2007-05-14 05:50:32 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
The blast from a supernova is not instantaneous, it's a stream of hard radiation that would bathe this solar system for a long, long time. It wouldn't make a bit of difference which hemisphere was facing towards it when it's first detected.
2007-05-14 06:30:02 · answer #1 · answered by gamblin man 6 · 1⤊ 1⤋
Most likely, the increased radiation by itself would not be enough. What would happen is the radiation from a supernova would trigger chemical reactions in the upper atmosphere that resulted in the ozone layer decaying. *That* is what would devastate all life on Earth. The ozone layer across the entire planet would be destroyed, even if only one side of the Earth were exposed to the intense radiation. In fact, this may have happened about two million years ago.
2007-05-15 17:26:50 · answer #2 · answered by Horatio 3 · 0⤊ 0⤋
First, the practical. There are no stars within 10 light years of the earth that can supernova so this will not come to pass.
Second, the theoretical. If it were close enough, and it really can't be, it would indeed devastate all life on earth. About the hemisphere question: it would be basically in the same plane as the earth and it would blast across us for more than a day, and more than one wavefront would reach the earth, so the earth would rotate all itself into the wavefront. So there would be no saving throw. In any case, wiping out life in one half of the earth would have extraordinary and likely devastating effects on the other half even it it were not irradiated.
Likelier is an in between situation in which life is irradiated in a short, but nasty burst. Several of them over a fairly short period of time. Many types of life would be badly affected, but many others would be less so. Bears in hibernation for instance would be less so. Birds nesting on cliffs, likely more so. Likely none would be killed, just damaged in a way leading to cancer. And in many cases, their future young would not suffer any particular damage. Animals in water would likely suffer far, far less than land animals. Honestly, I do not know how radiation in large, but non-continuous doses affects plants. But affect them it would. My guess would be that grasslands would suffer more than jungle (oh, um, sorry, um, rainforest... have to be PC, even with plant names...) due to the radiation hammering the top cover layer which is the only layer in grasslands vs. one of many in jungle.
All this also depends on the earth's Van Allen belt. Which in turn depends on the cycle of the earth's magnetic field which sometimes is strong and sometimes weakens while moving about under the surface, changing direction from time to time. The stronger the belt, the better for life on earth. On the other hand, if we were near the end of a weak cycle, with the life on earth having gone through a few thousand years of extra harm and adapting to it, perhaps we would be even better placed to handle the supernova radiation waves than during a strong belt period due to life having evolved along toward handling such radiation better due to the harsher than present radiation setting.
Good thing it can't happen, eh? Why find out when only being able to argue about it means we all don't have to risk dying out from such a thing?
2007-05-14 13:31:35 · answer #3 · answered by Mike T 2 · 1⤊ 0⤋
10 light years away is extremely close! Even a supernova that is 150 light-years away could devastate our fragile biosphere (it's really only stable under the radiation from our sun). See http://www.newscientist.com/article.ns?id=dn2311 .
2007-05-14 13:30:31 · answer #4 · answered by Ron 6 · 1⤊ 1⤋
It would blast the WHOLE earth to smithereens. Remember that the radition from the blast lasts fo decades, so it´ll be goodbye to all of us.
2007-05-15 00:06:50 · answer #5 · answered by inesmon 5 · 0⤊ 0⤋
Hi. It would destroy all life at only 10 light years away. The oceans would boil away so even life at the undersea vents would not survive.
2007-05-14 13:18:50 · answer #6 · answered by Cirric 7 · 1⤊ 1⤋
The earth spins every 24 hours dude. Even if it happend to hit at the norhtern or souther pole, depending on it's strength, it could destroy all life on earth. Except maybe the bacteria/viruses and maybe cockroaches :-)
2007-05-14 12:52:47 · answer #7 · answered by Anonymous · 0⤊ 2⤋
It won't do anything, because it would be to far away.
2007-05-14 13:07:50 · answer #8 · answered by spir_i_tual 6 · 1⤊ 3⤋