04:36 pm
December 3, 2010
Ok, now we have arsenic life. But here's a much wilder thought: How about living clouds?
Sean Heavey/The 2010 National Geographic Photography ContestA supercell thunderstorm rolls across the Montana prairie at sunset.
I assume you've read the news. To life as we know it, with carbon, oxygen, nitrogen, hydrogen, sulfur and phosphorous, we can now add life with arsenic. Dr. Felisa Wolfe-Simon fed a little bacterium daily doses of the dread element, and the little guy slurped it up, chucked most of its phosphorous, and became an arsenic-creature. "It's a really nice story about adaptability of our life form," chemist Gerald Joyce told the New York Times, "It gives food for thought about what might be possible in another world."
Well, here's one possibility. The otherwise sane and respected astrobiologist David Grinspoon has been considering that under the right circumstances, clouds could become living things. With intelligence, even. Carl Sagan thought so, too.
NASA/ESA/JPL/Arizona State Univ.We think the Crab Nebula looks super intelligent.
A living thing, it is thought, needs to feed, grow, copy and evolve and persist. It needs some kind of shape. Clouds can do all that, says David Grinspoon. Though they look hazy and random here on Earth, they contain levels of order, they hold themselves together, they move around, they have routines. They can, in theory, produce increasingly complex forms of themselves.
Says Grinspoon:
Stuart Kauffman talks about life in an abstract sense as a system that uses energy and builds complexity out of flows and gradients of energy and matter resulting in something that self replicates, so Darwinian evolution can take over.
If you look at that as an abstract idea of what you need – constant flows of energy and nutrients to provide templating building blocks — then you ask, "What kind of environment provides those sources of energy that facilitate complexity?"
Imagine a cloud of stellar dust several light years across quietly drifting through space. Powered by its own bursting stars feeding it oxygen, carbon, life-giving chemistries, could it not become a slightly lonely but vastly oversized life form? An enormous space traveler?
NASAGalactic Drifter: a star-forming region in the Carina Nebula.
About 50 years ago, the astronomer Fred Hoyle wrote a science fiction book called The Black Cloud, in which a huge interstellar cloud becomes a thinking being. It uses gravity as its container.
Astronomer Chris Impey says that little kids who read Hoyle's book – and lots of them did — are now grownups. They have put his fanciful notions into equations and, alas, the idea doesn't quite work:
Unfortunately, in real life the density of interstellar gas is so low that interactions would take place hundreds or thousand of times slower than that in a liquid medium on Earth. Hoyle's idea is implausible, but it's hard to rule out.
But what about a local cloud? One, say, on Jupiter or Venus?
Grinspoon says when our probe landed on Venus, the place looked dead. We saw no signs of life.
But we overreacted. There can't be life as we know it on the surface of Venus, but there is the possibility of life in the clouds of Venus — they're within the right temperature range for life as we know it, and they are in a continuous, dynamic environment, one with a lot of interesting energy sources and a certain amount of chemical equilibrium in the atmosphere that has not yet been well explained.
Maybe Jupiter?
Grinspoon's mentor and friend Carl Sagan thought that Jupiter could have buoyant creatures floating in its clouds. He called them "floaters" and "sinkers," and he and another scientist made up an imaginary world of Jovian clouds hanging out together. So far, no one has detected clouds on Jupiter humming to each other, but cloud life isn't the only idea being explored. Astrobiologists are thinking about self-organizing electric fields and magnetic fields (whatever they are). But far from the lab I bumped into a group of weavers who've been knitting neurons in wool…
Gabrielle TheriaultA hand-knit neuron, the perfect gift for your favorite neuroscientist.
I don't think these "brain cells" are even remotely alive – though they are gorgeous — but as Chris Impey says: "The possibilities may simply be limited by our imaginations."
David Grinspoon is Curator of Astrobiology at the Denver Museum of Nature and Science and an Adjunct Professor of Astrophysical and Planetary Science at the University of Colorado. He was interviewed by astronomer Chris Impey. The interview appears in Impey's new book "Talking About Life, Conversations on Astrobiology"(Cambridge University Press, 2010). Living Clouds are also discussed in Impey's book "The Living Cosmos" (Random House, 2007), and while I am blushing as I say this, Radiolab was thinking about arsenic and life a year ago. The first cloud photo is a submission from National Geographic's 2010 photo contest. Check out their Web site to see other 2010 submissions, vote on your favorites and see past winners.
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yuan sun (ysun) wrote:
on the fifteenth of june, in the garden of nigel
in the light of the moon, in the shadow of rigel
he was melting stones... enjoying earth's bones
when horton the horta was shot by a phasorso horton cried in pain. tried to run from kirk in vain.
till spock did a meld and bones healed with his powers he held.
then horton found the miners new veinsFri Dec 03 2010 18:16:07 GMT+0000 (GMT Standard Time)
Nigel Tufnel (fishnut) wrote:
I found a Horta in my garden this summer. I call him "Horton".
Fri Dec 03 2010 18:00:24 GMT+0000 (GMT Standard Time)
yuan sun (ysun) wrote:
"We like to think of ART as alive. In reality it's just a BAG OF CELLS in dynamic processes. It provides a home for GLOWING SOUL but a CELL, itself, is not a living organism."
Fri Dec 03 2010 18:00:01 GMT+0000 (GMT Standard Time)
Art Aficionado (Art_Aficionado) wrote:
We like to think of the Earth as alive. In reality it's just a rock with dynamic atmospheric and geologic processes. It provides a home for living organisms but a rock, itself, is not a living organism.
Fri Dec 03 2010 17:38:55 GMT+0000 (GMT Standard Time)
Johnathan Wilbanks (JMWilbanks) wrote:
The more we learn about the universe the fewer differences we find between inorganic matter and what we consider to be life. Life is, in essence, a rather complex and continuous series of chemical and electrical reactions. Expanding the definition to include gravitational interactions and such really isn't meaningful because there is no defining line between what is life and what isn't. Rather than suggesting that everything in the universe is alive, I suggest that it's all dead. Our perception is valuable only to us - let's expand the scope of the Copernican Principle again!
Fri Dec 03 2010 17:20:43 GMT+0000 (GMT Standard Time)
Paul D (pixelD) wrote:
That picture of the cloud is very scary.. Glad we don't get those in these parts.
Fri Dec 03 2010 17:16:10 GMT+0000 (GMT Standard Time)
James Harvey (J01) wrote:
Funny how what we concieve as possible is so thoroughly constrained by what we know:
"Unfortunately, in real life the density of interstellar gas is so low that interactions would take place hundreds or thousand of times slower"
- does life have to proceed on the same time scale elsewhere as it does on Earth? Is it possible that there is life that has such a slow metabolism that we cannot detect it in a human lifetime? Any fundamental reasons why/why not?
"There can't be life as we know it on the surface of Venus, but there is the possibility of life in the clouds of Venus — they're within the right temperature range for life as we know it"
Life as we don't know it seems just as likely, if not more likely, to exist. Why not silicate life forms at 1200°C?
Fri Dec 03 2010 17:02:19 GMT+0000 (GMT Standard Time)
Friday 3 December 2010
Arsenic Life Is Nice; Living Clouds Are Nicer : Krulwich Wonders… : NPR
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