Wikipedia:Today's featured article/April 23, 2015

Caelum is a faint constellation in the southern sky, introduced in the 1750s by Nicolas Louis de Lacaille. Latin for "chisel", it is the eighth-smallest constellation, measuring around 0.038 steradians, just smaller than Corona Australis. Caelum is a rather barren constellation with few objects of interest, due to its small size and location away from the plane of the Milky Way. The constellation's brightest star, Alpha Caeli, is only of magnitude 4.45, and only one other star (Gamma¹ Caeli) is brighter than magnitude 5. Other notable objects in Caelum are RR Caeli, a binary star with one planet approximately 20.13 parsecs (65.7 ly) away; X Caeli, a Delta Scuti variable that forms an optical double with Gamma¹ Caeli; and HE0450-2958, a Seyfert galaxy (pictured) that at first appeared as just a jet, with no host galaxy visible. The source of the jet was once suggested to be a supermassive black hole, but is now agreed to be a small galaxy that is partially obscured by light from the jet and a nearby starburst galaxy. (Full article...)

Recently featured: SM U-66 – Seated Liberty dollar – Rhodotus