Nihal is the second brightest star of Lepus, lying close to Arneb near the centre of the constellation of the Hare that lies directly southward of Orion. Of the two stars, Nihal is much closer to the Solar System than Arneb (at a distance of some 160 light years, compared to Arneb's distance of about 2,200 light years). Arneb, however, is an intensely luminous supergiant, and so despite the stars' relative distances, it still appears rather brighter than Nihal in the sky.
To the Arabic astronomers who named this star, Nihal represented one of four cosmic camels in the act of drinking (the other three camels were represented by Arneb, together with Gamma and Delta Leporis to the southeast. From this association, Nihal gained its name, which originally applied to all four stars, and translates as something like 'quenching their thirst'.
Nihal is a chemically complex star, showing various unusual elements, and the fact that it is an X-ray source shows that the star is also magnetically active. Nihal is at a transitional point in its evolution, moving from the fusion of hydrogen in its core to a phase of fusing helium to form carbon. So the star is developing through a bright giant phase - making it currently more than 150 times as luminous as the Sun - toward becoming a true giant star.
This is a double star, with a faint variable companion lying less than three arcseconds away from the primary bright giant, although whether Nihal is a true binary, or merely a close optical double, has yet to be established with certainty.
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