Nova

recurrent novanovaeclassical novanew starclassic novaenormously bright starfar too small to explodehelium novaits star went novaN
A nova (plural novae or novas) or classical nova (CN, plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months.wikipedia
435 Related Articles

Binary star

spectroscopic binaryeclipsing binarybinary
All observed novae involve closely located binary stars (the progenitors), either a pair of red dwarfs in the process of merging, or a white dwarf and another star.
Binary stars are also common as the nuclei of many planetary nebulae, and are the progenitors of both novae and type Ia supernovae.

Cataclysmic variable star

cataclysmic variablecataclysmic variablescataclysmic
They are all considered to be cataclysmic variable stars.
They were initially called novae, from the Latin 'new', since ones with an outburst brightness visible to the naked eye and an invisible quiescent brightness appeared as new stars in the sky.

Dwarf nova

SU UMa variableSS Cyg variableSU Ursae Majoris
The main sub-classes of novae are classical novae, recurrent novae (RNe), and dwarf novae.
novae) is a type of cataclysmic variable star consisting of a close binary star system in which one of the components is a white dwarf that accretes matter from its companion.

Supernova

supernovaecore-collapse supernovasupernovas
Also with similar names are the much more energetic supernovae (SNe) and kilonovae. During the sixteenth century, astronomer Tycho Brahe observed the supernova SN 1572 in the constellation Cassiopeia.
Supernovae are more energetic than novae.

Transient astronomical event

transientastronomical eventastronomical transient
A nova (plural novae or novas) or classical nova (CN, plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months.
Singularly, the term is used for violent deep-sky events, such as supernovae, novae, dwarf nova outbursts, gamma-ray bursts, and tidal disruption events, as well as gravitational microlensing, transits and eclipses.

Luminous red nova

Luminous red novae share the name and are also cataclysmic variables, but are a different type of event caused by a stellar merger.
Luminous red novae are not to be confused with standard novae, explosions that occur on the surface of white dwarf stars.

List of novae in the Milky Way galaxy

frequently
They occur far more frequently than galactic supernovae, averaging about ten per year.
This is a partial list of novae in the Milky Way galaxy that have been discovered and recorded since 1891.

Nova remnant

A few novae produce short-lived nova remnants, lasting for perhaps several centuries.
A nova remnant is made up of the material either left behind by a sudden explosive fusion eruption by classical novae, or from multiple ejections by recurrent novae.

Tycho Brahe

BraheTycho1572 supernova
During the sixteenth century, astronomer Tycho Brahe observed the supernova SN 1572 in the constellation Cassiopeia.
His precise measurements indicated that "new stars" (stellae novae, now known as supernovae), in particular that of 1572, lacked the parallax expected in sublunar phenomena and were therefore not tailless comets in the atmosphere as previously believed but were above the atmosphere and beyond the moon.

Kilonova

kilonovae
Also with similar names are the much more energetic supernovae (SNe) and kilonovae.
The term kilonova was introduced by Metzger et al. in 2010 to characterize the peak brightness, which they showed reaches 1000 times that of a classical nova.

SN 1572

1572TychoTycho's Supernova
During the sixteenth century, astronomer Tycho Brahe observed the supernova SN 1572 in the constellation Cassiopeia.
The appearance of the "new star" helped to revise ancient models of the heavens and to speed on a revolution in astronomy that began with the realisation of the need to produce better astrometric star catalogues (and thus the need for more precise astronomical observing instruments).

Thermal runaway

runawayrunaway reactionthermal explosion
Hydrogen fusion may occur in a stable manner on the surface of the white dwarf for a narrow range of accretion rates, giving rise to a super soft X-ray source, but for most binary system parameters, the hydrogen burning is unstable thermally and rapidly converts a large amount of the hydrogen into other, heavier chemical elements in a runaway reaction, liberating an enormous amount of energy.
In astrophysics, runaway nuclear fusion reactions in stars can lead to nova and several types of supernova explosions, and also occur as a less dramatic event in the normal evolution of solar mass stars, the "helium flash".

RS Ophiuchi

RS Oph
An example is RS Ophiuchi, which is known to have flared six times (in 1898, 1933, 1958, 1967, 1985, and 2006).
RS Ophiuchi (RS Oph) is a recurrent nova system approximately 5,000 light-years away in the constellation Ophiuchus.

V1500 Cygni

Nova Cygni 1975V1500 Cyg
The brightest recent example was Nova Cygni 1975.
V1500 Cygni or Nova Cygni 1975 was a bright nova occurring in 1975 in the constellation Cygnus.

Super soft X-ray source

VY Scl starNL/VY Scl variablesuper-soft x-ray source
Hydrogen fusion may occur in a stable manner on the surface of the white dwarf for a narrow range of accretion rates, giving rise to a super soft X-ray source, but for most binary system parameters, the hydrogen burning is unstable thermally and rapidly converts a large amount of the hydrogen into other, heavier chemical elements in a runaway reaction, liberating an enormous amount of energy.
Those with luminosities below ~3 x 10 38 erg/s are consistent with steady nuclear burning in accreting white dwarfs (WD)s or post-novae.

Accretion (astrophysics)

accretionaccretingplanetary accretion
When the orbital period falls in the range of several days to one day, the white dwarf is close enough to its companion star to start drawing accreted matter onto the surface of the white dwarf, which creates a dense but shallow atmosphere.
Occasionally, this can result in stellar surface fusion (see Bondi accretion).

V339 Delphini

V339 Del
The most recent were V1280 Scorpii, which reached magnitude 3.7 on 17 February 2007, and Nova Delphini 2013.
V339 Delphini or Nova Delphini 2013 (PNV J20233073+2046041) is a bright nova star in the constellation Delphinus.

White dwarf

white dwarfswhite dwarf starcentral star
All observed novae involve closely located binary stars (the progenitors), either a pair of red dwarfs in the process of merging, or a white dwarf and another star.
The spectra of these novae exhibit abundances of neon, magnesium, and other intermediate-mass elements which appear to be only explicable by the accretion of material onto an oxygen-neon-magnesium white dwarf.

V445 Puppis

The theory was first proposed in 1989, and the first candidate helium nova to be observed was V445 Puppis in 2000.
V445 Puppis was a nova in the constellation Puppis.

Nova Centauri 2013

The last bright nova was V1369 Centauri reaching 3.3 magnitude on 14 December 2013.
Nova Cen 2013 or V1369 Cen (PNV J13544700-5909080) was a bright nova in the constellation Centaurus.

V1280 Scorpii

V1280 Sco
The most recent were V1280 Scorpii, which reached magnitude 3.7 on 17 February 2007, and Nova Delphini 2013.
V1280 Scorpii (or Nova Scorpii 2007) is a nova observed in February 2007 in the constellation Scorpius, just south of M62.

Symbiotic nova

symbiotic
NC: very slow novae, also known as symbiotic novae, staying at maximum light for a decade or more and then fading very slowly.
Symbiotic novae are slow irregular eruptive variable stars with very slow nova-like outbursts with an amplitude of between 9 and 11 magnitudes.

Type Ia supernova

type Iatype 1a supernovatype Ia supernovae
Eventually, the white dwarf could explode as a Type Ia supernova if it approaches the Chandrasekhar limit.
The theory of this type of supernova is similar to that of novae, in which a white dwarf accretes matter more slowly and does not approach the Chandrasekhar limit.

Roche lobe

donor starRoche-lobemass transfer
The second star—which may be either a main sequence star or an aging giant—begins to shed its envelope onto its white dwarf companion when it overflows its Roche lobe.
Mass transfer due to Roche-lobe overflow is responsible for a number of astronomical phenomena, including Algol systems, recurring novae (binary stars consisting of a red giant and a white dwarf that are sufficiently close that material from the red giant dribbles down onto the white dwarf), X-ray binaries and millisecond pulsars.

John Birmingham (astronomer)

John BirminghamJ.Birmingham
In 1866 he discovered the recurrent nova T Coronae Borealis.