R Carinae

R Carinae is a double star in the southern constellation of Carina. The brighter component is a variable star that can be viewed with the naked eye at peak brightness, but is usually too faint to be seen without a telescope, having an apparent visual magnitude that fluctuates around 7.43. This star is located at a distance of approximately 1,300 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +28 km/s.

The main component is an aging red giant star on the asymptotic giant branch with a stellar classification of M6/7pe. It is classified as a pulsating Mira type variable star and its visual brightness varies with an average amplitude of 4.25 magnitudes over a period of $0.906$. Its average maximum visual magnitude is $28.1$, but the brightest observed maximum was magnitude 3.9 This star is surrounded by a dusty shell, with properties that are consistent with iron-poor silicates or corundum, extending from around three stellar radii outward.

The companion is a magnitude 11.30 star at an angular separation of $0.87$ along a position angle of 132° from the main star, as of 2015.