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Proper NameLambda Orionis Cluster
Messier NumberNone
NGC/IC NumberNone
Other DesignationsCollinder 69
Right Ascension5h 35m 10s
Declination+9° 48' 47"
Distancec.1,300 light years
c.400 parsecs
MagnitudeApparent: +2.79
Absolute: -5.22
DiameterApparent: 1° 70'
Actual: 27 light years
Number of Starsc. 1,100
Optimum VisibilityDecember / January
NotesA young cluster of more than a thousand blue-coloured stars at a distance of some 1,300 light years from the Sun. The Lambda Orionis Cluster marks the 'head' of Orion, lying northwestward of Betelgeuse and northeastward of Bellatrix as seen from Earth (though in fact it lies far beyond these two prominent stars).

The brightest star in this image (immediately to the north of the reticle) is Meissa or Lambda Orionis, from which the cluster takes its common name. The bright star southward of Meissa is Phi1 Orionis, which is also a member, but orange Phi2 Orionis to the southeast is a foreground star, unrelated to the blue stars that make up the cluster. Imagery provided by Aladin sky atlas

The stars that form Orion's 'head' are part of an open star cluster identified as the Lambda Orionis Cluster, Collinder 69. The brightest of these is Meissa (also known as Heka), but the cluster contains numerous other stars in addition. The cluster seems to be relatively young, in astronomical terms, and probably formed no more than ten million years ago. Remnants of the nebulous material from which it formed can still be seen between the cluster's stars.


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