Editing Beehive Cluster (section)

== Morphology and composition ==
Like many [[star cluster]]s of all kinds, Praesepe has experienced [[mass segregation]].<ref name="Kraus2007"/><ref name="Adams2002"/><ref name="Portegies2001">
{{cite journal
 |author=Portegies Zwart SF
 |author2=McMillan SL
 |author3=Hut P
 |author4=Makino J
 |date=2001
 |title=Star cluster ecology IV. Dissection of an open star cluster: Photometry
 |journal=[[Monthly Notices of the Royal Astronomical Society]]
 |volume=321 |issue=2
 |pages=199–226
 |bibcode= 2001MNRAS.321..199P
 |doi=10.1046/j.1365-8711.2001.03976.x
|doi-access=free
 |arxiv = astro-ph/0005248 |s2cid=18396503
 }}</ref> This means that bright massive stars are concentrated in the cluster's core, while dimmer and less massive stars populate its halo (sometimes called the ''corona''). The cluster's core radius is estimated at 3.5 parsecs (11.4 light years); its half-mass radius is about 3.9 parsecs (12.7 light years); and its  [[Roche limit|tidal radius]] is about 12 parsecs (39 light years).<ref name="Kraus2007"/><ref name="Adams2002"/> However, the tidal radius also includes many stars that are merely "passing through" and not ''bona fide'' cluster members.
[[File:M44 47x300s-10°C O30 G0 PM RGB 03032022.jpg|thumb|The Beehive Cluster in Cancer]]

Altogether, the cluster contains at least 1000 gravitationally bound stars, for a total mass of about 500–600 Solar masses.<ref name="Kraus2007" /><ref name="Adams2002" /> A recent survey counts 1010 high-probability members, of which 68% are [[red dwarf|M dwarfs]], 30% are Sun-like stars of [[stellar classification|spectral classes]] F, G, and K, and about 2% are bright stars of spectral class A.<ref name="Kraus2007" /> Also present are five giant stars, four of which have spectral class K0 III and the fifth G0 III.<ref name="Klein-Wassink1927" /><ref name="Kraus2007" /><ref name="Abt1999">
{{cite journal
 |author=Abt HA |author2=Willmarth DW
 |date=1999
 |title=Binaries in the Praesepe and Coma star clusters and their implications for binary evolution
 |journal=[[Astrophysical Journal]]
 |volume=521 |issue=2
 |pages=682–690
 |bibcode=1999ApJ...521..682A
 |doi=10.1086/307569
|s2cid=119772785
 |doi-access=free
 }}</ref>

So far, eleven [[white dwarf]]s have been identified, representing the final evolutionary phase of the cluster's most massive stars, which originally belonged to spectral type B.<ref name="Dobbie2006"/> [[Brown dwarf]]s, however, are rare in this cluster,<ref name="Gonzalez-Garcia2006"/> probably because they have been lost by tidal stripping from the halo.<ref name="Kraus2007"/> A brown dwarf has been found in the [[eclipsing binary]] system AD 3116.<ref name="Gillen2018"/>

The cluster has a visual brightness of magnitude 3.7. Its brightest stars are blue-white and of magnitude 6 to 6.5. [[42 Cancri]] is a confirmed member.