Orion's Belt!
Although strictly speaking, "Orion's Belt" is an asterism rather than a constellation.
Aldebaran is the brightest star in the constellation of the Gemini
The star Regulus, or Alpha Leonis, can be found in the constellation of Leo. It is the brightest star in the constellation.
Polaris, aka the pole star or the north star, is in the constellation of Ursa Minor.
The 15th star in a constellation group will vary depending on which constellation you are referring to, as each constellation has a different number of stars. It would be helpful to specify the constellation in order to determine the 15th star.
Polaris is in the constellation of Ursa Minor.
The star Achernar is the brightest star in the constellation EridanusThere is no star called chernar. The star Achernar is the brightest star in the constellation Eridanus.
a constellation is a group of stars and a star is one star
The star Aldebaran is the "eye" of Taurus, the Bull.
Regulus (α Leo / α Leonis / Alpha Leonis) is the brightest star in the constellation Leo and one of the brightest stars in the nighttime sky.
little dipper (constellation)Lacerta (constellation)Leo (constellation)Leo Minor (constellation)Lepus (constellation)Libra (constellation)Lupus (constellation)Lynx (constellation)Lyra (constellation)Lanx Australis (star)La Superba (star)Lesath (star)Lucida Anseris (star)
The star constellation for December is Sagittarius.
The Rigel star is a star in the Orion constellation. Rigel is the brightest star in the Orion constellation, and it is the seventh brightest star seen in the night's sky.