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Thus, Philippe Loys de Chéseaux independently rediscovered it in 1745-46, and was the first to recognize it as "a very fine star cluster." Abbe Lacaille included it in his catalog of 1751-52 as Lac III.12, and Charles Messier eventually cataloged it on May 23, 1764.
The distance of M6 was estimated by Rohlfs et.al.
Of all Messier objects, M6 is situated at the closest angular distance from the Galactic Center, which is located in the constellation Sagittarius but very near to the 3-constellation edge of Sagittarius, Scorpius and Ophiuchus.