That depends entirely on how far the supernova is from Earth. If it is our Sun going supernova, a little over 8 minutes. And a few Milli-seconds later all life on Earth would be gone. Any other star, it would just appear slightly brighter for a while and then disappear. It could take centuries for the light to reach us.
The light of the explosion wouldn't arrive at the Earth for 500 years.
A near Earth supernova [See Link] is a supernova that occurs close enough to the Earth (less than 100 light-years away) to have noticeable effects on its biosphere. Gamma rays from a supernova 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. This has been proposed as the cause of the Ordovician extinction - [See link], which resulted in the death of nearly 60% of the oceanic life on Earth. Type Ia supernova [See Link] are thought to be potentially the most dangerous if they occur close enough to the Earth. Because these supernova occur 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. The closest known candidate is IK Pegasi [See Link] Recent estimates predict that a Type II supernova would have to be closer than 26 light-years to destroy half of the Earth's ozone layer.
along long long long time
It would take.. 2160 Hours. or 90 Days.
That depends on how far away the star is. If the exploding star is 1,000 light years away we would see the supernova 1,000 years later. If it is 2,000 light years away we would see it 2,000 years later.
6,300 years
The light of the explosion wouldn't arrive at the Earth for 500 years.
Supernova(SN) 1054 Crab Supernova was first seen in 1054, it is estimated to be 6,500 light years away, so 6,500 years
It would take about a month.
It would take 120 years to go to the center of earth
A near Earth supernova [See Link] is a supernova that occurs close enough to the Earth (less than 100 light-years away) to have noticeable effects on its biosphere. Gamma rays from a supernova 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. This has been proposed as the cause of the Ordovician extinction - [See link], which resulted in the death of nearly 60% of the oceanic life on Earth. Type Ia supernova [See Link] are thought to be potentially the most dangerous if they occur close enough to the Earth. Because these supernova occur 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. The closest known candidate is IK Pegasi [See Link] Recent estimates predict that a Type II supernova would have to be closer than 26 light-years to destroy half of the Earth's ozone layer.
it just won't take long
it would take 88 earth days to orbit the sun so it is 1/4 earth years.
Easy answer: it would take 72 years.
10MIN
3 DAYS
around to ten years