearest gravitationally bound clusters to groups of widely spread…
Read More