Is this true?

Question

If a supernova happened to with a nearby star the earth could be destroyed? How could this happen if the nearest star is 4 light years away? Thats an unbelievable distance for the explosion to travel! I guess supernovas are very powerful events! Could this have happened to the earth before?

Answer 1

Yeah its true.

A supernova (pl. supernovae) is a stellar explosion which produces an extremely bright object made of plasma that declines to invisibility over weeks or months. A supernova briefly outshines its entire host galaxy. It would take 10 billion years for the Sun to produce the energy output of an ordinary Type II supernova. Stars beneath the Chandrasekhar limit, such as the Sun, are too light to ever become supernovae and will evolve into white dwarfs.

A near-Earth supernova is an explosion resulting from the death of a star that occurs close enough to the Earth (roughly fewer than 100 light-years away) to have noticeable effects on its biosphere. Gamma rays are responsible for most of the adverse effects a supernova can have on a living terrestrial planet. In Earth's case, gamma rays induce a chemical reaction in the upper atmosphere, converting molecular nitrogen into nitrogen oxides, depleting the ozone layer enough to expose the surface to harmful solar and cosmic radiation. The gamma ray burst from a nearby supernova explosion has been proposed as the cause of the end Ordovician extinction, which resulted in the death of nearly 60% of the oceanic life on Earth.

Speculation as to the effects of a nearby supernova on Earth often focuses on large stars, such as Betelgeuse, a red supergiant 427 light-years from Earth which is a type II supernova candidate. Several prominent stars within a few light centuries from Sol are candidates for becoming supernovae in as little as a millennium. Though spectacular, these "predictable" supernovae are thought to have little potential to affect Earth. Type Ia supernovae, though, are thought to be potentially the most dangerous if they occur close enough to the Earth. Because Type Ia supernovae arise from dim, common white dwarf stars, it is likely that a supernova that could affect the Earth will occur unpredictably and take place in a star system that is not well studied. One theory suggests that a Type Ia supernova would have to be closer than a thousand parsecs (3300 light years) to affect the Earth.

Recent estimates predict that a Type II supernova would have to be closer than eight parsecs (twenty-six light years) to destroy half of the Earth's ozone layer. Such estimates are mostly concerned with atmospheric modeling and considered only the known radiation flux from SN 1987A, a Type II supernova in the Large Magellanic Cloud. Estimates of the rate of supernova occurrence within 10 parsecs of the Earth vary from once every 100 million years to once every one to ten billion years.

Answer 2

For sure we would be goners. A supernova is the biggest event in the Universe. The closest neighbor that could explode in this manner is about 500 light years away, this is regarded as a safe distance. So it never happened before. The worst thing that could happen with a star is a huge solar flare from our own Sun. Of course we don't really know as a solar flare doesn't leave any trace in history but this event could be responsible for at least 2 of the major extincions in Earths history.

Answer 3

The earth is unlikely to be destroyed. However, a supernova releases so much radiation and energy, that the earth would be bombarded with very deadly gamma rays. The ozone layer would be severely damaged, allowing radiation to destroy much of the life on earth. There is a possibility this has happened before, and resulted in a mass extinction.

Answer 4

There are many different types of supernovas (classified type I, II, IIb etc...) The weaker types would only send low levels of gamma radiation towards earth, not causing any serious problems, so its likely this has happened before. The stronger types, type II for example, would completly destroy the earths atmosphere killing all life on the planet (if the star was within 26 lightyears) so its pretty unlikely this happened before, though not impossible.

Answer 5

A super nova close enough to earth would flood the earth with neutrinos and gamma rays that would probably kill all life on earth. The physical effects of mass may never get here!!

Answer 6

The Earth, you, and I are here in manifestation as the direct result of a supernova, and I'm sure it was not comfortable to anyone in the neighborhood.

A black hole with a quasar---man, that's real ghetto. Time to move to the suburbs...

Answer 7

True that. Not just love stories. It's foolishness to compare any part of life with movies.