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.
The Vela Supernova is the remnant of a supernova explosion that occurred in the Vela constellation about 11,000 to 12,300 years ago. It is located about 800 light-years away from Earth and is one of the closest known supernova remnants to us.
A supernova can't occur on any planet. A supernova occurs when a very large star, at least 8 times more massive than the sun dies.
It is difficult to predict when a supernova will occur in our galaxy. However, if one were to happen in the Milky Way, it could be visible to us within a matter of days or weeks after the initial explosion, depending on its proximity to Earth.
No, it is not possible for Earth to go supernova. Supernovae occur in massive stars when they run out of nuclear fuel and collapse under their own gravity, Earth is not massive enough to undergo such a process.
There is no evidence of a supernova directly hitting Earth. However, supernovae can release harmful radiation and cosmic rays that may have impacted Earth in the past, potentially causing mass extinctions.
About 50 to 100 light-years as the closest safe distance between Earth and a supernova. But, if a supernova to go off within about 30 light-years of us, that would lead to major effects on the Earth, possibly mass extinctions.
A Hypernova - especially if you are next to it. A black whole is dangerous, but only within the event horizon
For a supernova to directly destroy Earth, it would need to be less than 10 light years away. However, even if a supernova were to occur farther away, its effects on Earth's atmosphere and climate could still be substantial.
The Vela Supernova is the remnant of a supernova explosion that occurred in the Vela constellation about 11,000 to 12,300 years ago. It is located about 800 light-years away from Earth and is one of the closest known supernova remnants to us.
Much bigger. Earth is a relatively small planet, much smaller than even a dwarf star. A supernova is a very large star exploding.
cosmic rays
A supernova is an exploding star. The Earth would be instantly incinerated, of course. There is approximately zero chance this will ever happen, though. If there was a supernova near Earth ... it would depend on how near. Betelgeuse is a good candidate for a supernova "soon" (within the next million years or so). Scientists who have modeled supernova explosions don't expect it will have much of an impact. If a star nearer than Betelgeuse were to go supernova, then it might be more serious.
A supernova can't occur on any planet. A supernova occurs when a very large star, at least 8 times more massive than the sun dies.
Well, honey, Earth Day isn't dangerous. It's actually all about raising awareness and taking action to protect our planet. Now, if you're out there hugging trees and not watching where you're going, you might trip and fall, but that's on you, not Earth Day. So, be kind to the Earth, but also watch your step.
Light Speed. 186,000 mps
Dangerous. Novas, or supernovas. Tycho Brahe coined the phrase "nova stellarum" when a "new star" appeared in the night sky. We now know that he was observing a supernova, the death throes of a very massive star.
The nearest likely supernova candidate I know of is Betelgeuse, which is about 640 light years away, and is already well off the main sequence in a Red Giant phase. In order to seriously disrupt Earth, a supernova would probably have to be significantly closer than that.