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.)
A hypernova is a more powerful and larger explosion than a supernova. It occurs when a massive star collapses and releases an immense amount of energy, much greater than that of a supernova. Hypernovae are one of the most energetic events in the universe.
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
A supernova, or in the case of a smaller star, a nova.
The range of masses for a supernova typically falls between about 8 to 50 times the mass of the sun. When a star that massive runs out of nuclear fuel, it undergoes a catastrophic collapse resulting in a supernova explosion. Smaller stars may end their lives in a different type of explosion called a nova.
In the case of a star (that is not actually going nova or supernova) they are balanced.
A hypernova is a more powerful and larger explosion than a supernova. It occurs when a massive star collapses and releases an immense amount of energy, much greater than that of a supernova. Hypernovae are one of the most energetic events in the universe.
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
No. Antares is 883 times the diameter of the sun, which makes it one of the largest stars by the amount of space it takes up. But, Antares is only 15 times the weight of our sun. A star has to be somewhere around 100-300 times heavier to go hypernova. So while it's quite large, unfortunately (or fortunately since it is so close to Earth) it isn't dense enough to go hypernova.
About 20 years.
A nova or a supernova
A super nova isn't a person. A super-nova is a high mass star's explosion.
The difference is 11 hours.