Wikipedia:Today's featured article/June 4, 2016
Circinus is a small, faint constellation in the southern sky, first defined in 1756 by French astronomer Nicolas Louis de Lacaille. Its name is Latin for compass, a tool that draws circles. Its brightest star is the slightly variable Alpha Circini, the brightest rapidly oscillating Ap star in the night sky, with an apparent magnitude of 3.19. AX Circini is a Cepheid variable visible with the unaided eye, and BX Circini is a faint star thought to have been formed from two merged white dwarfs. The sun-like star HD 134060 has two small planets, and another, HD 129445, has a Jupiter-like planet. Supernova SN 185 appeared in Circinus in 185 AD and was recorded by Chinese observers. Two novae were observed in the 20th century. The Milky Way runs through the constellation, featuring prominent objects such as the open cluster NGC 5823 and the planetary nebula NGC 5315 (pictured). The Circinus Galaxy, discovered in 1977, is the closest Seyfert galaxy to the Milky Way. The Alpha Circinid meteor showers, discovered the same year, radiate from this constellation. (Full article...)