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Proper NameNone
Bayer DesignationNone
Flamsteed Number55 Orionis
HR (BSC)2031
Right Ascension5h 51m 22s
Declination-7° 31' 5"
Distance994 light years
305 parsecs
MagnitudeApparent: +5.3
Absolute: -2.2
Spectral ClassB2IV Blue Subgiant
Optimum VisibilityDecember / January
Notes55 Orionis is a distant star in the southeastern parts of Orion, near that constellation's border with Monoceros. Much hotter and more luminous than the Sun, the significant distance of this star - just under 1,000 light years - means that it is nonetheless on the threshold of naked-eye visibility.

The distinctive object to the east of 55 Orionis here is not a star, but the distant elliptical galaxy NGC 2110. The faint nebulosity visible in the background of this image is part of the southeastern arc of Barnard's Loop, a vast structure centred on the nebulae of the Sword of Orion (the shape of the Loop can be seen more clearly by zooming out from 55 Orionis). Imagery provided by Aladin sky atlas


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