Killer Asteroids Are Good For Life 70
Hugh Pickens writes "NASA reports that according to a study by Rebecca Martin and Mario Livio asteroid collisions may have provided a boost to the birth and evolution of complex life on earth delivering water and organic compounds to the early Earth and accelerating the rate of biological evolution with occasional impacts to disrupt a planet's environment to the point where species must try new adaptation strategies. 'Too many asteroids, and you've got an unrelenting cosmic shooting gallery, raining fiery death from above,' writes Fraser Cain. 'Too few asteroids, and complex life might not get the raw material it needs to get rolling. Life never gets that opportunity to really shake things up and evolve into more complex forms.' Martin and Livio suggest that the location of an asteroid belt relative to a Jupiter-like planet is not an accident. The asteroid belt in our solar system, located between Mars and Jupiter, is a region of millions of space rocks that sits near the 'snow line,' which marks the border of a cold region where volatile material such as water ice are far enough from the sun to remain intact. 'To have such ideal conditions you need a giant planet like Jupiter that is just outside the asteroid belt [and] that migrated a little bit, but not through the belt,' Livio explains. 'If a large planet like Jupiter migrates through the belt, it would scatter the material. If, on the other hand, a large planet did not migrate at all, that, too, is not good because the asteroid belt would be too massive. There would be so much bombardment from asteroids that life may never evolve.'"
Re: (Score:1)
Nice, but speculation (Score:3)
This is nice, but it is entirely speculation. There really isn't enough data to make a conclusion.
Re:Nice, but speculation (Score:4, Interesting)
Of course it's speculation. How do you think you figure these things out? Time travel?
But it is potentially useful speculation. Instead of trying to find life on everything floating around random bits of fusion, look for specific parameters. Basically, one is attempting to Goldilocks the Drake Equation [wikipedia.org]. Since there appear to be lots of lots of bits of rock [discovery.com] orbiting random stars this can be a useful thing.
Re:Nice, but speculation (Score:4, Insightful)
But it is potentially useful speculation.
No, it's not terribly useful.
Instead of trying to find life on everything floating around random bits of fusion, look for specific parameters.
We can speculate that it takes a certain type of asteroid belt for a planet to have complex life, but since we don't have real evidence to prove that, it would be premature to filter our planet search based on a parameter of which we don't know the relevance. Especially since the only way to figure out whether it's relevant would be to look hard at all planets, in order to confirm or disprove the hypothesis.
Relying on a hypothesis that turned out not to be valid has already slowed down exoplanet searches once. Hot super-Jupiters could have been found by transit searches long ago, but nobody thought to devote resources to do the observation, since "of course" Jupiter-sized planets could only exist at high distances from their stars.
Re: (Score:3)
I think it's not even nice. It rests on the assumption that the earth needed some kind of external kickstarter to get life going which goes back to the conception that there was no way life could start from scratch so it had to come from elsewhere.
Let's take the idea seriously instead that the earth never needed the external kickstarter. Instead, and that any potential kickstarter would have been drowned out by what's already present.
Like comets delivering water to the sea.
Not as good for life as Alien spaceships... (Score:3)
Re: (Score:2)
Re: (Score:2)
...life forms that are non-organic. But after a few thousands of years processing data in their core CPUs, they decide they need to propagate across the Universe. The end solution is to create self-replicating nanites. The re-indroduction of the "cell" programed in DNA was the ultimate solution. What's old is now new again.
Hahaha! Can you bend a spoon?
Re: (Score:2)
Re: (Score:3)
Or to put it another way, not as good for intelligence. On the balance killer asteroids are pretty bad for life, but many of the life forms that survive must develop the ability to adapt rapidly to sudden and drastic environmental changes. The best way to do this is simply to get smarter. Now it may be a roulette wheel spanning hundreds of millions of years, but I think that eventually intelligence must emerge wherever there is a life in a relatively unstable location, since it is the ultimate evolutionary
Good for life (Score:5, Insightful)
But not as we know it, Jim
Great... (Score:1)
You just gave another idea to those mad scientists out here that want to create a master race. Instead of diseases they`ll use meteors!
Re: (Score:2)
You just gave another idea to those mad scientists out here that want to create a master race. Instead of diseases they`ll use meteors!
That is actually one of the possibilities in this game [boardgamegeek.com].
We don't need any more of those. (Score:4, Insightful)
It was perhaps great for life back in the old days a couple billion years ago. But it wouldn't be very good for us today. Can we not have any more mass extinction events, please?
Anyway, we're doing a pretty fair job of causing our own mass extinction. Nuclear war, tailored viruses, nano-machines run amock, artificial intelligence that wants us gone. Yup, lots of chances to do ourselves in and give the Earth a chance to start over.
Re:We don't need any more of those. (Score:4, Insightful)
Re: (Score:3)
When have any of those things you mentioned other than nuclear war ever come close to happening outside of a sci-fi novel? Why don't you concentrate on real problems.
... Said the dinosaur to the Ministry of Genetic Aeronautics.
Chickens Survive.
Re: (Score:3, Informative)
When have any of those things you mentioned other than nuclear war ever come close to happening outside of a sci-fi novel?
Tunguska - 1908 [wikipedia.org], and many other places [wikipedia.org].
Re: (Score:2)
Re:We don't need any more of those. (Score:4, Interesting)
When have any of those things you mentioned other than nuclear war ever come close to happening outside of a sci-fi novel?
It does not only happen in sci-fi novels, it also happens in sci-fi movies. Somehow because it happens in sci-fi, lots of people think it is likely to happen in the real world as well. Why are people so easy to manipulate, that just because you make fiction about something, lots of people will actually perceive it as a real threat?
There are real threats to mankind, but I don't think mankind is a threat to life in general. We are a threat to specific species, including ourselves. But though we may cause many species to go extinct, I don't believe we could wipe out life on Earth. But is earthlife going to survive when the Sun boils away our oceans millions of years from now? If mankind goes extinct, will there be enough time for a new civilisation to develop the capability to travel through space in the Earth's lifetime?
Re: (Score:3)
Nuclear war, tailored viruses, nano-machines run amock, artificial intelligence that wants us gone.
How about simple clearcutting and creating lots (and lots and lots) of smoke by burning stuff? I know, how mundane...
Fermi Paradox (Score:5, Interesting)
It is amazing how little we know about the universe. Not amazing in terms of "why don't we know this stuff", but amazing in terms of "there is so much to learn that it makes what we know seem infinitesimal."
Logic and what we know already point to a universe filled with intelligent life or at least life. Yet we seem so all alone. Are we the first? Are we in a universe filled with life and cannot detect it? Has this universe been abandoned by all the more advanced life forms and we're one of the few left? Are we in a zoo?
All of these questions, and we only have speculation for answers. I'd expect to have some answers to these question in the next generation or two. We're detecting planets at an accelerating rate and are getting to discover smaller planets now that Kepler has had enough time to get enough transits for the further away planets. Our detection of radio waves ability is improving and we now have better targets to try out.
While we may not have all the answers, I would expect by 2050 to know how common life is, but part of me wonders if we haven't detected intelligent life by then if we are not truly alone in this galaxy. I shudder to think that might be true, but it is a real possibility. We live in exciting times, and I thank those that have made missions like Kepler possible.
-- MyLongNickName
Re: (Score:2)
Re:Fermi Paradox (Score:4, Interesting)
It would be pretty amazing to me if ours were the only life in the cosmos. On the otherhand, at night I just look upwards and gaze at all of the Space there is yet to Conquer.
It's an almost insurmountable task -- One that will take the peaceful cooperation on a planet-wide scale to do, but I do believe it's possible for our race survive the hostilities the Universe throws at us. I nearly shed a tear each time I hear of NASA funding getting cut while trillions are wasted on pointless war efforts. If our primary goal as a species isn't getting some of our eggs out of this one basket, then we're surely doomed...
However you look at it, we've been dealt an amazing hand. When I hear folks talk about fixing problems at home first before venturing into space I think, "What a waste it would be to fold so soon."
Re: (Score:2)
Re: (Score:2)
I don't think we need to discover all planets to know how common planets are. If we do another couple of Keplers, looking at different areas of the sky, we can use statistics to give a very good estimate. That is doable this decade or next.
Once we have discovered a couple hundred viable planets, we do analysis of the atmosphere to look for signs of life. If life is as "easy" as seems to be the thought process today then we should find evidence to support. If a couple hundred planets turns up no evidence, th
Re: (Score:2)
Re: (Score:2)
Where are all the aliens? They're just like us - stuck in their gravity wells trying to find economic ways to travel vast distances quickly, as well as trying to replicate their planet's environment on a spaceship. We already know that life needs volatile chemicals to exist - otherwise space would be teeming with life.
Well, there's an awful lot of XeeLees out there, but they prefer living near galactic cores.
Re: (Score:3)
Re: (Score:2)
Logic and what we know already point to a universe filled with intelligent life or at least life. Yet we seem so all alone.
We, as a society, wouldn't be able to recognize intelligent life if it hit us in the head. Just look at the contempt most people show towards clearly sentient animals like elephants, dolphins and whales. (Some) scientists recognize their sentience, but almost nobody outside of their circles.
Hell, a few centuries ago, even black people from Africa were considered "without soul" (roughly translated as "without sentience"). I give us 0 chance of recognizing an alien life as intelligent.
Intelligent? Let me down
Are? (Score:2)
s/are/were/
Sounds good (Score:2)
Can we, within this theory, somehow equate human-induced ecological catastrophes to asteroid impacts?
Accident? (Score:2)
From TFS:
Martin and Livio suggest that the location of an asteroid belt relative to a Jupiter-like planet is not an accident. The
This seems to be a poor word choice. I think "coincidence" is far more appropriate choice to suggest a correlation. "Accident" seems to imply intent.
Great (Score:2)
This sounds exactly like the kind of spiel a supervillian would give, prior to actually becoming a supervillian. Once he's rejected by his alumni and alma mater, he'll go through the necessary drastic measures to make sure something like this happens, just to prove he's right.
Sure (Score:2)
Fermi Paradox explained (Score:2)
For my money, I'll bet life doesn't come out of the oceans (and develop fire and
100 percent of the time, everytime (Score:4, Insightful)
Basically, intelligent life can only evolve under circumstances identical to the way we evolved.
"100 percent of the cases where we know life evolved, these circumstances prevailed. Therefore..."
So - you're saying 60% of the time... (Score:2)
Re: (Score:2)
yes :)
Re: (Score:3)
Re: (Score:2)
Interesting theological plug. (Score:1)
If it's not an accident, then it's intentional. For it to be intentional, it must have been designed.
Sounds to me like they are trying to make a teleological argument for the existence of God.
Re: (Score:1)
The opposite of accidental isn't always 'intentional'. Sometimes it's 'consequential'
Re: (Score:2)
If it's not an accident, then it's intentional. For it to be intentional, it must have been designed.
Sounds to me like they are trying to make a teleological argument for the existence of God.
Yes, if the FSM hadn't moved Jupiter out a little, we might have evolved enough intelligence to reject silly arguments.
Supermassive Black Holes And Volcanos (Score:2)
Are also theorized as necessary for life on earth because all that loose hydrogen formed the Milky Way galaxy around Sagittarius A* and volcanos spread sulfur-based amino acids necessary for early life. Hurricanes, earthquakes, and tsunamis are probably also necessary for life in some way we don't yet understand.
In conclusion, if something is extremely detrimental to life, it's probably also necessary for it.
Re: (Score:2)
Hurricanes, earthquakes, and tsunamis are probably also necessary for life in some way we don't yet understand.
Real world is not such an intelligently designed well balanced video game. Well balanced games DO include weird stuff that is required specifically for a balance.
This appears to have no relationship with the real world.
Some things, just happen to suck. No hidden positive agenda was necessary for them to exist.
in some way we don't yet understand.
In conclusion,
Math teacher: Not amused. This is the classic dotcom logic in literary form: ...
1) something
2) something else
3)
4) success!
Re: (Score:2)
Killer asteroids are like political change. (Score:4, Insightful)
Killer asteroids are good to life that might emerge after the collision. But if you poll the existing life on the planet? meh! Its popularity is going to be very very bad.
Re:Killer asteroids are like political change. (Score:5, Funny)
Killer asteroids are good to life that might emerge after the collision. But if you poll the existing life on the planet? meh! Its popularity is going to be very very bad.
Polls showed that dinosaurs were strongly against the KT event, but more mammals showed up to vote. And the avian protest vote didn't help the dinos either.
Re: (Score:2)
Apophis 2029!
Eco-climatological change you can believe in!
Hand-waving and inconsistencies (Score:4, Interesting)
"Snowline"-based conjectures actually postulate that Jupiter was formed exactly because of its location on the snowline: since this snowline has to be a sharp boundary(1), a locally-enhanced density area, radially symmetric around the Sun(2), is created and collapses into a massive planet because it rapidly accretes material(3) from its neighborhood.
I have seen a lot of hand-waving used to fill in the gaps (note: "hand-waving": (idiomatic) Discussion or argumentation involving approximation, vagueness, educated guessing, or the attempt to explain or excuse vagaries) on where and when a gas giant actually forms in a snowline, and how exactly planets 'migrate'.
(1) sharp boundaries may not be as common as you think: there is only a handful of computer models that actually take into account the three-dimensional structure of the accretion disk (proto-planetary disk, a very computationally expensive problem) and lots of physics are lost in 2D simplifications.
(3) Fairly recent observations have shown that complex organic molecules are present in Giant Molecular Cloud [wikipedia.org] structures, long preceding the formation of any star or planet. The mechanism of their creation and their distribution is mostly unknown, and an active area of research, as of course is the formation of planetary systems. Hand-waving has not produced any robust results as of yet. Computer modeling, on the other hand, looks more promising.
Re: (Score:2)
Re: (Score:3)
Doesn't common sense just confirm the sun has to be similar to what it is today?
No: as matter accretes to the centre of the disk, the central object becomes more and more massive, and it radiates energy out via what is called the Kelvin-Helmholtz mechanism [wikipedia.org]. To make matters even more complicated, an astrophysical non-equillibrium jet is formed during the accretion process through which the disk parts energy and angular momentum. So the central object only becomes Sun-like in its properties when this jet dissipates, and its mass is enough to start a thermo-nuclear, pressure-sustained fu
Life would therefore be common... (Score:2)
Hmm... (Score:2)
Good for life after transiently being really, *really* bad....
Biggest threat to intelligent life (Score:2)
They're good for life... (Score:2)
Maybe in the abstract ... (Score:2)
These things may be good in the abstract, in that Life can get nudged along by them.
But once life has formed, it's not so good for it .. just ask the dinosaurs. ;-)
My name is Arnold Schwarzenegger and lemme tell ya (Score:1)
Girly Man: A Steroid is bad!