V1974 Cygni or Nova Cygni 1992 was a nova, visible to the naked eye, in the constellation Cygnus. It was discovered visually with 10×50 binoculars on February 19, 1992, by Peter Collins, an amateur astronomer living in Boulder, Colorado. At that time he first noticed it, it had an apparent magnitude of 7.2. Nine hours later he saw it again, and it had brightened by a full magnitude. For this discovery Collins was awarded the AAVSO Nova Award in 1993. The nova reached magnitude 4.4 at 22:00 UT on 22 February 1992. Images from the Palomar Sky Survey taken before the nova event showed identified a possible precursor which had photographic magnitudes of 18 and 17, but the identification of the precursor is not firm.
V1500 Cygni or Nova Cygni 1975 was a bright nova occurring in 1975 in the constellation Cygnus. It had the second highest intrinsic brightness of any nova of the 20th century, exceeded only by CP Puppis in 1942.
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.
DI Lacertae or Nova Lacertae 1910 was a nova in constellation Lacerta which appeared in 1910. It was discovered by Thomas Henry Espinell Compton Espin at Wolsingham Observatory on 30 Dec 1910, at which time it was an 8th magnitude object. Subsequent examination of pre-discovery photographic plates showed that the outburst occurred sometime between 17 November 1910 and 23 November 1910. It reached a peak brightness of magnitude 4.6 on 26 November 2021, making it visible to the naked eye. Before the nova event DI Lacertae was a 14th magnitude star, and by 1950 it had returned to 14th magnitude.
V1668 Cygni was a nova that appeared in the northern constellation of Cygnus, situated a couple of degrees to the southeast of the star Rho Cygni. It was discovered by Canadian variable star observer Warren Morrison on September 10, 1978, and reached a peak brightness of around 6.22 apparent magnitude on September 12. The luminosity of the source at this time was about 100,000 times the brightness of the Sun, and likely remained at that level for several months. The expansion velocity of the nova shell was deduced through spectroscopy to be 1,300 km/s.
U Geminorum, in the constellation Gemini, is an archetypal example of a dwarf nova. The binary star system consists of a white dwarf closely orbiting a red dwarf. Every few months it undergoes an outburst that greatly increases its brightness. The dwarf nova class of variable stars are often referred to as U Geminorum variables after this star.
SS Cygni is a variable star in the northern constellation Cygnus. It is the prototype of the subclass of dwarf novae that show only normal eruptions. It typically rises from 12th magnitude to 8th magnitude for 1–2 days every 7 or 8 weeks. The northerly declination of SS Cygni makes the star almost circumpolar from European and North American latitudes, allowing a large proportion of the world's amateur astronomers to monitor its behavior. Furthermore, since the star lies against the rich backdrop of the Milky Way band, the telescope field of view around SS Cygni contains an abundance of useful brightness comparison stars.
WR 134 is a variable Wolf-Rayet star located around 6,000 light years away from Earth in the constellation of Cygnus, surrounded by a faint bubble nebula blown by the intense radiation and fast wind from the star. It is five times the radius of the sun, but due to a temperature over 63,000 K it is 400,000 times as luminous as the Sun.
31 Cygni, also known as ο1 Cygni, Omicron1 Cygni, or V695 Cygni, is a star in the constellation Cygnus.
GQ Muscae, also known as Nova Muscae 1983 is a binary star system in the constellation Musca composed of a white dwarf and small star that is about 10% as massive as the Sun. The two orbit each other every 1.4 hours. The white dwarf accumulates material from its companion star on its accretion disc until it erupts, as it did in 1983, reaching a magnitude of 7.2. Discovered with a magnitude of 7.1 on 18 January 1983, it was the first nova from which X-rays were detected.
BC Cygni is a red supergiant and pulsating variable star of spectral type M3.5Ia in the constellation Cygnus.
RW Cygni is a semiregular variable star in the constellation Cygnus, about a degree east of 2nd magnitude γ Cygni. Its apparent magnitude varies between 8.05 and 9.70 and its spectral type between M3 and M4.
BV Centauri is a cataclysmic variable binary star in the constellation Centaurus. It is a dwarf nova, and undergoes rapid increases in brightness that are recurrent with a mean period of 150 days. This period seems to have increased in the last few decades. During quiescence, its visual apparent magnitude is about 13, with variations of a few tenths of magnitude over an orbit due to differences in the star's visible surface area, brightening to a maximum magnitude of 10.7 during outbursts. From its luminosity, it is estimated that the system is about 500 parsecs (1,600 ly) away from Earth. A Gaia parallax of 2.81 mas has been measured, corresponding to about 360 pc.
V392 Persei, also known as Nova Persei 2018, is a bright nova in the constellation Perseus discovered on April 29, 2018. It was previously known as a dwarf nova.
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.
AR Andromedae is a dwarf nova of the SS Cygni type in the constellation Andromeda. Its typical apparent visual magnitude is 17.6, but increases up to 11.0 magnitude during outbursts. The outbursts occur approximately every 23 days.
V841 Ophiuchi was a bright nova discovered by John Russell Hind on 27 April 1848. It was the first object of its type discovered since 1670. At the time of its discovery, it had an apparent magnitude of 5.6, but may have reached magnitude 2 at its peak, making it easily visible to the naked eye. Near peak brightness it was described as "bright red" or "scalet", probably due to Hα line emission. Its brightness is currently varying slowly around magnitude 13.5. The area of the sky surrounding this nova had been examined frequently by astronomers prior to the nova's discovery, because it was near the reported location of "52 Serpentis", a star John Flamsteed had included in his catalogue with erroneous coordinates.
V368 Aquilae, also known as Nova Aquilae 1936 no. 2 was the second nova which occurred in the constellation of Aquila during 1936. It was discovered on a photographic plate by Nils Tamm at Kvistaberg Observatory on 7 October 1936. At the time of discovery it was at photographic magnitude 7, and was already fading. Pre-discovery photographs showed that peak brightness occurred around 25 September 1936, at which time it had reached apparent magnitude 5.0, making it visible to the naked eye. The nova was described as being fiery red due to strong Hα emission, and for a time could be seen with binoculars simultaneously with V356 Aquilae, another nova which Nill Tamm had discovered a month earlier.
QZ Aurigae, also known as Nova Aurigae 1964, was a nova which occurred in the constellation Auriga during 1964. It was discovered by Nicholas Sanduleak on an objective prism photographic plate taken at the Warner and Swasey Observatory on 4 November 1964. Examination of pre-discovery plates from Sonneberg Observatory showed that the eruption occurred in early February 1964, and it had a photographic magnitude of 6.0 on 14 February 1964. Its brightness declined in images taken after the 14th, suggesting that its peak brightness was above 6.0. It was probably visible to the naked eye for a short time.
WR 133 is a visually moderately bright Wolf-Rayet star. It is a spectroscopic binary system containing a Wolf-Rayet primary and a class O supergiant secondary. It is in the constellation of Cygnus, lying in the sky at the centre of the triangle formed by β and γ Cygni, near η Cygni. It is the brightest member of the sparse open cluster NGC 6871.
