Earth-Generated Panspermia

Jupiter's Moon Europa A new simulation found that high-velocity particles ejected from Earth could make their way to the Jupiter system, where they could conceivably land on a moon like Ganymede or Europa, shown here. Europa is thought to harbor a massive ocean.

Proponents of panspermia theory say life on Earth came from elsewhere, hitching a ride on rocks sheared from other worlds or from migratory asteroids. But what if life did originate here and then it left, hitching a ride on Earth-departed rocks? Earth could seed other worlds, instead of the other way around. A new analysis says the rocks could conceivably make it as far as Jupiter.

 

Scientists have found several meteorites that originated on Mars or the moon, after being ejected in asteroid collisions, forcefully thrown into space and finally arriving on Earth. It makes sense that the opposite could be true, and that after mega-collisions, some pieces of Earth could be thrown toward Mars or Venus.

But most simulations suggest very few Earth pieces would reach the fourth planet, because they would have a hard time overcoming the gravitational pull of both Earth and the sun. Lots of the ejected particles would actually wind up back on Earth, according to previous studies. Some scientists have even suggested these refugee particles would “re-seed” their home planet.

Now researchers in Mexico have a new simulation, and they say plenty of Earth bits would indeed make it to Mars — and beyond, all the way to the Jovian system. Mauricio Reyes-Ruiz and colleagues at the Universidad Nacional Autonoma de Mexico ran computer simulations of 10,242 test particles, following their predicted paths for 30,000 years. That’s about as long as scientists think life could survive in space, the authors note.

They ran simulations at five different ejection velocities, from 6.97 miles per second to 10.2 miles per second. They found that at faster velocities, particles are more likely to reach Jupiter than Mars, because of their great speed relative to Mars’ low gravitational pull. The particles also reach Jupiter more quickly, with half making the trip in 10,000 years, the authors write. In one simulation, just one particle reaches Mars, and it takes between 25,000 and 30,000 years to get there.

Even more bizarre, many particles end up traveling past 40 AU, which the authors describe as leaving the solar system. 

This is all theoretical, of course — the ejection velocity and the particles’ trajectory would be determined by variables like the size and velocity of the incoming object, not to mention the collision location relative to the spin of the Earth. But it’s an interesting concept — as KFC points out over at Technology Review, if life persists in space longer than astrobiologists think, life from Earth could still be speeding toward distant worlds.

 by "environment clean generations"

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Posted in: earth,ejection,europa,panspermia,particles,scientists,velocity

Panspermia-Moral Obligation or BioPollution

The speculative mechanism of panspermia could explain how life formed on Earth and how it might exist elsewhere in our solar system and beyond. Hitching rides on chunks of rock blasted into space by meteorite impacts or gliding through space on a comet, it turns out that "life as we know it" has an astonishing knack of surviving in the most extreme environments.

            But what if mankind could purposefully launch space probes packed with little biological "starter kits" toward star systems that appear to have the potential to nurture life? We have lots of life down here, isn't it our duty to spread our seed amongst the stars?

  

           Yes, says Michael Mautner, Research Professor of Chemistry at Virginia Commonwealth University, in a paper submitted to an upcoming issue of the Journal of Cosmology. Before the rich biosphere of Earth is dead, Mautner believes that we need to ship Earth Brand™ biology to suitable adopted homes so our evolutionary line has a chance to gain a foothold elsewhere in the universe.

           "We have a moral obligation to plan for the propagation of life, and even the transfer of human life to other solar systems which can be transformed via microbial activity, thereby preparing these worlds to develop and sustain complex life," Mautner said. "Securing that future for life can give our human existence a cosmic purpose."

           

            These are certainly lofty plans, but he proposes that we send a variety of basic organisms to "potentially fertile" worlds throughout the universe (to worlds from a few to over 500 light years away). Using early-Earth as an example, organisms like cyanobacteria could be sent to alien worlds to go into reproductive overdrive, feasting on toxic gases and releasing byproducts such as oxygen. 

            These little biological starter kits would support a brand new biosphere, helping more complex life forms to develop and evolve.

(Is anyone else thinking this was borrowed from the plot of Star Trek III: The Search for Spock?)

             In his paper, Mautner goes into some detail about what this galactic seeding mission would look like. As current launch costs are astonishingly high (using current technology, it costs $10,000 to get a one kilogram payload off the Earth's surface and into space), the space seeding pods would need to be small. But using tiny "pods" weighing only 0.1 grams, as many as 100,000 microorganisms could be accommodated to give a reasonable chance of success.

            Perhaps surprisingly, he indicates that we'd need "hundreds of tons" of biological material. But in this case, the launch costs would be a modest $1 billion; a bargain considering we'd be ensuring the continuation of Earth Brand™ life on various new worlds.

           All these plans are completely speculative however, and to put a cost on such a mission is fanciful at best. Although Prof. Mautner does a great job of identifying how we could go about flinging our seed to the furthermost reaches of the galaxy, I'd question the fundamental point of "directed panspermia" at all. Is it really our "moral responsibility"?

           I understand that we -- as life forms -- see the whole life thing as sacred, but what if one of these biological pods fertilizes a world where another life form is struggling to survive? Who are we to say that our Earth Brand™ life is superior to another brand of alien microbe? 

           If our life takes hold of a planet where another life had the opportunity to evolve into an interstellar civilization in a couple of billions of years time, wouldn't we be in violation of some kind of cosmic anti-monopoly regulation (or at least in violation of the Prime DIrective)?

       

           And there's another thing to ponder: What if "life" is the universal equivalent of some kind of infection. Is life rare because the universe has a very strong immune system? Firing our genetic code far and wide could be considered to be biological pollution. 

           I'm all for spreading the human influence around the galaxy, but I think this can only be considered if we physically go to these alien worlds, to evaluate these places in person before we start setting up home. Blindly sending life from Earth to habitable worlds and planet-forming accretion disks seems a little reckless, especially as we have no clue about the consequences if we started impregnating unsuspecting planets.

          I know these points are just as speculative as Mautner's paper, but it does make you wonder whether sending it into space is really a "moral responsibility" when we have little clue about who or what we are in the grand (cosmic) scale of things.

          Just because we've got it doesn't mean the rest of the universe wants it.

 by "environment clean generations"

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Posted in: earth,microbes,panspermia