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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?"
I remember reading this a while back on the Wikipedia entry for the Permian Triassic Extinction Event (link), 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.
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
From reading the article, it didn't seem like there was any evidence of this other than speculation. They talk about using computer models to show how it would have wiped life out, but what about the evidence that brought them to this model to begin with? They could at least start with evidence in rocks or something. I wish that every time I speculated on something, that they would 200 million dollar probe. I speculate that this comment will be modded up to +5 interesting, we should launch a probe to see if this is indeed the case.
And if we did, would there be any way to protect the planet?"
No.
Gee, I wish all "Ask Slashdot" postings were this easy..
On the bright side, gamma ray exposure is what brought us the Hulk, and his hot cousin She-Hulk. So hey, what's few million flavors of fish, give or take?
Tinfoil hats for everyone!
Shades of Grayden
I can confirm the veracity of the theory, I've actually reproduce it through experimentation. My partner and I set up a live and a control group and did a sequenced build up until... well...
So anyways, we put Sea Monkeys in a microwave oven.
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.
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/
Since gamma rays are travelling at the speed of light - we can't possibly get any warning of them without figuring out some kind of faster-than-light transportation or message transmission.
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?
It takes a good few inches of lead (or a good few feet of concrete, dirt, whatever) to significantly attenuate gamma rays - and if the ones were are talking about were powerful enough to get through the full depth of the earth's oceans and still kill things when they got there - then you'd need to wrap the earth in a few feet of lead - or hide down some amazingly deep mine-shafts.
Since gamma rays are electrically neutral, you can't deflect them away with magnets or anything like that.
We'd have to get out of the way - but this radiation will be expanding out equally in all directions from the source. Unless we had thousands of years of warning, 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. If we're 100 light years from the source (say) and a mile of salt water doesn't attenuate the energy enough - then we'd need to be *way* more than 200 light years away if we could carry a quarter of a mile of water as a shield, 400 light years away if we had a sixteenth of a mile of water....for any reasonable amount of shielding, we need thousands of years notice of the problem happening.
In all likelyhood, we'd just sit back and let our great, great, great grandchildren deal with the problem.
We're basically doomed unless we have some kind of science-fiction technology.
www.sjbaker.org
A giant tinfoil hat is what's called for.
Boffoonery - downloadable Comedy Benefit for Bletchley Park
1) Send Bruce Willis and Ben Affleck to break the gamma ray in half...wait...
2) Make a gigantic lead planetary Dyson sphere
3) In the immortal words of David Levinson, "Uh, hide."
4) PANIC!!!
5) Seven words: Journey to the Center of the Earth.
6) Profit!!!
7) Seriously, did you just ask what we could do? Of course there's nothing we can do, you rhetorical-question-asking moron. We hope to Darwin that we can evolve.
8) Natalie Portman naked in hot grits. (If the world was about to end in a giant gamma ray bath, that is.)
p
In Korea, long hair is for old people!
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...
"And if we did, would there be any way to protect the planet?"
Uh, no? First, how would you propose we detect a gamma ray burst, which travels at the speed of light (of course), before it gets here? Second, you're talking about a pulse of energy strong enough to destroy life on a planetary scale from 6,000 light years away! How the hell are you going to protect against that?! Tin foil can't help you now!
On a side note, this was a plot device in a book by Stephen Baxter, although I can't remember the title. Every couple million years, two stars in the center part of the galaxy would collide, and knock all life in the galaxy back to single-stage or before; species would struggle back up the evolutionary ladder, and just as they achieved spaceflight, the next stars would collide. Great book-
As per your instructions, we've launched the probe.
Good luck sir, and Godspeed!
Given a number of confused responses to this, let's just remind everybody: it's not the gamma rays that kill (they would only get half of the globe anyway), it's the stripping away of the ozone layer followed by intense UV radiation. That's why it's a global effect.
While that would cause huge famines and disease and kill almost all humans, it is something that our species could survive given our technology.
For a limited time I am offering heavy gamma screen lotion. This specially formulated lotion can provide you with protection for up to 12 seconds. Our lotion has been formulated with special serpentin oils and thus is guarented to work. We offer full money back after neutron star event,if your not satisfied.
If the 6,000 LY limit is justifiable, I don't think it's quite as bad as you make out... at least not without some much more definitive research.
6,000 Light Years is practically next door on the galactic scale. It's certainly not infeasible (for someone qualified) to simply look at a survey of what's in our local space and determine immediately if we're at risk based on anything that looks unstable. (I'm not a professional astronomer, so someone's welcome to correct me if they know otherwise.)
The most obvious potential threat that's relatively close is probably Eta Carinae, which is about as massive as it's possible to get, and it's been hypothesised in the past that there's a small chance we might be at risk from a sudden gamma ray burst from it. But it's still about 8,000 light years away and there's still not enough known about it to have any accurate idea of when it's going to blow itself apart, either tommorrow or millions of years from now.
If there's still a reasonable chance that it could happen at some point in the future, this doesn't mean that there's any chance at all of it happening tommorrow. Stars orbit move a lot relative to each other sa they orbit the galactic centre. Our Sun does that in about 226 million years, but in the space of hundreds of thousands of years, galactic material barely moves relative to each other at all. It's feasible that at some time in the next few million years or more we will be close to something dangerous for some period of time. If we're not close enough to it now, though, the chance of that happening is still zero.
This is all dependent on that 6,000 Light Year limit being correct, of course. Clearly it's still all subject to change as we learn more about the Universe, which we still know next-to-nothing about. I don't think there's much point worrying about the great unknown, though, at least until we know enough to know that there's actually a risk. Otherwise it would just lead to paranoia.
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?
Short Answer: RTFA
Long Answer:
The Gamma rays would destroy the ozone on the unlucky side. Once the ozone redistbutes, you are down to 50% everywhere. That is, aparently, enough to kill plankton. Probably would kill land plants, too.
So, on the unlucky side everybody dies. On the lucky side, crops fail for several years. Very bad news, though I doubt it would actually exterminate the human race. Plants would still grow in UV filtered green houses.
A pre-print of the research article is available. The impression that I get is that they don't claim to really "prove" the idea, but rather pose it as a very interesting hypothesis which is compatible with the evidence and deserves further investigation. In particular, I think their claim is that gamma ray bursts can explain the evidence of rapid cooling from the extinction period. Of course, the popular press claims this tentative hypothesis like it was already a concrete fact, but that's what the press does.
Here's the basic info:
Title: Did a gamma-ray burst initiate the late Ordovician mass extinction?
Abstract: Gamma-ray bursts (hereafter GRB) produce a flux of radiation detectable across the observable Universe, and at least some of them are associated with galaxies. A GRB within our own Ggalaxy could do considerable damage to the Earth's biosphere; rate estimates suggest that a dangerously near GRB should occur on average two or more times per billion years. At least five times in the history of life, the Earth experienced mass extinctions that eliminated a large percentage of the biota. Many possible causes have been documented, and GRB may also have contributed. The late Ordovician mass extinction approximately 440 million years ago may be at least partly the result of a GRB. A special feature of GRB in terms of terrestrial effects is a nearly impulsive energy input of order 10 s. Due to expected severe depletion of the ozone layer, intense solar ultraviolet radiation would result from a nearby GRB, and some of the patterns of extinction and survivorship at this time may be attributable to elevated levels of UV radiation reaching the Earth. In addition a GRB could trigger the global cooling which occurs at the end of the Ordovician period that follows an interval of relatively warm climate. Intense rapid cooling and glaciation at that time, previously identified as the probable cause of this mass extinction, may have resulted from a GRB.
I thought we fell apart much more rapidly because of child-rearing.
You are confusing what you ought to do with what mathematically represents the general tendancies of your breeding behavior. In doing so, you deprive yourself of all the advantages of humanity. I also read the selfish gene. I was barely a highschooler when I read it: already interested in the field of genetics. At the time, it made a brilliant sort of sense. Our actions encaged by the selfish genes. How brilliant, how pure! When I grow up, I will have harems and seed sperm banks. My sweet sweet genes will survive! Twelve years and a lot of population genetics later I still remember that book quite clearly. I remember it because of how little since it makes in the face of real science. The first major crime committed by your arguement is that of heubris. Genetically, the death of the individual does not matter that much for a given gene pool. Your genes will continue as long as the group's genes continue: every gene in your genome will be represented. It makes heroism make a bit of sense. It opens us up for freedom to die. Quite liberating, actually. The second major crime espoused by your position is that of confusing mathematics with philosophy. Allow to to provide an example. When I was a young lad, after reading that foolish book, I was really concerned: I was brilliant, and it was my duty to insure my brilliant genes would pass on. I could insure this with my brilliance; with the harems and sperm banks previously mentioned. But would this be enough? Would I also have to go on semenary roadtrips across foreign lands, seeding the population like johnny appleseed? That's what Attila the Hun had to do, but I don't know if I could act like that. How would I be able to overcome my moral repugnance to the actions of the selfish genes? I was truly concerned that my moral sense was going to be a competitive disadvantage. Poisoned by memes! For surely nothing so disadvantageous as morality could have a genetic component? You have to forgive me for worrying about such silly things as selfish genes: I was extremely young and uneducated. I don't worry about that stuff any more. My genes aren't anthropomorphic things that define me and dictate my actions. They have brought me where I am, but then leave it up to me to decide what to do with it. Surely you can think of examples of choices that make sense for the individual but not for their genetic legacy? Surely you don't think that becasue genes are passed on, that that becomes more important than the choices you make? Monks make choices; they find those choices to be more important than passing on their legacy. Their genes are still circulating in the community of other humans; it is no loss to the pool. Their genes wouldn't care even if they did have a say. Evolutionary principles may tell us what happens, but they can never justify those choices. Your arguement could equally be used to rationalize male polygamy because of evolutionary tendancies. LEAVE DARWIN OUT OF IT. Mathematics has never been used to dictate morality.
Actually, there might be a way to get a little bit of warning, depending on the source of the gamma ray burst.
Photons (gamma rays) take a long time to get out of a star. But neutrinos, because of their physical properties, pass right through most of the star. Most nuclear reactions that generate photons also generate neutrinos. They're just very hard to detect (because of that same physical property).
Well, I'm working on a neutrino detector at the South Pole right now. http://icecube.wisc.edu/
It could, when it's complete, pinpoint the source of the neutrinos. Given the energy level of the neutrinos and the sudden, large burst of them, a whole lot of scientists are going to be woken up - and I mean that literally.
An earlier version of the project, AMANDA http://amanda.wisc.edu/, already has a supernova detector. It hasn't gone off yet, but when it does it will start a sequence of events that ultimately steers a lot of telescopes to point at that supernova.
1. 2.
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.
You cannot apply a technological solution to a sociological problem. (Edwards' Law)
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.
A polar bear is a cartesian bear after a coordinate transform.
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.
Sierra Tango Foxtrot Uniform
Dude, excellent band name!
In Soviet Rush, today's Tom Sawyer gets high on you.
Ozymandias
I met a traveler from an antique land
Who said: Two vast and trunkless legs of stone
Stand in the desert. Near them, on the sand,
Half sunk, a shattered visage lies, whose frown,
And wrinkled lip, and sneer of cold command,
Tell that its sculptor well those passions read,
Which yet survive, stamped on these lifeless things,
The hand that mocked them, and the heart that fed,
And on the pedestal these words appear:
"My name is Ozymandias, King of Kings:
Look upon my works, ye Mighty, and despair!"
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and level sands stretch far away.
Sound familiar?
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
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 :)
The gift of death metal does not smile on the good looking.
Laws of thermodynamics and entropic considerations ultimately dictate that organized (non-random) systems will eventually decay toward randomness.
However, the question with regard to rate is of the utmost importance in self-replicating systems. Bacteria in a sense do not die, in that they clone themselves (albeit with sometimes intermittant reproduction through genetic exchange with other bacteria) and hence in a sense are immortal (they make identical copies of themselves which persist more or less indefinitely).
Studies of the aging process (ie genes controling catabolism relative to anabolism) in eucaryotic organisms suggest that genetic systems have evolved genes that actually shorten life span. Hence, the question arises as to why, since one might initially assume that being able to live forever (like bacteria) would seem a more effective reproductive strategy.
It turns out that there appears to be selection for genes that produce shorter life spans in situations in which the presence of such genes increases the probability of survival of the offspring, even if their activity/presence takes place at the expense of the parent. It would seem that perpuation of self-replicating systems necessarily requires the need to take some risks to overcome the reality of dynamic environments. Ones current genetic makeup although nearly optimal (or more apply sufficiently near optimal) in the current environment may not be so in a future environment. Hence, a slightly different genetic makeup in ones offspring may be selected for in some future environment. Since prediction of exactly what the future environment might be is to some degree uncertain, most sexual organisms are capable of having more than one offspring, thereby increasing variety and hence the probability that at least some will be nearly optimally suited to survive.
Keep in mind, however, this is only an evolutionary strategy. While only those gene combinations that are successfull in reproducing will persist in subsequent generations, there is no guarantee that a particular gene combination will survive.
As for your arguments regarding "genes not grading anything in levels of mportance or having a perspective", this is really little more than a matter of semantics. The adult phenotype is nothing more than the product of its genes acting in an environment during its ontogeny. While it might seem to we are something more than our genes, at a molecular level there is nothing about us that is not the direct result of metabolic processes that occur (or occurred) as the direct result of the collective response/relative control of our genes to our environment. However, when you consider the shear number of different variatnts of tens of thousands of human genes and the incredible diversity of their responses to slightly different kinds of environments, the complexity is truely something to marvel at; so much so that it is hardly worth worrying about whether or not "something" (like some kind on mystical spiritual essesence or soul or other such unecessary nonsense) is missing.
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.
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!
Socialism: a lie told by totalitarians and believed by fools.