Sidus Ludoviciana
Sidus Ludoviciana is an 8th-magnitude giant star in the asterism of the Big Dipper in the constellation Ursa Major, halfway between Mizar and Alcor. It was discovered on 2 December 1722 by Johann Georg Liebknecht, who mistook it for a planet and named it after Louis V, Landgrave of Hesse-Darmstadt. A line-of-sight companion with Mizar and Alcor, it is roughly four times more distant. It has the spectral type A8/F0 III.
The star is six times more luminous than the Sun, 1.6 times its radius, and has an surface temperature of. It has exhausted its core hydrogen and evolved away from the main sequence.
