Sea Life Wiped Out by Neutron Star Collision?

Memorize writes "Scientists report in the Journal of Astrophysical Letters that a mass extinction of marine life 450 million years ago might have been caused by radiation from an exploding star, such as a collision between two neutron stars, or a neutron star collapsing into a black hole. Such an event would cause a ten-second burst of gamma radiation, and if it occurred within our galaxy, it could have wiped out many species on earth. At least if astronomers find out that an asteroid is heading our way, we can do something about it, but if there is a gamma burst, we get no warning. And if we did, would there be any way to protect the planet?"

Scary Stuff

[DarkHelmet]

This is pretty scary...

I remember reading this a while back on the Wikipedia entry for the Permian Triassic Extinction Event (link [wikipedia.org]), but the Wiki entry quotes specifically that an extinction like this would only happen if the star were 10 parsecs, or 30 light years away.

Dr Melott in the article claims that a star like this would have to be 6,000 light years away, or closer. (That's more than 200 times the distance previously claimed.

Keep in mind the volume of a sphere is 4/3 pi r^3, so the volume of space that this would take up is increased by a factor of 8,000,000. I'd say, that the chance of this happening to us, therefore is increased by a factor of 8 million.

As I said before, scary stuff.

Yet another reason

[Janitha]

Yet another reason why the space program(s) in the whole world shout be given a high priority. Not just for technology, but ultimately for human survival in such occasion.

Black Holes Ain't

[amigoro]

From TFA: caused by neutrons colliding with blackholes

Didn't slashdot report that Black Holes don't exists [nature.com]

Whom am I to believe?

There is a solution

[fgl]

Dont just live on one planet. Seriously, if we had the technology to spread the species beyond our solar system, we wouldnt be taken out in one cosmic hit. Admittedly a gamma burst from coliding neutron stars would still take out a large portion of a galaxy. I seem to recall a sci fi novella about something like this. I must go look it up

Re:Yet another reason

[Dr. Spork]

Sorry to break it to you, but the radius of the harmful effect is supposed to be 6000 light years. I doubt we can disperse the population that much before we see this happen again.

Besides, all this does is strip off the ozone layer, which would mess with the marine food chain for a few years. It's not like it would bake people or anything. I'm sure we'll collectively do more damage to the sea than this sort of thing ever could. How fast will we destroy 60% of the ocean's species? I'm guessing something on the order of decades. If this is something we care about, we should be worrying about ourselves and not about imploding neutron stars.

lenny bruce is not afraid

[Leontes]

I've been fascinated by these kinds of events for a while. We live in a huge cosmos, full of billions and billions of stars, the fact is that we really could at any point be wiped out by thousands of chance events at any moment, that we wouldn't even see coming, that we right now know nothing about. If our reality as we know it suddenly got deleted for whatever reason, and we had no idea that it was coming, there would be no hindsight to be twenty-twenty about. Just another reason to live life well, while we still have the chance to. Now I feel like eating ice-cream.

Re:Scary Stuff

[LewsTherinKinslayer]

I've never understood the human reasoning of fear, especially as it applies to something like this. IANAAP (i am not an astro physicist,) but I bet there is a far better chance of being killed in a car or struck by lightning than being wiped out by a gamma radiation burst.

Granted, this could completely destroy the human race, but either way I'm dead, so my stake in it is over.

Re:Scary Stuff

[DarkHelmet]

Sure, but that's just you.

Something like this, you have absolutely no legacy whatsoever. No kids to carry things on, nobody left to remember you, none of your accomplishments mattering.

I, for one, don't want to see the human race become extinct, regardless of if it's in my lifetime or not.

Are we really this blind?

[Aximxp]

I think it's great how preoccupied so many people are about these completely obscure hypothetical apocalypse events. If life has been ticking for hundreds of millions of years without a hitch you can be damn sure that the least of our worries are going to be random gamma radiation. How about the fact that we've lost almost 50% of all types of tropical, mediterranean and temperate forests as well as 30% of deserts over the past 100 years. Stop staring at the sky waiting for asteroids and mythical dragons to swoop down and annihilate the human race, the SUV in your driveway is a much more likely candidate people...

Re:No - we're doomed.

[a1ok]

Any gamma burst from a single point will only fall on half the Earth's surface directly. What stops us from just hopping across to the other half, instead of needing scifi tech to survive?

For that matter, even without warning around half the world population would automatically be shielded - well if China and India were on the exposed side that might be much less than half though ;)

Re:Scary Stuff

[sbaker]

Humans are just the tool that our genes use to make more genes.

From that perspective, my personal death is NOT as important as the continuation of my children.

Most parents know this at the instinctual level.

The argument that says I'm going to die - what to I care about the rest of humanity - is clearly bogus for most humans. All life on earth strives harder to pass on genetic information than to survive as an individual. That's why we age - and why we fall apart much more rapidly after child-rearing age is past.

Re:Scary Stuff

[CodeBuster]

Most people currently living on this planet will not be remembered even fifty years after their death. There may be some family members one hundred years or so down the line who remembers your name, dates of birth and death, and a few meager facts such as your profession; perhaps your name will be in some government records for a few hundred years. However, once the last person who actually knew you as a living person is gone you will most likely be forgotten. In time even our current civilization will fall and all records written or otherwise of average people will probably not survive the chaos. In the grand scheme of history very few people are destined to achieve lasting remembrance. If empires, kings, tyrants, and conquerors have been forgotten how much less will an average modern person be remembered in the millennia ahead?

Re:bad reason for a space program

[ccmay]

Just about the only place you wouldn't be affected would be on the far side of a barren planet

Never mind that, what about the far side of THIS planet? I have a hard time believing that gamma rays could be much of a threat with 7,000 miles of rock and molten iron for shielding. Energy transmission falls off exponentially with linear increases in the thickness of your shielding, don't forget.

Unless it's the Big Bang reprised, I don't think any organism on the "dark side" of the Earth would suffer a bit of harm. And anything like a neutrino that could pass through the Earth would also (statistically, at least) sail right through you, leaving you untouched.

IANAA-p. I am not an astro-physicicst. Anyone see any flaw in my argument?

Re:No - we're doomed.

[Roger W Moore]

I suppose we could make a REALLY good predictive model of when astronomical objects are likely to do this - and predict the arrival of a gamma ray burst in time to do something about it. But what could we possibly do?

According to the article the burst has to originate within 6,000 light years...so if we work out what causes them all we have to do is scour the near vicinty for the pairs of neutron stars required (if that's it). Not trivial but not impossible either. Once we've done that we will likely be able to predict when the burst will occur.

...but this radiation will be expanding out equally in all directions from the source.

Not neccessarily - it depends on the source.

we'd have to high-tail it outta here at close to the speed of light in order to get far enough away for the inverse-square law to have an effect.

Actually you don't need to worry about the inverse square law if you are going that fast. Red shift will make the gamma's harmless.

...and a mile of salt water doesn't attenuate the energy enough

If you actually read the article (but this is Slashdot so what am I talking about!) you'll see that the effect is caused by interaction between the gammas and the ozone layer. If the gammas had enough energy (or intensity) that a significant dose penetrated 1.6km of water the heat load would actually be what would kill you and not the radiation itself! Such a massive heat load would have melted rocks etc and, I would guess, leave a significant geological record. In any case there is no way the burst could penetrate the earth and affect life on the otherside directly which you scenario would require - otherwise no more than 50% of the earth could be affected and the seas far less than the land due to the water shielding.

Re:It doesn't seem quite so scary to me

[ozbird]

Slight nitpick: You should worry about whether it blew up 8,000 years ago - that's how long it will take for the light (and any GRB) to reach here. If it blew up tomorrow, we wouldn't know for another 8,000 years.

Re:Scary Stuff

[Jamu]

Genes don't have a perspective. Nor do they grade anything in levels of importance. Genes create more genes because otherwise we wouldn't call them genes. We fall apart because this is a natural process in any system. It's also obvious that genes will be passed on before sexual dysfunction.

Re:Scary Stuff

[Alioth]

However, I don't go worrying about being hit by a car continuously, because I can mitigate the risk of being hit by a car, and if I do get hit by a car, the entire human race doesn't perish.

A random gamma ray burst on the other hand I can do nothing about. [0] Since a big part of our point is the continuation of our race as a whole (we are genetically predisposed to want to do this), we will also be hard wired to fear events that can totally end the entire genetic line of our species. Also, I expect a death by gamma ray burst would be drawn out and deeply unpleasant. Dying of radiation poisoning whilst watching everyone around you do the same thing will be a pretty nasty event.

[0] No, I don't actually sit around worrying about gamma ray bursts, in fact I give it very little thought. I give much more thought to ways of avoiding being run down by cars.

Gamma Rays

[kangpeh]

Technology has advanced considerably when compared to 450 million years in the past. When it comes to gamma rays and so forth, if you consider the fact that life exists on the planet now, ironically, an asteroid hitting the planet would have a much larger inpact than a starburst. In the case of a starburst, with the help of radioactive precautious measures such as lead and a little bit of water, we can taste the rainbow.

Not nearly good enough.

[devphil]

Surviving the first 10 seconds is not the problem. Surviving the next 30 years is the problem.

There have been many articles and papers and whatnot published over the last several years, all proposing different models of what happens when Earth gets hit by a gamma-ray burst. They all point to Very Bad Things happening to the atmospheric layers, which then has a cascading effect.

Fine, you survive the first 10 seconds, but none of the crops did. Growing new crops in time to feed anyone is problematic when the UV shielding is gone. Reactions in the lower atmosphere would likely form a fair deal of the chemicals that result in "acid rain", so once you're wearing 100% UV sunscreen and can go outside, you still can't grow anything. Etc, etc.

Because people don't understand large numbers?

[Moraelin]

From my limited observation, most people tend to have a "compressed" (for lack of a better word) perception of large distances, weights or times. Sort of like Terry Pratchett's trolls, whose counting skills went "one, two, lots", but on a larger scale. Beyond a limit, for the vast majority of humans anything is just "lots". I mean, picture one human in your mind. You can do that. 10 humans? No problem. 1000 humans? How about one _billion_ humans? It's, uh, "lots". Do you know how long a day is? Not just theoretically, I mean. Well, yes, you experience that time interval every day. How about a year? It still works. How about a _billion_ years? Try to really imagine that interval in your head. It's, uh, "lots" of time. In practice, for most humans the "lots" limit is even lower. E.g., people have no trouble treating intervals like 20,000 years of a SF universe's history as a blip where nothing noteworthy happened. Yeah, sure, for 20,000 years noone designed a new ship or generally invented anything new. Now think that in half that time RL humans moved from living in caves to launching spaceships. (The first known city is less than 10,000 years old.) So in fact, that "20,000 years" interval is perceived as a _much_ smaller one. Once you've reached the "lots" limit, everything above that is the same. If someone's "lots" limit for time is, say, 20 years, anything over that will be the same. Be it 20,000 years or a billion years, is in fact perceived as the exact same as 20 years. Hence our fascination with stuff that could happen in a billion years or several billion years. (E.g., that our sun will eventually kill us all.) Because instinctively we perceive it at a much closer point in the future. It's in the same "lots" range a your kids' going into retirement. (Incidentally, and just for the sake of a tangent, most people's inability to comprehend evolution. Stuff like billions of billions of billions of organisms, over billions of years, gets compressed to the same "lots" range as 100 cows on a farm over 20 years. And, duh, noone saw those evolve into something else.) Well, it's just a wild hypothesis. I could well be wrong.

Re:Scary Stuff

[shiba_mac]

Surely this wouldn't actually kill us all?

If the burst are "extremely short", only ~half the surface of the planet would be affected. Sure this kills all the plankton, and does a shedload of damage to the biosphere, but would it actually wipe out humanity? Even humans on the wrong side of the planet are a lot hardier than plankton. And we have other ways of making food,that aren't dependant on crops and animals. Sure, we don't use them a whole lot atm, but if we had to, we probably could.

Mightn't be able to supply everyone, but enough people surely to ensure continuance of the race.

same with any global catastrophy

[FudRucker]

be it a gamma ray burst, meteor/comet collision or a volcano eruption big enough to destroy the environment, if any of the above happens it is much to big for humans to control and it would doom humanity to extinction...

Re:Scary Stuff - Child rearing

[cheesybagel]

Stress is overrated. People think they have it so hard these days. How about back when your food easily could kill you (mammoth trample), you had to run and struggle to catch your food, you had to walk miles everyday to get food, or move to a place with food or water, etc.

Stress is a symptom of other problems, not a cause, the way of your body telling you you are doing something very wrong in maintaining it. The sooner everyone realizes this, the happier they will be.

Re:Scary Stuff

[saider]

That's why we age - and why we fall apart much more rapidly after child-rearing age is past.

The reason we age is because there is no selection mechanism for longevity. Diseases that affect us after we pass on our genes do not affect our ability to pass on our genes. Once people have their children, their genes are passed on and they are deemed "successful". People who die shortly after the birth of their children are on the same footing as those who live to 100, from a natural selection point of view.

Re:Ah, yes: the selfish gene

[ergo98]

Learn what a paragraph is. When you've created the executive summary maybe we'll give it a read.

Re:Scary Stuff

[radtea]

Humans are just the tool that our genes use to make more genes.

If so, they've chosen a fantastically inefficient way to do it, haven't they? You could have a dozen kids, and still lose 0.024% of your genes forever. If you have two kids, a full 1/4 of your genes would never be transmitted to posterity.

Sexual reproduction is a good trade-off for an organism, but a terrible deal for the organism's genes.

--Tom

Re:Scary Stuff - Child rearing

[fossa]

Ah, but we evolved to run after food every day, and survive without when we couldn't catch it. Modern life has changed faster than evolution can keep up. We aren't made to sit in a cubicle all day. We aren't made to drive cars everywhere, or get a meal whenever we want it, or play video games after sitting in a classroom all day. Hence many problems from living a modern life; American obesity comes to mind.

Re:Scary Stuff

[Anonymous Coward]

You're obviously not a Mormon..

Re:not anymore

[q-the-impaler]

In the context of spreading genes, what makes humans so different from animals, or protozoans? Do they not count simply because we cannot perceive their desire to procreate?

Further, are human morals, theories, and ideas more important to spread than those of protozoans? And before you answer that they do not have any of those, I challenge you to irrefutably prove it.

Now that you realize you are a miniscule and insignificant creature (like the rest of us), go home and cry and welcome your gamma-ray overlords.

Re:Scary Stuff - Child rearing

[q-the-impaler]

What's worse now is that people self-medicate to reduce the same stresses that people experienced in prehistoric times. Used to be that if you couldn't handle the stress your carcass was quickly eaten by carrion birds. Now we have all these weak genes flowing rampantly through our pools, simply because we are 'civilized.' The thought of it leads me to drink. Now where's my Prozac?

Re:Where's the raw data?

[drooling-dog]

We want to have control, even over our deaths, even though we know, logically that we have very little real control.

I'm not sure that's the principal reason we invented religion, but it is one of the main reasons for its broad appeal...

Re:Scary Stuff - Child rearing

[Mindwarp]

Like hearing my 2.5 year old son giggle manically when we spot him peeking through our bedroom door at 7:00am. Like seeing grandma's face when she says "See the sun going down?" to our five year old daughter and our daughter says "Actually the sun stays still - the part of the Earth we live on is just turning away from it." Like having two little guys who are small enough to crawl under Daddy's desk and help him fish cables, and who get such an enormous kick from doing it. I'll now return you to our normal Slashdot cynicism :)

Re:Scary Stuff - Child rearing

[cheesybagel]

A fever is also a symptom and fever also kills. A symptom can get to the point where it is worse than the problem it is signalling.

Re: The Biology of Senesence

[lgw]

Laws of thermodynamics and entropic considerations ultimately dictate that organized (non-random) systems will eventually decay toward randomness.

This argument is so often used falsely about biological systems that it needs correcting (even though I doubt you intended to sound like a creationist). Organized systems will decay towards randomness without energy input. Fortunately there's this huge fusion furnace in the sky dumping energy into the system like crazy.

There may well be a reason why organized systems tend to have limited duration, but it's not thermodynamics!

Half Extinction

[richyoung]

Wouldn't it just destroy the portion of the human race (and other species) on the half of the globe facing the burst source? An entire planet's worth of soil, rock, magma, etc. makes a pretty good shield.
Humanity is certainly positioned to survive such an event, though many wild species lack our enviable dispersion and would not.

Re:Scary Stuff - Child rearing

[Vip]

Like the screams of joy as you walk through the door after work, making you forget all the stuff that happened at work that day? And the next day they ask if you can stay home from work...and you do. Who else would you do that for?

Or the sheer wonderment and joy on their faces as they experience something new to them, that you take for granted everyday. (Think elevators for a minute, or escalators until security shows up :-)

Or doing the inevitable childrens damage to themselves, and crying, yet a kiss from you wipes all the tears and pain away. And then in return offering you a kiss when you say "Ow!"

Or maybe last week, when Daddy was sick, how my 2.5 year old was concerned enough to get me my
medicine (really just vitamin C tablets) and juice and water. Concerned enough to come up with "Daddy has to lie down, get better! No 'puter!!"

Or perhaps how they have a different view of things, in that they can teach you as much as you teach them.

I could go on and on...

"during the process of raising children you get worn out physically and mentally. I'm thinking all the late nights, interrupted sleep, emotional and physical drain of being in close contact with children."

Never looked at it that way. You are correct in a way....but it's all worth it.

Vip