Beta Boötis Beta Boötis Beta Boötis (β Boötis, abbreviated Beta Boo, β Boo), also named Nekkar, is a star in the northern constellation of Boötes. It has an apparent visual magnitude of 3.5, making it one of the brighter members of the constellation. In the modern constellation, it marks the head of Boötis the herdsman. Based upon parallax measurements obtained during the Hipparcos mission, this star is approximately from the Sun. At that distance, the magnitude of the star is reduced by 0.06 from extinction caused by intervening gas and dust. "β Boötis" (Latinised to "Beta Boötis") is the star's Bayer designation.
Cancer (constellation) as a lobster. Richard Allen, in "Star-names and Their Meanings", lists names for the constellation as follows: In Ancient Greece, Aratus called the crab "Καρκινος" ("Karkinos"), which was followed by Hipparchus and Ptolemy. The Alfonsine tables called it "Carcinus", a Latinized form of the Greek word. Eratosthenes extended this as "Καρκινος", "Ονοι", "και Φατνη" ("Karkinos", "Onoi", "kai Fatne"): the Crab, Asses, and Crib. In Ancient Rome, Manilius and Ovid called the constellation "Litoreus" (shore-inhabiting). "Astacus" and "Cammarus" appear in various classic writers, while it is called "Nepa" in Cicero's "De Finibus" and the works of Columella, Plautus, and Varro; all