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Hamal (Alpha Arietis)

Hamal and the constellation aries
Hamal (Alpha Arietis) is easily the brightest star in the constellation Aries, an orange giant K star. Its Arabic name, meaning "the lamb," stands for the whole constellation of the Ram. Hamal had the distinction, at least up until a few years ago, of having, along with Shedar (Alpha Cassiopeiae), the most accurately-measured angular diameter – 0.00680" (the width of a cent coin seen from 60 km away). This precise measurement also enabled Hamal to become one of the few stars for which limb darkening has been detected.

visual magnitude 2.01
absolute magnitude 0.48
spectral type K2III
surface temperature 4,590 K
luminosity 90 Lsun
radius 15 Rsun
mass 2 Msun
distance 66 light-years
position R.A. 02h 07m 10.4s,
Dec. +23 27' 45"

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