Sigma Sagittarii

Common card · No. 429547

Sigma Sagittarii, Latinized from σ Sagittarii; formally named Nunki , is the second-brightest star in the constellation of Sagittarius. It is a binary star system, viewed as a single star of combined apparent magnitude +2.05, about the same brightness as Saiph in Orion. The distance to this system, determined using a dynamical parallax measurement, is 225 light-years (68.9 parsecs). It is 3.45 degrees south of the ecliptic, so it can be occulted by the Moon and rarely by planets. The last occultation by a planet took place on November 17, 1981, when it was occulted by Venus.

Read on Wikipedia · Image IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg), CC BY 3.0