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Alrakis, Errakis, Mu Draconis, 21 Draconis

Proper NamesArrakis, Alrakis, Errakis
Bayer DesignationMu Draconis
Flamsteed Number21 Draconis
Right Ascension17h 05m 20s
Declination+54° 28' 12"
Distance88 light years
27 parsecs
MagnitudeApparent: +4.9
Absolute: +2.8
Spectral ClassF7 Bright Yellow Dwarf
Optimum VisibilityMay/June
NotesThe heart of the Arrakis system consists of two yellow-white stars orbiting one another at a distance of about 90 AU, a mutual orbit that take nearly seven centuries to complete.
Image of Arrakis

The view from a hypothetical planet in the Arrakis system. Bright in the sky are the twin stars that make up the core of the system. The third and more distant component, Arrakis C, shines like a 'morning star'.

The name Arrakis comes from Arabic, and means 'The Dancer'. This is indeed an appropriate name for a three-star system, where the two major components are almost identical stars rotating around their common centre of gravity. A third, fainter, star pursues a more distant orbit around these two.


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