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Scientists Study Trajectories of Life-Bearing Earth Meteorites

samzenpus posted more than 2 years ago | from the we-come-from-earth dept.

Earth 199

Hugh Pickens writes "About 65 million years ago, Earth was struck by an asteroid some 10 km in diameter with a mass of well over a trillion tonnes that created megatsunamis, global wildfires ignited by giant clouds of superheated ash, and the mass extinction of land-based life on Earth. Now astrobiologists have begun to study a less well known consequence: the ejection of billions of tons of life-bearing rocks and water into space that has made its way not just to other planets but other solar systems as well. Calculations by Tetsuya Hara and his colleagues at Kyoto Sangyo University in Japan show that a surprisingly large amount of life-bearing material ended up not on the Moon and Mars, as might be expected, but the Jovian moon Europa and the Saturnian moon Enceladus also received tons of life-bearing rock from earth. Even more amazingly, calculations suggest that most Earth ejecta ended up in interstellar space and some has probably already arrived at Earth-like exoplanets orbiting other stars. Hara estimates that about a thousand Earth-rocks from this event would have made the trip to Gliese 581, a red dwarf some 20 light years away that is thought to have a super-Earth orbiting at the edge of the habitable zone, taking about a million years to reach its destination. Of course, nobody knows if microbes can survive that kind of journey or even the shorter trips to Europa and Enceladus. But Hara says that if microbes can survive that kind of journey, they ought to flourish on a super-Earth in the habitable zone (PDF). 'If we consider the possibility that the fragmented ejecta (smaller than 1cm) are accreted to comets and other icy bodies, then buried fertile material could make the interstellar journey throughout the Galaxy,' writes Hara. 'Under these circumstances fragments could continue the interstellar journey and Earth origin meteorites could be transferred to Gl 581 system. If we take it as viable, we should consider the panspermia theories more seriously.'"

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Don't you mean... (-1, Flamebait)

Anonymous Coward | more than 2 years ago | (#39656083)

Godeorites? They were created 6000 years ago along with the Dinosaurs.

Panspermia (5, Insightful)

The Evil Atheist (2484676) | more than 2 years ago | (#39656131)

If we take it is viable, we should consider the panspermia theories more seriously.

Only as a possible answer to the origin of Earth's life. It still doesn't answer the origin of life itself, wherever it may have started.

Re:Panspermia (5, Insightful)

olsmeister (1488789) | more than 2 years ago | (#39656239)

No, but it could answer the question of how life managed to arise here on earth in a relatively short period of time, and would also exponentially expand the potential area we consider when we think about places that could have been suitable, both chemically and environmentally.

Re:Panspermia (2)

kanweg (771128) | more than 2 years ago | (#39656707)

When you throw a dice, your first throw may be a six. Why are you trying to do statistics with a single event?

Bert

Re:Panspermia (2)

SQLGuru (980662) | more than 2 years ago | (#39656933)

When you throw a dice, your first throw may be a six. Why are you trying to do statistics with a single event?

"God does not play dice with the universe."

Re:Panspermia (0)

Anonymous Coward | more than 2 years ago | (#39656985)

When you throw a dice, your first throw may be a six. Why are you trying to do statistics with a single event?

"God does not play dice with the universe."

Well not since his GMPC got one-shotted by the Romans anyway.

Re:Panspermia (1)

CSMoran (1577071) | more than 2 years ago | (#39657173)

When you throw a dice, your first throw may be a six. Why are you trying to do statistics with a single event?

Bert

Not statistics. Educated guesses. With just one throw available to reason from, the educated guess for the next throw is another six.

Re:Panspermia (0, Funny)

Anonymous Coward | more than 2 years ago | (#39656255)

I think God did it as stated in the Bible, but since time is relative to Gods perspective and it didn't say there were NO dinosaurs. I guess he just threw a rock to see what would happen at some point. Probably wasn't necessary to mans salvation to give all the details.
Makes more sense than some hokum about panspermia. If a rock hit, no one knew which way the ejecta blew and with such great distances and so many degrees of freedom to take, it is sooooo doubtful it made it anywhere immediately useful to seed anything anywhere or even travelled to some distant system and then land somewhere useful there.
Must be kinda like throwing a handful of marbles over the edge of the Grand Canyon and hoping one lands in someones water-glass somewhere below, maybe.

Re:Panspermia (1)

Anonymous Coward | more than 2 years ago | (#39656465)

No way was God an onanist. That's a sin you know: "tossing rocks" and "ejecta-ing" your "panspermia" all over the ground.

Re:Panspermia (4, Interesting)

Migraineman (632203) | more than 2 years ago | (#39656737)

I guess he just threw a rock to see what would happen at some point.

So your version of God isn't all-knowing and all-powerful? I'm not buying that a God who is capable of creating billions of planets, stars, and systems wouldn't have a firm grasp on probability and interstellar trajectories. Maybe we should consider that your God is bored (he does control everything, right?) and has set up the universe as a giant Rube Goldberg machine for His entertainment. He would have to accede to non-interference for the exercise to have any value.

Re:Panspermia (0)

Ashenkase (2008188) | more than 2 years ago | (#39656833)

I think God did it as stated in the Bible

If its stated in a book of fiction then it HAS to be true.

Excuse me while I go out back to feed my Unicorn.

Re:Panspermia (5, Interesting)

fatphil (181876) | more than 2 years ago | (#39656261)

I've seen arguments on a scientific mailing list in the last few days that this paper is based on false assumptions. It has assumed (too high) values for masses based on (too low) values for velocities based on the assuption that the meteorites are aiming at earth under its gravity, rather than aiming for the sun under its gravity and accidentally hitting earth on its way towards the sun.

If you change the masses downwards to what they should be, then the chance of them getting through an atmosphere without breaking/burning up and denaturing all its alleged payload become minuscule.

Re:Panspermia (2)

jellomizer (103300) | more than 2 years ago | (#39656313)

God? (Ducks!)

I still follow the premise that Life originated on earth. As a random chemical reaction, that created simple DNA strains that that happened in an area where the environment stayed constant enough for those chemical reactions to persist but changing enough to allow the strain to change over time. The Chemical Reaction that didn't break down allowed for more chemicals to connect to the DNA strand and multiply.

Re:Panspermia (3, Insightful)

ArcherB (796902) | more than 2 years ago | (#39656501)

God? (Ducks!)

I still follow the premise that Life originated on earth. As a random chemical reaction, that created simple DNA strains that that happened in an area where the environment stayed constant enough for those chemical reactions to persist but changing enough to allow the strain to change over time. The Chemical Reaction that didn't break down allowed for more chemicals to connect to the DNA strand and multiply.

While thinking about it, the environment would not necessarily need to change to force the DNA to change (evolve). All the "environment" needs is to be stable enough to foster replication. The edges of such an area would provide the change in conditions needed for evolution to take hold. The bonds that were able to multiply at the edges and beyond did so. Those that were not able to didn't.

An example would be ocean vents. This environment is rather stable and fosters life within it. Along the edges, where the conditions are not as favorable to the original life forms, most those that are venturing out will die. Those that don't die continue to reproduce, each surviving generation better able to survive further away from the vents until the need for the vents completely disappears.

Just my $0.02 and I'm not a biologist. But I have stayed in a Holiday Inn and the concepts are not that hard to grasp.

Re:Panspermia (3, Insightful)

mcgrew (92797) | more than 2 years ago | (#39656609)

From what I've read (which was a LONG time ago so further discoveries and theories may have developed), Earth had little or no oxygen when life developed, and the oxygen would have been a poisonous byproduct, like methane is to today's life.

So life itself would have changed the environment, of course along with other such variables as volcanos, continental drifting, and meteors.

Re:Panspermia (1)

Intrepid imaginaut (1970940) | more than 2 years ago | (#39657823)

All the "environment" needs is to be stable enough to foster replication.

Its the bit between "dumb chemicals" and "things actually replicating" where we're a bit wobbly. If a stable environment were all it took we could have recreated the process many times.

Re:Panspermia (1)

Chris Burke (6130) | more than 2 years ago | (#39657695)

God? (Ducks!)

Indeed -- not God, but Ducks! Some might say they're one in the same (especially the ducks). And given ducks' well-known sexual proclivities, a theory of panspermia where basically every object in the galactic vicinity, even those with no chance of the payload taking root, being "inseminated", makes a lot of sense.

Re:Panspermia (5, Informative)

socialleech (1696888) | more than 2 years ago | (#39656383)

You should read about the Miller-Urey experiment [wikipedia.org] .

For those to lazy to read about it, scientists have created all of the amino acids required by life, using nothing but inorganic compounds, by recreating the atmospheric conditions of early Earth.

Life may or may not have originated on Earth, but we tested it and found that it could have. If it could have been created here, using nothing but the things that the universe placed here, why couldn't it have also developed else where? Are we the seeding planet of the galaxy/universe? Were we seeded? Or is life just incredibly common?

Re:Panspermia (2, Informative)

Anonymous Coward | more than 2 years ago | (#39656915)

You're not still dragging out that tired old experiment, are you? Have you figured out how many orders of magnitude (both in terms of probability and complexity) bare amino acids are away from the simplest self-replicating thing we have found on earth so far? You'll need a lot more experimental evidence than just Miller-Urey to bridge the gap between inorganic compounds and life.

(Yes, there are experiments that show self-replication of specially-designed ad hoc molecules, but the experimenters have to provide all the raw materials in just the right amounts for those experiments to work. Not exactly realistic pre-biotic conditions.)

Re:Panspermia (3, Insightful)

paleo2002 (1079697) | more than 2 years ago | (#39657407)

When comparing panspermia to a terrestrial origin for life people seem not to fully comprehend one important factor: time.

It began raining on the Earth about 4-4.4 billion years ago, meaning surface temperatures and atmospheric conditions were stable enough for the oceans to accumulate. Some of the earliest evidence of biochemical alteration of the atmosphere (banded iron formations) first appear about 3.7 billion years ago. That's over 500 million years for naturally occurring amino acids to jump to self-replication and then to simple prokaryotes. Now, think about the rate at which microorganisms reproduce. 500Ma is about as much time as its taken for life to jump from single-celled forms to modern vertebrates, etc.

Panspermia includes too many unknown and slim chances. And, as mentioned elsewhere in these posts, where are these life-seeding bolides coming from?

Re:Panspermia (1)

symbolset (646467) | more than 2 years ago | (#39657585)

where are these life-seeding bolides coming from?

Did you know that all of the elements on Earth heavier than iron were once inside a star? It's true - and not our star, either.

Re:Panspermia (1)

CSMoran (1577071) | more than 2 years ago | (#39657795)

where are these life-seeding bolides coming from?

Did you know that all of the elements on Earth heavier than iron were once inside a star? It's true - and not our star, either.

Except for the ones we created by nuclear fusion.

Re:Panspermia (1)

ColdWetDog (752185) | more than 2 years ago | (#39657629)

Amino acids don't self replicate. That's what DNA (or RNA) is for. However, your primary point is still valid. Time allows nature to futz around until something works. 500 million years is a long time. A very long time.

Re:Panspermia (1)

Electricity Likes Me (1098643) | more than 2 years ago | (#39658045)

Also any chemist knows that you always get a little of an unlikely reaction product if your original volume is big enough, or you mix things for long enough. You only need to make a self-replicator (or just a vaguely catalytic) product once.

Re:Panspermia (1)

geekoid (135745) | more than 2 years ago | (#39657925)

Other planets.

You can have both.
Hell, Human beings could be wiped out by a giant piece of rock from a destroy planed, and organic compound on that rock could eventually become the new life forms.

Re:Panspermia (1)

Chris Burke (6130) | more than 2 years ago | (#39657659)

Of course Miller-Urey is pretty irrelevant now that we've found amino acids floating in clouds in space. They're everywhere.

Anyway, so we're accepting that spontaneous assembly of self-replicating molecules is possible in principle, but appealing to the low probability of the right conditions appearing. Well, billions of years of constant change due to geologic activity and countless deep-ocean vents of varying compositions, plus the fact that we're here, suggests that while the probability may be low, the expected value of the experiment over that time frame is not so low.

Re:Panspermia (1)

geekoid (135745) | more than 2 years ago | (#39657937)

No it isn't. It shows that amino acids can come from inorganic compounds. Being on Earth isn't needed.

Re:Panspermia (1)

MozeeToby (1163751) | more than 2 years ago | (#39657915)

How many orders of magnitude? Ok, let's say that the odds of those amino acids forming a self replicating 'thing' are 1000000000000 less likely than the formation of the amino acids themselves. It took Miller-Urem 1 gallon of water and 1 week of time to produce virtual every amino acid required for life. Now instead of a gallon, you have the entire surface area of the Earth's oceans at the time. And instead of a week you have millions, if necessary billions of years. Every time someone talks about how bad the odds are for evolution or abiogenesis, I have to wonder if they are really thinking about what they're saying. Yes, the odds are going to be long. Very, very long. But so is the scale, both in size and time.

Re:Panspermia (0)

Anonymous Coward | more than 2 years ago | (#39657277)

The best part about that experiment is how he traps the amino acids because he knew they'd be destroyed if they were to continue through the cycle. I think atmospheric conditions of early Earth were not so kind as to trap amino acids simply because they would have just been destroyed right away.

Re:Panspermia (0)

Anonymous Coward | more than 2 years ago | (#39657611)

Yes but they haven't created the life itself.

Build a rocket is one thing. Landing safely on the Moon is another. Getting back alive... even harder still.

Re:Panspermia (1)

Barbara, not Barbie (721478) | more than 2 years ago | (#39658017)

If we take it is viable, we should consider the panspermia theories more seriously.

Only as a possible answer to the origin of Earth's life. It still doesn't answer the origin of life itself, wherever it may have started.

So you mean mom was right - you are evil alien spawn?

Re:Panspermia (1)

tinkerton (199273) | more than 2 years ago | (#39658075)

I'll offer a view that goes the other way round, that of the irrelevance of panspermia. Life originated on earth because under the right conditions that is inevitable. Incoming meteorites with life or predecessors of life wouldn't have made any difference. Life on other planets is hard. Incoming seeds originating from earth wouldn't make any difference.

If you look at the origins of panspermia theories however, they're of the silly kind: "life is very difficult to start so it must have come from elsewhere".

and all galactic life will be like star trek (1)

alen (225700) | more than 2 years ago | (#39656139)

humanoids walking on two feet with funny heads

Re:and all galactic life will be like star trek (1)

geekoid (135745) | more than 2 years ago | (#39657951)

There are a lot of advantages to being bipedal. On planets with land.

that's depressing (5, Funny)

circletimessquare (444983) | more than 2 years ago | (#39656149)

so the culmination of mankind's civilization, scientific efforts, and technological achievements, is to go to some exoplanet, only to find some foot fungus some dinosaur had long before mankind ever appeared?

Re:that's depressing (1)

Anonymous Coward | more than 2 years ago | (#39656479)

It could be worse, the dinosaur foot fungus may have evolved further than us ...
well for most people it would be worse since they don't see a need to improve on current state of affairs,
I for one welcome out dinosaur foot fungus overlords!

Re:that's depressing (0, Funny)

Anonymous Coward | more than 2 years ago | (#39657453)

so the culmination of mankind's civilization, scientific efforts, and technological achievements, is to go to some exoplanet, only to find some foot fungus some dinosaur had long before mankind ever appeared?

... where it then evolved further and began teaching creationism in classrooms.

Place Bets Here (2, Interesting)

flyneye (84093) | more than 2 years ago | (#39656175)

Hmmm, made it to other Earth-like planets instead of randomly catching a closer strong gravitational field or drifting randomly into nothingness.
Even making Europa would be kind of like hitting a cockroach with a needle from across a football stadium.
Oh to be the house, if this scientist ever landed in Vegas with a wallet-load... Sounds like someone needs to re-fill the ol' grant jar.

Re:Place Bets Here (2)

19thNervousBreakdown (768619) | more than 2 years ago | (#39656197)

Apparently you've forgotten about gravity.

Re:Place Bets Here (4, Insightful)

jochem_m (1718280) | more than 2 years ago | (#39656249)

and the fact that it's more like hitting any of a dozen cockroaches with a million needles...

Re:Place Bets Here (1)

flyneye (84093) | more than 2 years ago | (#39657711)

To add to my Vegas theme, consider the planets are moving like a roulette wheel. Further consider that gravity could also act as a slingshot rather than a mitt, dependent on distance from the modifying source it approaches. The numbers of the odds just roll like cherries, bells and bars on a slot machine, the more criteria you add.

Re:Place Bets Here (1)

Anonymous Coward | more than 2 years ago | (#39656267)

Yeah, Europa is orbiting something with lots and lots of gravity.

Re:Place Bets Here (2)

flyneye (84093) | more than 2 years ago | (#39657601)

Which gravity? The Suns? Are you assuming the ejecta came out in a general direction available to magically put it under the weak gravitational field of planets and moons so distant it would be like trying to get a BB to stick to a magnet by throwing it across the stadium? Did you not take into account how many directions are available that do not line up with the motions of our Suns hub of planets and asteroids? If it went in an upwards direction relative to our position around the sun, even nearby gravity would steer it only a bit as it flew at amazing speeds through the vacuum to nowhere in particular. Reach a distant system from there? Did you win the Mega-millions jackpot? No? Probably just some organic space crap floating somewhere to this day.
It's probably nicer to think of it in the role that this story imagines it, just not very likely. I just can't make myself see it. I'll see it when I believe it or visa versa, whatever.

You are exceptional (5, Insightful)

exploder (196936) | more than 2 years ago | (#39656745)

Astounding! With just a few minutes of thought and your superior intuition, you've dismissed the result of careful calculation and decades of training on the part of this group of scientists. Imagine what a genius of your magnitude could accomplish from within the scientific system...it truly staggers my humble intellect! But I'm sure you're working on much more important things.

Re:You are exceptional (1)

flyneye (84093) | more than 2 years ago | (#39657811)

Noticing that the king wears no clothes is one thing, and not appropriate, but yes, I question the absence of his codpiece.
Now if you have any information about the physical absence of his genetalic cover, I would appreciate some of this insight your fanboys have endowed you with.

Re:You are exceptional (1)

ceoyoyo (59147) | more than 2 years ago | (#39657989)

You're just a trash tabloid staff editorialist unless you actually read the paper and comment intelligently on their methods. I suppose you might get some play on the National Enquirer... I mean Slashdot, but that doesn't make you clever or insightful.

Re:Place Bets Here (0)

Anonymous Coward | more than 2 years ago | (#39656751)

hitting a cockroach with a needle from across a football stadium.

Tebow could do it! Oh wait. I mean he could hit a needle with a football stadium from across a cockroach (as long as the needle didn't move.)

Re:Place Bets Here (1)

foamrat (1866110) | more than 2 years ago | (#39657257)

Now that's funny, I don't care who you are.

Re:Place Bets Here (2)

Chris Burke (6130) | more than 2 years ago | (#39656895)

Even making Europa would be kind of like hitting a cockroach with a needle from across a football stadium.

True. Now explode a pile of trillions of needles and see if any one of them hit the cockroach.

Oh to be the house, if this scientist ever landed in Vegas with a wallet-load...

If the bet was that any of the visitors to Vegas would win the slot machine jackpot, the house might not be as willing to make the wager as you.

Of course they'd only make that decision after doing what this scientist did, and actually calculating the expected pay-out. Estimating probabilities by gut feel isn't going to make you a winner in Vegas, even if you are the house.

Re:Place Bets Here (1)

flyneye (84093) | more than 2 years ago | (#39657963)

I dunno about a trillion. Let's add that to the mix though.
If it were that means the ejecta really splattered like Gallaghers melon in a lot of directions, but also that smaller amounts went with each "packet". perhaps a few "needles"were icy raindrops and hit. Then you face odds of survival. How's earthlife going to do as an ice chunk of earth water or frozen mudball on the surface of an icy moon? Of course the odds of these raindrops (which are still dispersing further from each other, the further they travel in this splatter scenario. This makes the odds of further planets getting a survivable amount of "geo- sperm" less than Europas.
        Even then we must consider the many directions it could go. We're not too far from the edge of the Milky- Way, did it go toward or away? Even up or down from that perspective are options. Then let's not forget gravity. This stuff could be flying around space in chunks or pieces to this day and not land anywhere.

Martin Lo's low energy trajectories (4, Informative)

mattr (78516) | more than 2 years ago | (#39657255)

Actually Martin Lo discovered low energy gravitational paths or "superhighways" that would allow objects like space probes and maybe rocks to travel all around the solar system without power. These calculations were used in the Genesis probe NASA project IIRC.
http://en.wikipedia.org/wiki/Interplanetary_Transport_Network [wikipedia.org]
http://genesismission.jpl.nasa.gov/gm2/team/people/lo/interview1.htm [nasa.gov]

Re:Martin Lo's low energy trajectories (1)

flyneye (84093) | more than 2 years ago | (#39658013)

Now that's a consideration too, another spin of the wheel in space-Vegas.
Might an x % or even all of this be stuck on some pan-galactic Nascar track to nowhere?
I wish I could get all you guys to see each others posts and ideas to add to the odds, it would make this thread a blast!

Re:Martin Lo's low energy trajectories (1)

flyneye (84093) | more than 2 years ago | (#39658109)

And yes that increases the odds of it hitting something in our system, acknowledged. But the value of icy chunks landing on an icy surface with our homegrown life starts then being able to evolve usefully in this amount of time is in question. The Mars thing would be cool and it would give some "Enquirer prestige " to some Russian Scientist rumoured to have seen a "scorpion" like thingamadoo on a Venus pic. (lol, maybe that was the Enquirer someone told me about)

Re:Place Bets Here (0)

Anonymous Coward | more than 2 years ago | (#39657661)

No doubt your assesment of the odds is correct.... ...which by no means disproves the theory one iota.

Sub 1cm Ejecta (4, Interesting)

RivenAleem (1590553) | more than 2 years ago | (#39656177)

How do objects this size survive the trip through the destination planet's atmosphere?

Re:Sub 1cm Ejecta (1)

dryriver (1010635) | more than 2 years ago | (#39656223)

The probably answer is that they don't. If things falling into earth's atmosphere (e.g. small meteorites) burn up nearly completely during the trip, then the same should happen to those 1cm Ejecta falling into another planet's atmosphere, no?

Re:Sub 1cm Ejecta (1)

ciderbrew (1860166) | more than 2 years ago | (#39656293)

I think you have to go into the billion billion range of odds and think up the scenario that allows that 1cm bit to land with its cargo intact. It landed on a still forming plant that didn't have much atmosphere at the time? Is a billion billion enough for this?

Re:Sub 1cm Ejecta (1)

Ashenkase (2008188) | more than 2 years ago | (#39656627)

Your assuming the destination exo-planet has a similar atmosphere to earth. The density of Earth's atmosphere has changed over the course of 4 billion years mainly due to the presence of life. If an exo-planet has little to no life on it pre-ejecta impact then its possible its atmosphere is extremely thin which would allow the ejecta to "mostly" survive its fall down the gravity well.

Re:Sub 1cm Ejecta (1)

geekoid (135745) | more than 2 years ago | (#39657979)

depends on the atmosphere and speed, but probably. Of course, 'burning up' doesn't mean the mass goes away, just changes.

Re:Sub 1cm Ejecta (0)

Anonymous Coward | more than 2 years ago | (#39656243)

How do objects this size survive the trip through the destination planet's atmosphere?

If we consider the possibility that the fragmented ejecta (smaller than 1cm) are accreted to comets and other icy bodies

They're banking on them not being sub 1cm ejecta by the time they arrive at the destination planet. the question then is what acctually are the odds of them coalescing like that?

Re:Sub 1cm Ejecta (1)

RivenAleem (1590553) | more than 2 years ago | (#39656469)

Well, I also considered that, but what happens when a 1cm object is attached to a bigger one, which then enters another planet's atmosphere? It would be the first thing that ablates off, or would be near the surface when it hits the ground at supersonic speeds. Either way, living things on small things have no realistic chance of making it down to the surface alive.

Re:Sub 1cm Ejecta (1)

Ashenkase (2008188) | more than 2 years ago | (#39656767)

It would be the first thing that ablates off, or would be near the surface when it hits the ground at supersonic speeds.

Meteorites large enough to make it through earth's atmosphere hit the earth at sub-sonic speeds.

Even an object the size of an interplanetary probe hit the earth at sub-sonic speeds. Take for example the Genesis [wikipedia.org] probe, it was travelling at 24,706 mph when it first encountered the earth's atmosphere, but when it hit the ground it was only travelling 193 mph.

It is quite plausible that microbes or some other form of life BURIED in a meteorite could survive the plunge down an exo-planets gravity well and atmosphere.

You are also assuming that the exo-planets atmosphere is the same density as Earth's. Again it is very possible that the exo-planets atmosphere is very thin compared with Earth's meaning small objects have an even better chance to survive the plunge.

Re:Sub 1cm Ejecta (1)

ceoyoyo (59147) | more than 2 years ago | (#39658033)

Some of them are big enough, others hitch a ride on comets or asteroids.

There are pieces of Mars littering Earth. It happens.

Galactica (2)

SJHillman (1966756) | more than 2 years ago | (#39656183)

There are those who believe that life out there began here
Flung far across the universe, before there were tribes of humans...

is this how life started here too? (0)

Anonymous Coward | more than 2 years ago | (#39656199)

The next question has to be, was the Earth injected with life too? Is this how life started on our planet?

Re:is this how life started here too? (1)

Anonymous Coward | more than 2 years ago | (#39656449)

This is not the "next" question, you're just repeating the last point made in the summary.

Worth a read, but ... (5, Interesting)

Trapezium Artist (919330) | more than 2 years ago | (#39656205)

I've made a quick scan of the underlying academic article by Hara et al., along with one of my colleagues in a meeting here, who is closely involved in the issue of planetary protection (i.e. making sure that our spacecraft don't "pollute" the solar system bodies they fly to and land on).

Of course, this is a known issue in general: after all, there are meteorites on Earth which we know came from Mars, so the converse is obviously possible. But extending this to moons of Jupiter, Kuiper Belt objects, and even exoplanetary systems, and finding that a significant number of Earth rocks may have been dumped there is interesting. So, the article is worth a more careful read.

However, my antennae were sent into a state of high agitation when I saw that the article has been posted on the arXiV following its having been accepted to the infamous Journal of Cosmology. We've discussed that here before: I invite you to view the journal website (easily found by googling) and decide for yourselves how reputable it is.

Which raises the question of why Hara et al. chose to publish there. That I can't answer, obviously, but will keep it firmly in mind as I read the paper in more detail.

Re:Worth a read, but ... (1)

CrimsonAvenger (580665) | more than 2 years ago | (#39656761)

Which raises the question of why Hara et al. chose to publish there. That I can't answer, obviously, but will keep it firmly in mind as I read the paper in more detail.

Because it's rather long on speculation and short on facts?

And because there's no way to test any of this for a very long time to come?

Re:Worth a read, but ... (1)

Trapezium Artist (919330) | more than 2 years ago | (#39657001)

Well, in principle the paper is a fairly simple series of mathematical equations which you could actually work out on the back of an envelope. The devil though is in the details, namely the numerical parameters input to those equations. While many of those are straightforward and well-known, some may enter that category of WAGs (wild-assed guesses), and it's quite possible that the equations are particularly sensitive to (some of) those. That's why it's worth reading, to try and figure out where the issues may be.

As for the testability side, you're right, of course: very hard. But again, since we know of Martian rocks having made it to Earth via this mechanism, we can at least start to use some hard numbers based on that to try and constrain the likelihood of the Earth rocks having made it to other planets / moons.

Re:Worth a read, but ... (1)

Confusedent (1913038) | more than 2 years ago | (#39656847)

Oh seriously, those people? They're always pushing panspermia stuff. Like that whole "discovery of microscopic alien life" thing last March [wikipedia.org] . From what I remember of that whole thing, the journal itself isn't to be taken seriously. Their research on the meteorites might be good, but the fact it appeared in JoC doesn't make me hopeful.

Re:Worth a read, but ... (1)

garyoa1 (2067072) | more than 2 years ago | (#39657415)

"there are meteorites on Earth which we know came from Mars"

This always annoyed me. While we can assume they did... why do we assume this? We were never there. Just because some tests show it's features are the same doesn't mean it "absolutely, positively" came from there. Claiming we "know" they came from Mars is a pretty big stretch IMHO.

Re:Worth a read, but ... (0)

Anonymous Coward | more than 2 years ago | (#39657783)

Well, the poster claiming we "KNOW" they came from MArs is a bit strong. Some smart folks really really THINK they came from Mars, and they have some really strong arguments (and data) to support that claim.

But there is always the possibility that they are wrong.

In that vein they are looking for rocks from Earth on Mars, also they are looking for regular ol' meteorites (which I think have been found by the rovers).

the dark side of the moon IS A TRAP! (-1)

Anonymous Coward | more than 2 years ago | (#39656225)

"I mean the people when you look at them or talk to them it's like there clueless and their mind is off in outer space.And even a simple conversation seems like something their not capable of,whats up with them."

I swear there is another, even larger thread about this same issue. Maybe more people are just waking up to this. When you're in a place where people are waiting or in transit in large groups, a Subway, a Bus station, etc. in checkout lines in stores, at amusement parks in long lines, etc.

(I am not promoting or suggesting you or anyone watch one or any of the following films. I haven't since I've awoken and I intend to avoid them from now on):

Films that have always bothered me when considering what you've said, in the real world:

* They Live: but what if he was going *too* far and these *aliens* were just possessing the people and he saw the evil which was front and center while the human was "asleep" (Matrix possible connection) in the background of the mind?

* Truman Show: if not "one" individual, what of "millions" all duped by another race?

* Dark City: what if not only the "dead" were/are being used as vessels, but living ones
as well? (remember "Dax" from ST:DS9? and her "parasite" like being inside her?)
Something interesting if you should ever watch Dark City, potential spoiler,
one guy who "woke up" was concerned about "them" getting to him, so he found
a way out, and he jumped in front of a train to his death..
if you go frame by frame around the time or after he jumps in front of the train,
or press pause exactly at the right moment (it's difficult to spot if you use
pause) there is a poster on the wall, where one normally wouldn't be in real
life, and it mentions HELL, I forget what it says exactly, but HELL is mentioned
on the poster. It's been a long time since I've sat down with Dark City, and
honestly I won't again, it's too jarring to the mind once you've explored all of
this Illuminati crap.

* Matrix: In my opinion the movie is a lie, IMOthe red pill symbolises the opposite, being
pushed into a frame of mind or (sub)reality in which you are a puppet and controlled.
vs. "awakening" to truth, instead you are "deceived" through lies. Symbolism of
the creature taken from Neo could be related to a soul or more likely a protective
(holy) spirit, extracted by Satanists. The whole "Matrix" world, when viewed in
reverse (no, I don't mean watching it from ending to beginning) and perverted *for*
Satanist world-view/goals is eye opening, the same with Dark City. This movie only
bothers me, not for the fake/real awakening/reality concepts but in that I feel
the whole movie, IMO is a lie and the real meaning is perverted, kind of like..

* Fight Club: On many levels this movie bothers me, but I see the dark female character in the
movie as an evil angel which is involved in the split of the two identities of
the one leading role. In the same way I perceive her role in the film I see the
same, or feel the same vibe for the role of the female evil creature in the movie..

* The Ninth Gate: both the "odd" female role in this and in Fight Club shout out to me in
that they are both playing a similar or the same role. Please don't watch
this movie, I'm sorry I ever did.

#
This one, not so much as the method of alien attack as for how it sometimes "feels" for the person played by NK, in public once they've awoken to the aliens around them and how they act, or rather what actions the aliens DON'T display:

* The Invasion (I) (2007) | Nicole Kidman in lead role
http://www.imdb.com/title/tt0427392/ [imdb.com]

Tucker: When you wake up, you'll feel exactly the same. (possible tie-in to the movie, "Dark City")

"As a Washington psychiatrist unearths the origin of an alien epidemic, she also discovers her son might be the only way it can be stopped."

Yorish: I say that civilization is an illusion, a game of pretend. What is real is the fact that we are still animals, driven by primal instincts. As a psychiatrist, you must know this to be true.
Carol: To be honest, ambassador, when someone starts talking to me about the truth, what I hear is what they're telling me about themselves more than what they're saying about the world.
#

* The Arrival (1996) | Charlie Sheen in lead role
http://www.imdb.com/title/tt0115571/ [imdb.com]

"Zane, an astronomer discovers intelligent alien life. But the aliens are keeping a deadly secret, and will do anything to stop Zane from learning it."

Zane Ziminski: I come to you with what may be the preeminent discovery of the 20th century, the possibility of extra-solar life, and I get shit-canned for it?

[right before he kills an alien]
Zane Ziminski: Do you want to see the ruins, my friend?
#

* Starman (1984) | Jeff Bridges in lead role
http://www.imdb.com/title/tt0088172/ [imdb.com]

"An alien takes the form of a young widow's husband and asks her to drive him from Wisconsin to Arizona. The government tries to stop them."
#

* The Last Starfighter (1984) | Lance Guest in lead role

http://www.imdb.com/title/tt0087597/ [imdb.com]

A video-gaming boy, seemingly doomed to stay at his trailer park home all his life, finds himself recruited as a gunner for an alien defense force.

#

Starman
and
The Last Starfighter,
when compared together,
is interesting.

In Starman, the "alien takes the form of a young widow's husband"

In The Last Starfighter, the character Alex Rogan goes into space to do battle while a clone,
Beta Alex, is left behind. Notice the lizard reference:

Alex Rogan: Teriffic. I'm about to get killed a million miles from nowhere with a gung-ho iguana who tells me to relax.

(it's all just a clever "mistake"):

Centauri: The amusing thing about this, it's all a big mistake. That particular Starfighter game was supposed to be delivered to Vegas, not some fleaspeck trailer park in the middle of tumbleweeds and tarantulas. So it must be fate, destiny, blind chance, luck even, that brings us together. And as the poet said, the rest is history.

Alex's "twin" or "clone":

Beta: Wait a minute, what are you doing back?
Alex Rogan: Are you kidding? It's war up there!
Beta: Oh, save the whales, but not the universe, huh?

[Beta is about to sacrifice himself]
Beta: [grimly smiling] You owe me one, Alex.

Alex Rogan: Hey, you look like me!
Beta: Of course I do. I'm a beta unit.
Alex Rogan: What the hell is a beta unit?
Beta: A beta unit is a simuloid. An exact duplicate, only not as loud!

Did you read that? "An exact duplicate" - so one tie to the "Starman" movie.

(Ask yourself, have YOU ever had "something", notice I didn't say someone, as to suggest
a human being, ask YOU if you wanted to FIGHT in SPACE? Be honest, now, and you don't have
to tell us, just know inside that that "voice" was of evil) In many "space" themed and
science fiction stories there's often this "split" personality or "other" being involved
somewhere, usually with the leading role.

#

Hebrews 13:2
"Be not forgetful to entertain strangers: for thereby some have entertained angels unawares."

Are they ALL good angels? Are some bad?

Are some people possessed? Do some of these people have their true nature/soul either
extracted from them and the "walk in evil being" is in control or what?

Or are we simply more "self aware" and notice differences in people around us who
are not as self aware? Have we isolated ourselves too much playing games, using computers,
being nerds, etc. and simply notice people aren't as fully animated as television and movie
characters?

I believe there's more to it, and I believe it's spiritual. One crazy commercial had a ton of people riding a train with the "shh!" finger at their lips. I've seen a lot of ads with the "shh!" sign and trains and cars of different colors being used as "spiritual" symbols as vehicles in a spiritual way, colors having their own defining characteristic.

If you watch much television, you've probably noticed the increase in evil themed shows, if people aren't simulated as killing other humans it's zombies, vampires, or showing
vampires and other "evil" creatures as "good", which is a Satanic lie.

#

One thing is for sure, whatever the truth is: I cannot wait for this "ride" to end.

Re:the dark side of the moon IS A TRAP! (1)

rossdee (243626) | more than 2 years ago | (#39656725)

Really? Is that like if you play it backwards you hear the voice of the devil or something
Noom eht yb despilce si nus eht tub enut si nus eht rednu gnihtyreve

it's a FACT. it's on WIKIPEDIA. (1)

Thud457 (234763) | more than 2 years ago | (#39658011)

Don't forget that the movie WALL-E syncs up perfectly with Pink Floyd's "The Wall". A bloody obvious giveaway that you're trapped in The Matrix.

The GRAND Delusion - how to beat it! (-1)

Anonymous Coward | more than 2 years ago | (#39656229)

The Final Battle Is For Your Mind And Soul!

Google: The Mind Has No Firewall, it's written by the military and is a must read!
:
Until they have plugged us all into the internet with our minds and keyboards/mice are tossed behind us, ways to ID us in every aspect of our lives will continue, because the machine of blackops is never satisfied, never full. It won't be until we're all hardwired into the global manufactured, false reality, second life like abomination of Internet 6.0!

Smartphones = lie with a sweet name
patriot act = lies with a sweet name

Just as I'd imagine they'd call some type of legislation against Christianity, the "True Cross act of 2029!" it's all a big game of lies, folks! Lies!

Your soul is what they're after! Rebuke all entities trying to communicate with you in the name of Christ Jesus, Yahweh, Holy Spirit, watch them run, watch them flee! They are scared of the mighty One True God. Do not be fooled by darkness, it has no real power.

But there are those who will accept what these evil entities have to offer, delusion and a false belief they've gained hidden knowledge. Remember, "nothing is new under the sun".

Everything hidden will be exposed when God returns, and the evil creatures fear Him, and rightly so! The humans who have been lulled by these evil entities are afraid, too, they do their best to bash precious Christ, but they will be defeated in the end, unless they choose God. They will be thrown in the same lake the invisible serpents and scorpions will be thrown into.

The "don't tread on me" flag is illuminati garbage, the same snake image is on Metallica's black album cover. The Bible gives Christians the power to TREAD ON SERPENTS AND SCORPIONS and OVER ALL POWER OF THE ENEMY. These are mentions of real, spiritual enemies! They should be tread upon at all times! They are weak but God is strong!

They're running ANCIENT ALIENS on THC and aliens everywhere, occult symbolism in everything you could imagine, popular music, movies, television shows, comics, entertainment magazines, you only need to know what to look for, this whole world is polluted by the occult, they want you to kneel on the commands of evil, do not fall for the trick, do not fall for the false illumination, come to Christ and CLAIM the power over ALL EVIL!

Never forget: The beast system longs to trick and absorb us all, for any true Christian is a threat to the beast system and its lies.

When you gain confidence in your faith, they will send messengers in human likeness or humans taken over to try and pollute your belief, to try and sway you from your faith. If you follow a paganized form of Christianity or give up your belief, the attacks will not be as pronounced, or they may stop altogether, for you will have "fallen away" and aren't a spiritual threat.

WE are ETERNAL beings, the powers of darkness despise this and want to rob us of our heavenly place in our heavenly home.

Avoid ghost-hunter shows, anyone searching for ET or other such garbage, they are all manifestations of the same evil. Trust God and His Word. People posting against this truth are likely a part of the delusion.

The cover of The Dark Side of The Moon album is illuminati proof, summed up in one photo, of a (spiritual) transformation which is a lie. Don't be fooled by creatures appearing as light or bathed in light or blinding you in light. Reject them all through Christ and they will flee like the cowardly vermin they are.

Re:The GRAND Delusion - how to beat it! (1)

Confusedent (1913038) | more than 2 years ago | (#39656881)

It's all so obvious now.

Re:The GRAND Delusion - how to beat it! (1)

doston (2372830) | more than 2 years ago | (#39657719)

You should teach this in Tennessee!!

Truecrypt Tor RAM and TALK 2 THE HAND! (-1)

Anonymous Coward | more than 2 years ago | (#39656285)

Theres a lot to be said about running The Tor Browser Bundle in an encrypted container (TrueCrypt) on a LiveCD, with the hard drive UNPLUGGED and UNUSED!

(just take the hard drives out and never use them again, USB thumb drives are cheap and can be encrypted with TrueCrypt, too, as an encrypted containter, partition, or the whole drive itself, just never use a proprietary OS like Windows or Mac OS X)

As a primer, read:

#Tor OPSEC Operational Security
Great Resource of Information!

cryptome.org/0005/tor-opsec.htm

And:

#Lest We Remember: Cold Boot Attacks on Encryption Keys

citp.princeton.edu/research/memory

If the keys (TC passwords) are in my head, complex enough, and never written down.

With the amount of RAM present in new computers, I see no logical reason to use a hard drive again when Linux LiveCDs, encryption, and thumb drives are on the cheap or free.

No unsafe hardware sex, either, this means no plugging your Tor/Truecrypt thumb drive into another system, any system, except for your Tor/Truecrypt system.

Run audits on your system, verify LiveCDs, make sure your router isnt backdoored like many or maybe all of the Cisco routers. Keep up to date if you use open source firmware for your routers. Consider replacing proprietary routers with an older PC as a router with an open source OS like OpenBSD or a prerolled firewall distro.

Test your connection with remote nmap, dabble with Snort, Tripwire and other monitoring tools.

Dont use external hard drives.

RAM is your friend, always.

Re:Truecrypt Tor RAM and TALK 2 THE HAND! (0)

JustOK (667959) | more than 2 years ago | (#39656365)

ur never safe until you start making your own processors.

Tasty aliens... (3)

mevets (322601) | more than 2 years ago | (#39656343)

If we share common ancestry, that means we might find alien life tasty and nutritious. ... to seek out new life and new civilizations, to eat.

Re:Tasty aliens... (2)

ZeroSumHappiness (1710320) | more than 2 years ago | (#39656591)

To Serve Man, anyone?

Re:Tasty aliens... (1)

FoolishOwl (1698506) | more than 2 years ago | (#39657107)

Panspermia seems like it would make for a good handwave in science fiction why humans could find edible food on an alien planet, or have to worry about alien diseases. I have a hard time believing life could actually spread from planet to planet this way. But I'm not a physicist or biologist.

Really? (1)

srees (1290588) | more than 2 years ago | (#39656601)

I had no idea the theory of an asteroid impact had been proven as fact. Glad I read slashdot so I can stay educated.

Re:Really? (1)

geekoid (135745) | more than 2 years ago | (#39658019)

yeah, it's a fact. Giant craters, layer of material around the globe. etc...

Fermi's Paradox solved. (1)

tekrat (242117) | more than 2 years ago | (#39656655)

So, without realizing it, we're ALREADY colonizing our galaxy. Life bearing rocks from earth hit other planets, those planets also experience trauma sooner or later, ejecting their rocks into space millions of years later, after life had caught on, and so on and so on.

Therefore, Earth may be a colony of some other civilization from billions of years ago, or, we're creating colonies as we speak.

How did life survive the heat of the impact (1)

rossdee (243626) | more than 2 years ago | (#39656763)

I could believe that some simple life form could suvive on a rock travelling through space for millions of years, but I don't see how it would have survived the heat of the impact event that blasted it beyond escape velocity in the first place

(at least life as we know it, Jim)

Re:How did life survive the heat of the impact (0)

Anonymous Coward | more than 2 years ago | (#39657567)

What if it's in the rock?

Re:How did life survive the heat of the impact (1)

ceoyoyo (59147) | more than 2 years ago | (#39658085)

Most non-dinosaur killing meteorites land cold.

Aliens not so alien? (1)

Anonymous Coward | more than 2 years ago | (#39656773)

So the implication is that if this is true then if life is one day to be discovered within the subsurface oceans of either Europa or Enceladus then it's possible that such life originated from Earth, and therefore from the same root single celled organism (the Eve cell) from which all terrestrial life came from. If so a mitochondrial DNA check would verify this.

Re:Aliens not so alien? (0)

Anonymous Coward | more than 2 years ago | (#39657907)

Confirmation of why all the aliens on network sci-fi were humanoid! And why the aliens on Aliens found us so tasty!

ummm...? (1)

um... Lucas (13147) | more than 2 years ago | (#39656809)

How can we study the trajectory when we don't know:

When the asteroid hit?

The earth's position relative to the sun, the other planet, and the rest of the stars in the galaxy at the time of impact.

The direction from which the asteroid hit us.

The size of the asteroid.

For starters....

An OK theory for other planets, but not ours? (1)

jmulvey (233344) | more than 2 years ago | (#39656897)

Panspermia is a very interesting/compelling theory. But I'd avoid telling anyone in academia that you're interested in an Earth genesis hypothesis other than evolution.
You may just as well have told them that you're a pro-lifer, who voted for Bush, are home schooling your kids, believe in a balanced budget, and are a racist all in one sentence.

Re:An OK theory for other planets, but not ours? (2)

blueg3 (192743) | more than 2 years ago | (#39657537)

Evolution isn't an origin-of-life theory. You're thinking of abiogenesis.

Re:An OK theory for other planets, but not ours? (1)

Hatta (162192) | more than 2 years ago | (#39657747)

I'd avoid telling anyone in academia that you think evolution is an "Earth genesis hypothesis".

Re:An OK theory for other planets, but not ours? (1)

ColdWetDog (752185) | more than 2 years ago | (#39658073)

Oh bullshit. Panspermia has been around for decades and lots of mainline scientists (including Francis Crick, one it's earliest proponents) have thought it interesting.

But it is more entertainment than anything else - until we get off planet enough to test it. A dozen probes to Mars and a Europa would be good start, but as always - if you've got the money, I've got the time....

Wait (0)

Anonymous Coward | more than 2 years ago | (#39657081)

All this talk about ejaculates and sperm theory, and NOBODY's made a joke about it yet?

simple math, brought to you by Google Calculator (3, Interesting)

Lluc (703772) | more than 2 years ago | (#39657429)

Assume we're just dealing with Carbon (molecular weight 12) here, and "well over 1 trillion tonnes" is actually 2 trillion tonnes:

number of molecules per gram = (Avogadro's Number) / 12 grams = 5.02E25 molecules/kg
2 trillion tonnes = 2E15 kg
(5.02E25 molecules / kg * 2E15 kg) = 1.004E41 molecules

Surface area of sphere with radius of 20 light years = 4.499E35 meters^2

1.004E41 molecules / 4.499 meters^2 = 223,091 molecules / meter^2 == 4.44 attograms of carbon per square meter.
This is a pretty thin layer of material to survive reentry on some 20 light year distant planet.

--------
Alternatively, from google: ((Avogadro's number / (12 grams)) * (2 trillion tonnes)) / (4 * pi * ((20 lightyears)^2)) = 0.223099739 kilometers per liter = 0.5 miles/US gallon, which means we totally need to collect some gas guzzler tax on this material

Krrryptonite! (0)

Anonymous Coward | more than 2 years ago | (#39658101)

Somewhere on Gliese 581's "Earth" is a Lex Luthor dinosauroid plotting the demise of Supersaur using radioactive fragments from his home world.

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