A Nova [See Link] is a fusion reaction in the accretion layer (the superficial shell) of a white dwarf star, which is slowly stealing material from a companion in a binary system. In the case of an instability in the accretion disk itself, the event is called a dwarf nova.
This can occur once or many times. RS Ophiuchi has erupted in 1898, 1933, 1958, 1967, 1985, and 2006. It is in it's "quiet" phase at the moment, but will more than likely erupt again in the future.
If a nova accretes enough mass to pass the Chandrasekhar limit then the whole star will explode as a type I-a supernova.
A Supernova [See Link] is the catastrophic destructive event caused by the core collapse of a large star.
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The term "nova" is generically applied to exploding stars, but is more technically a flare-up of fusion activity on the outer surface of a white dwarf star. A "supernova" is a more extreme version involving the gravitational collapse of a very large star. In this process, the outer layers fall in on the star's core, then are violently blasted away.
A supernova is therefore the "death" of a star, as fusion will normally end afterward, leaving a neutron star or black hole. The explosion also creates a nebula of illuminated gas that is one of the most visible of all celestial phenomena.
The supernova process is caused by the exhaustion of nuclear "fuel" (lighter elements) within the star, so that the reactions are no longer able to resist the gravity trying to compress the solar mass into the core. The star collapses, causing the outer layers to violently explode outward as gases and dust. The remnant core may become a super- compressed neutron star or possibly a black hole.
(For details on "nova", see related questions and link.)
(For details on "supernova remains" see related question and link.)
Some nebulae are formed from massive supernova explosion. The material thrown off from this is ionized by the supernova remnant. One example is the Crab Nebula, in Taurus. It is the result of a recorded supernova, SN 1054, in the year 1054 and at the centre of the nebula is a neutron star, created during the explosion.
ANebula is a conglomeration of gas usually lit up or excited into luminescence by nearby stars. A Neutron star is a star that has collapsed into a very small (for a star) sphere so that its entire density is that of the nucleus of an atom.
Our Sun would have a diameter of about 20 km (the length of Manhattan) if it were to collapse into a neutron star.
A supernova explosion is the death of a massive star, which normally leaves behind either a neutron star or a black hole. So a supernova is like a campfire, while a neutron star is like the burnt-out log that's left when the fire goes out.
A Nebula is a cloud of interstellar dust, hydrogen gas, helium gas and plasma, whereas a supernova is the explosion of a massive star.
See related link for more information
A supergiant is a star that has expanded to at least 100 times the diameter of the sun. A supernova is an exploding star.
A supergiant is a very large star, whereas a supernova is the death of a supergiant when it explodes.
A supernova is where a massive star explodes, a neutron star is the remnant of a supernova explosion - a black hole is the other possibility.
See related questions.
See related questions
A hypernova [See related question]
When you think of a star think of something like the sun, while a supernova is the explosion of a star, while its at the ending of its life span. Star: "A star is a massive, luminous ball of plasma that is held together by its own gravity." Supernova: "A supernova (plural: supernovae) is a stellar explosion." Stellar: "Stellar is an adjective referring to one or more stars." Quotes are from: http://en.wikipedia.org/wiki/Supernova
Nova (plural novae) means "new" in Latin, The prefix "super-" distinguishes supernova from ordinary nova.
A supernova, or in the case of a smaller star, a nova.
A Nova or a Supernova.
A hypernova [See related question]
When you think of a star think of something like the sun, while a supernova is the explosion of a star, while its at the ending of its life span. Star: "A star is a massive, luminous ball of plasma that is held together by its own gravity." Supernova: "A supernova (plural: supernovae) is a stellar explosion." Stellar: "Stellar is an adjective referring to one or more stars." Quotes are from: http://en.wikipedia.org/wiki/Supernova
Nuclear fusion stops and the star is no longer capable of transformming LIGHTER elements into HEAVIER. elements. At this point GRAVITY looses out and PRESSURE wins out thereby causing the supernova explosion. But bear in mind, there is a HUGE difference between an ordinary star going NOVA and a SUPERNOVA.
super nova
A supernova is when a massive star explodes. A neutron star is what can be formed after a supernova explosion. See related questions
A nebula contains stars and other matter; a supernova is just a large enough nova, or star that explodes at the end of its life cycle due to spent fuel
Supernova
A nova or a supernova
A super nova isn't a person. A super-nova is a high mass star's explosion.
Nova (plural novae) means "new" in Latin, The prefix "super-" distinguishes supernova from ordinary nova.
About 20 years.
A supernova, or in the case of a smaller star, a nova.