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Directly southward of the head and forepaws of Leo the Lion and the bright star Regulus lies a patch of sky, devoid of bright stars, designated Sextans the Sextant. Alpha Sextantis is the brightest star in this region, but nonetheless with an apparent magnitude of just +4.48 it is only barely visible to the naked eye.

Imagery provided by Aladin sky atlas

Alpha Sextantis is a white star a little under 430 light years from the Sun (many reference sources place it at a distance of about 280 light years, but the recent Gaia measurements suggest that it is considerably farther than this to the Solar System). This is a giant star, some three times the Sun's diameter, that is in the process of evolving from a white giant to an orange giant as its hydrogen reserves are depleted.

On the Celestial Sphere, Alpha Sextantis lies very close to the Equator, and in fact it crossed the Equator from the northern to the southern hemisphere in the year 1923. Less than two degrees from the star in the sky lies the Sextans Dwarf Galaxy, a small satellite galaxy of the Milky Way that lies far, far beyond the star Alpha Sextantis at a distance of some 300,000 light years.


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