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Open cluster

An open cluster is a type of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. Each one is loosely bound by mutual gravitational attraction and becomes…

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Density
~ 1.5 stars / cubic ly
Size range
< 30 ly in diameter
Type
Loose cluster of stars

Topics to explore

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Overview

Historical observations

Formation

Morphology and classification

Numbers and distribution

Stellar composition

Eventual fate

Studying stellar evolution

Astronomical distance scale

Planets

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Map overview Semantic statistics

Open cluster

Nodes150
Edges149
Triples125
Avg. degree1.99
Density0.013333
Components1

How this topic connects Entity context

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Open cluster

Top relations

related to Historical observations · 32
Open cluster → Al-Sufi, Almagest, Coma Star Cluster, Double Cluster, For Praesepe, Galileo Galilei, Galileo's, Giovanni Hodierna, However, Hyades, In, Indeed, Influenced, Italian, Johann Bayer, Messier, NGC, Omicron Velorum, Other, Perseus
related to Morphology and classification · 12
Open cluster → An, Arabic, For, I-IV, Open, Robert Trumpler, Roman, Sun, The, The Trumpler, They, Typical
related to Astronomical distance scale · 11
Open cluster → Calibration, Clusters, Determining, Earth, First, Hipparcos, Hyades, Open, Pleiades, Sun, The
related to External links · 11
Open cluster → Archived, Clusters, Crux, Information, Kappa Crucis Cluster, NGC, ORGOpen Star Clusters, SEDS Messier, SKY-MAP, The Jewel Box, Wayback Machine
related to Formation · 10
Open cluster → Even, In, Many, Milky Way, Prior, Sun, The, These, This, Typically
related to Planets · 8
Open cluster → Additionally, Beehive Cluster, For, Jupiters, Kepler-66, Kepler-67, NGC, The
related to Studying stellar evolution · 7
Open cluster → Because, Earth, Hertzsprung, Russell, The, This, When
related to Eventual fate · 6
Open cluster → Clusters, In, Internally, Many, These, This
related to Numbers and distribution · 4
Open cluster → In, Open, Star, There
related to Stellar composition · 4
Open cluster → Because, The, These, This

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Important terminology

clusters stars cluster open star many cloud pleiades years members formation stellar galaxy known gas distance form hyades one found

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Open clusterDensity~ 1.5 stars / cubic ly1.00infobox
Open clusterSize range< 30 ly in diameter1.00infobox
Open clusterTypeLoose cluster of stars1.00infobox
Open clusteris atype of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age0.90text
Open clusteris aHyades0.90text
the Pleiades does forminstance ofEven when a cluster0.80text
it may hold on to only a third of the original starsinstance ofEven when a cluster0.80text
with the remainder becoming unbound once the gas is expelledinstance ofEven when a cluster0.80text
Palomar 12instance ofthere may not be a great deal of intrinsic difference between a very sparse globular cluster0.80text
a very rich open clusterinstance ofthere may not be a great deal of intrinsic difference between a very sparse globular cluster0.80text
passing close to or through a molecular cloudinstance ofabout every half-billion years or so an open cluster tends to be disturbed by external factors0.80text
ageinstance ofvariables0.80text

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