When is the Sun predicted to go nova?

The Sun will never go nova. A nova explosion requires that the star have a nearby companion star that is a white dwarf, and that the primary star is an evolved red giant shedding mass. When enough of this mass is accreted by the white dwarf, it detonates on the white dwarf's surface to produce a nova (see Glossary). The Sun has no companion star close enough to make this happen. If it did, habitable planets like Earth would not exist. We also know that some stars produce super-flares, especially the very cool M-dwarfs. These flares could be luminous enough to melt the surfaces of the moons of Jupiter.

The Sun does not appear to be the kind of star that would unexpectedly unleash such a lethal event. Lunar rock samples have tracks within their crystalline structure left over from energetic particles, and geologists have used this information to estimate that our Sun has not produced any flares that are 10-times as bright as the biggest we have seen so far, over the last 100 million years.

This answer was updated in 2011. See my books: The Astronomy Cafe (1998) and Back to the Astronomy Cafe (2003) for more FAQs in printed form. Author: Dr. Sten Odenwald, Copyright 2011

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