S Doradus is one of the brightest stars in the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way, located roughly 160,000 light-years away. The star is a luminous blue variable, and one of the most luminous stars known, having a luminosity varying widely above and below 1,000,000 times the luminosity of the Sun, although it is too far away to be seen with the naked eye.
Rho Cassiopeiae is a yellow hypergiant star in the constellation Cassiopeia. It is about 3,400 light-years (1,000 pc) from Earth, yet can still be seen by the naked eye as it is over 300,000 times brighter than the Sun. On average it has an absolute magnitude of −9.5, making it visually one of the most luminous stars known. Its diameter measures between 400 and 500 times that of the Sun, approximately 627,000,000 kilometers, or about twice the size of the Earth's orbit.
T Coronae Borealis, is a recurring nova in the constellation Corona Borealis. It was first discovered in outburst in 1866 by John Birmingham, although it had been observed earlier as a 10th magnitude star.
13 Andromedae, abbreviated 13 And, is a single, blue-white hued variable star in the northern constellation of Andromeda. 13 Andromedae is the Flamsteed designation, while it bears the variable star designation V388 Andromedae. With a typical apparent visual magnitude of around 5.75, it is dimly visible to the naked eye under good seeing conditions. The distance to this star can be directly estimated from its annual parallax shift of 10.9 mas, yielding a range of 300 light years. At that distance, its brightness is diminished by an extinction of 0.13 magnitude due to interstellar dust. The star is moving closer to the Earth with a heliocentric radial velocity of −8 km/s.
Z Andromedae is a binary star system consisting of a red giant and a white dwarf. It is the prototype of a type of cataclysmic variable star known as symbiotic variable stars or simply Z Andromedae variables. The brightness of those stars vary over time, showing a quiescent, more stable phase and then an active one with a more pronounced variability and stronger brightening and/or dimming.
EQ Virginis is a single variable star in the equatorial constellation of Virgo. It has a baseline visual apparent magnitude of 9.36, but is a flare star that undergoes sporadic bursts of brightening. The star is located at a distance of 67 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −23 km/s. It is a member of the IC 2391 moving group of stars, which is between 30 and 50 million years old.
HR Carinae is a luminous blue variable star located in the constellation Carina. It is surrounded by a vast nebula of ejected nuclear-processed material because this star has a multiple shell expanding atmosphere. This star is among the most luminous stars in the Milky Way. It has very broad emission wings on the Balmer lines, reminiscent from the broad lines observed in the spectra of O and Wolf–Rayet stars. A distance of 5 kpc and a bolometric magnitude of -9.4 put HR Car among the most luminous stars of the galaxy.
BK Camelopardalis is a variable star in the northern circumpolar constellation of Camelopardalis, near the constellation border with Cassiopeia. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude that fluctuates around 4.74. The star is located approximately 540 light years away from the Sun based on parallax. It is a proposed member of the Cassiopeia–Taurus group of co-moving stars.
V518 Carinae is a naked-eye variable star in the constellation Carina. It is a member of the bright open cluster IC 2602 near the Carina Nebula.
CL Draconis is a single star in the northern circumpolar constellation of Draco. It can be viewed with the naked eye, having an apparent visual magnitude of 4.96. The distance to this star, as determined from its annual parallax shift of 29.9 mas, is 109 light years. It is moving closer to the Earth with a heliocentric radial velocity of −11 km/s. The star has a relatively high proper motion, traversing the celestial sphere at the rate of 0.185″/yr.
AG Pegasi is a symbiotic binary star in the constellation Pegasus. It is a close binary composed of a red giant and white dwarf, estimated to be around 2.5 and 0.6 times the mass of the Sun respectively. It is classified as a symbiotic nova; it has undergone one extremely slow nova outburst and a smaller outburst.
SU Ursae Majoris, or SU UMa, is a close binary star in the northern circumpolar constellation of Ursa Major. It is a periodic cataclysmic variable that varies in magnitude from a peak of 10.8 down to a base of 14.96. The distance to this system, as determined from its annual parallax shift of 4.53 mas, is 719 light-years. It is moving further from the Earth with a heliocentric radial velocity of +27 km/s.
AO Mensae is a single variable star in the southern circumpolar constellation of Mensa. It is too faint to be viewed with the naked eye, having an apparent visual magnitude that ranges from 9.96 down to 10.18. The star is 128 light years distant from the Sun based on parallax, and is drifting further away with a radial velocity of +16 km/s. It is a member of the Beta Pictoris moving group, a loose association of young stars moving through the galaxy.
CH Cygni is a red giant, variable, symbiotic binary in the constellation Cygnus. It is the nearest symbiotic star to Earth, and one of the brightest, making it an ideal candidate for study.
EX Lupi is a young, single T-Tauri star in the southern constellation of Lupus. An irregular variable, it is the prototype of young, low-mass eruptive stars named EXors, with EX Lupi being this object's variable star designation. At its minimal activity level, EX Lupi resembles a classical T-Tauri star of the M0 dwarf type. The low latitude of this star, at a declination of −40°, makes it difficult for northern observers to view. Based on parallax measurements, it is located at a distance of approximately 514 light years from the Sun. The star lies next to a gap in the Lupus cloud complex, a star forming region.
HM Sagittae is a dusty-type symbiotic nova in the northern constellation of Sagitta. It was discovered by O. D. Dokuchaeva and colleagues in 1975 when it increased in brightness by six magnitudes. The object displays an emission line spectrum similar to a planetary nebula and was detected in the radio band in 1977. Unlike a classical nova, the optical brightness of this system did not rapidly decrease with time, although it showed some variation. It displays activity in every band of the electromagnetic spectrum from X-ray to radio.
V1005 Orionis is a young flare star in the equatorial constellation of Orion. It has the identifier GJ 182 in the Gliese–Jahreiß catalogue; V1005 Ori is its variable star designation. This star is too faint to be visible to the naked eye, having a mean apparent visual magnitude of 10.1. It is located at a distance of 79.6 light years from the Sun and is drifting further away with a radial velocity of 19.2 km/s. The star is a possible member of the IC 2391 supercluster.
RW Tauri is a binary star system in the equatorial constellation of Taurus. It has the designation HD 25487 in the Henry Draper Catalogue, while RW Tauri is the variable star designation. With a peak apparent visual magnitude of 8.05, it is too faint to be visible to the naked eye. The distance to this system is approximately 940 light years based on parallax measurements.
PU Vulpeculae is a very slowly evolving symbiotic nova in the northern constellation of Vulpecula, abbreviated PU Vul. It is too faint to be visible to the naked eye, reaching a maximum apparent visual magnitude of 8.7 following a minimum of 16.6. The system is located at a distance of approximately 17,000 light years from the Sun based on parallax measurements.
X Cygni is a variable star in the northern constellation of Cygnus, abbreviated X Cyg. This is a Delta Cephei variable that ranges in brightness from an apparent visual magnitude of 5.85 down to 6.91 with a period of 16.386332 days. At it brightest, this star is dimly visible to the naked eye. The distance to this star is approximately 628 light years based on parallax measurements. It is drifting further away with a radial velocity of 8.1 km/s. This star is a likely member of the open cluster Ruprecht 173.
