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IC 4665

Proper NameNone
Messier NumberNone
NGC/IC NumberIC 4665
ConstellationOphiuchus
Right Ascension17h 46m 18s
Declination+5° 43' 0"
Distancec.1,100 light years
c.300 parsecs
MagnitudeApparent: +4.2
Absolute: -3.5
DiameterApparent: 70'
Actual: 23 light years
Number of Starsc. 30
Optimum VisibilityJune / July
NotesIC 4665 is a widely scattered open cluster covering an area of the sky comparable to that of the Moon's disc. The cluster as a whole approaches magnitude +4.2, and is visible to the naked eye under ideal conditions. Its individual stars are fainter, with none exceeding magnitude +6.8, and so optical aid is required to see details of the cluster's structure.
Relative Galactic Position of IC 4665

IC 4665 is an open cluster in the constellation of the Serpent Holder. From Earth, it appears to lie in the approximate direction of our Galaxy's Nuclear regions.

IC 4665 is a cluster of about thirty stars that began to develop less than forty million years ago, lying about 1,400 light years from Earth in the constellation of Ophiuchus. By comparison with most star clusters, these figures make it very young and - relatively speaking - nearby. The cluster is just visible to the naked eye, as a faint point of light somewhat to the south of Rasalhague.

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