Nova Stars are essentially giant fusion reactions occurring in the vacuum of space.
Because stars have so much mass, they possess powerful gravitational forcebut they don’t collapse because of the outward force generated by nuclear fusion, continually converting hydrogen atoms to helium.

Sometimes stars begin orbiting each other, forming a binary star system. Typically this involves a white dwarf star and a red giant. Orbiting the red giant like a moon, the dwarf star rips matter from its companion until it essentially gags on the excess, coughing hot gas and radiation into space. This dramatic phenomenon is relatively common, and the white dwarf is not destroyed in the resulting nova.

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