Omicron Serpentis is a solitary star in the Serpens Cauda (tail) section of the equatorial constellation Serpens. Based upon an annual parallax shift of 18.83 mas as seen from Earth, it is located around 173 light years from the Sun. The star is visible to the naked eye with a base apparent visual magnitude of +4.26.
Kappa Trianguli Australis is a star in the constellation Triangulum Australe.
R Horologii is a red giant star approximately 760 light-years away in the southern constellation of Horologium. It is a Mira variable with a period of 404.83 days, ranging from apparent magnitude 4.7 to 14.3—one of the largest ranges in brightness known of stars in the night sky visible to the unaided eye. The star is losing mass at the rate of 5.9×10−7 M☉·y−1.
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.
R Cassiopeiae is a variable star in the northern constellation of Cassiopeia. It is located approximately 574 light years distant from the Sun, but is drifting closer with a radial velocity of −23 km/s. This is a pulsating Mira-type variable star with a brightness varies from magnitude +4.4 down to +13.5 with a period of 433.6 days. At its maximum, R Cassiopeiae is visible to the naked eye as a faint, red-hued star.
R Centauri is a Mira variable star in the constellation Centaurus.
R Aquilae is a variable star in the equatorial constellation of Aquila. It is located approximately 760 light years distant from the Sun and is drifting further away with a radial velocity of 35 km/s. This is a thermally-pulsating Mira variable that ranges in brightness from 5.3 down to 12.0 with a period of 269.84 days. The period was over 300 days when first observed, and has declined steadily since – decreasing from 320 in 1915 down to 264 in 2010, at an average rate of 0.4 days per year. The amplitude of the variation has also decreased by about a magnitude since discovery. The peak magnitude is bright enough for the star to be visible to the naked eye as a dim, red-hued star.
R Reticuli, also listed under the duplicate variable star designation S Reticuli, is a Mira variable star in the southern constellation Reticulum. It is an aging red giant star on the asymptotic giant branch with a stellar classification that varies between M4e to M7.5e, being hottest near maximum visual magnitude. The brightness of the star varies between apparent visual magnitudes 6.35 and 14.2 with an average period of 281.08±0.58 d. The mean maximum magnitude is 7.57 and the mean minimum magnitude 13.80.
HD 14622 is a single star in the northern constellation of Andromeda. It is dimly visible to the naked eye under good seeing conditions, having an apparent visual magnitude of 5.81. Based upon an annual parallax shift of 20.9 mas, it is located 156 light years away. The star is moving closer to the Earth with a heliocentric radial velocity of −35 km/s, and is predicted to come within 96 light-years in around 812,000 years.
R Boötis is a variable star in the northern constellation of Boötes. Typically the star is too faint to be readily visible to the naked eye, with a brightness that fluctuates between apparent visual magnitudes of 9.98. The distance to this star is approximately 2,150 light years based on parallax measurements. It is drifting closer with a radial velocity of about −58 km/s.
W Andromedae is a variable star in the constellation of Andromeda. It is classified as a Mira variable and S-type star, and varies from an apparent visual magnitude of 14.6 at minimum brightness to a magnitude of 6.7 at maximum brightness, with a period of approximately 397.3 days. The star is losing mass due to stellar winds at a rate of 2.79×10−7M☉/yr.
Zeta Chamaeleontis, Latinized from ζ Chamaeleontis, is a star located in the constellation Chamaeleon. Located around 540 light-years distant, it shines with a luminosity approximately 522 times that of the Sun and has a surface temperature of 15,655 K.
S Canis Minoris is a variable star in the equatorial constellation Canis Minor. It has a peak apparent visual magnitude of 6.5, so not normally visible to the naked eye. The star is located at a distance of approximately 1,530 light-years from the Sun based on stellar parallax, and is drifting further away with a radial velocity of about +68 km/s.
R Geminorum is a Mira variable and technetium star in the constellation Gemini. It is located approximately 850 parsecs (2,800 ly) away.
S Boötis is a Mira variable in the constellation Boötes. It ranges between magnitudes 7.8 and 13.8 over a period of approximately 270 days. It is too faint to be seen with the naked eye, however when it is near maximum brightness it can be seen with binoculars.
U Microscopii is a Mira variable star in the constellation Microscopium. It ranges from magnitude 7 to 14.4 over a period of 334 days. The Astronomical Society of Southern Africa in 2003 reported that observations of U Microscopii were very urgently needed as data on its light curve was incomplete.
DU Lyncis is a single variable star in the constellation Lynx. It is a faint star but visible to the naked eye with an apparent visual magnitude of 5.15. With an annual parallax shift of 9.2 mas, it is located some 350 light years from the Sun. The star is moving closer with a heliocentric radial velocity of −37 km/s.
R Octantis, also known as HD 40857, is a solitary, red hued variable star located in the southern circumpolar constellation Octans. It has an apparent magnitude that varies in-between 6.4 and 13.2 within 405 days. At is maximum, it is barely visible to the naked eye. The object is located relatively far at a distance of about 1,900 light years based on parallax measurements from Gaia DR3, but is receding with a heliocentric radial velocity of 46 km/s.
T Leporis is a variable star in the constellation of Lepus, the Hare. It is located half a degree from ε Leporis in the sky; its distance is approximately 1,100 light years from the Solar System. It has the spectral type M6ev, and is a Mira variable — as is R Leporis, in the same constellation — whose apparent magnitude varies between +7.40 and +14.30 with a period of 368.13 days.
V Crucis is a carbon star in the constellation Crux. A Mira variable, its apparent magnitude ranges from 8.7 to 11.1 over 376.5 days. The fact that this star's period is nearly equal to one year makes it hard to get good observational coverage over the entire cycle. Its near-infrared light curve shows a contribution from the first harmonic of the fundamental period.
