R Sculptoris
R Sculptoris is a variable star system in the southern constellation of Sculptor. Parallax measurements provide a distance estimate of approximately from the Sun. An independent estimate based on measurements of an ejected shell surrounding the star yield a distance of. The star is drifting closer with a radial velocity of −5.4 km/s.
Benjamin Apthorp Gould discovered that the star's brightness varies, in 1872. It was listed with its variable star designation, R Sculptoris, in Annie Jump Cannon's 1907 work Second Catalog of Variable Stars. Both AAVSO and ASAS data shows that R Sculptoris is occasionally brighter than 6th magnitude, and faintly visible to the naked eye under excellent observing conditions.
File:RSclLightCurve.png|thumb|left|A visual band light curve for R Sculptoris, plotted from ASAS data
This is an aging giant star on the asymptotic giant branch with a stellar classification of C6,5ea, which indicates a carbon-rich atmosphere. It is a semi-regular pulsating star of the SRb type that is nearing the end of its fusing lifespan. A sine curve fitted to the last ten pulsation cycles prior to 2017 give a pulsation period of 376 days with an amplitude of 0.75 magnitude. The star is shedding its outer atmosphere, and it is surrounded by a thin shell of dust and gas that was created during the most recent thermal pulse around 2,000 years ago.
Observations have revealed a spiral structure in the material around the star. The spiral is suspected to be caused by an unseen companion star. The spiral windings are consistent with an orbital period of ~350 years.