Interstellar Prescreening, brought to you by Lockheed Martin and the Sentinel Mission

One response to “Interstellar Prescreening, brought to you by Lockheed Martin and the Sentinel Mission”

1. 

   jurvetson

   Nov 6, 2014 at 11:50 pm

   Searching my laptop for Interstellar panspermia, I found something I wrote a while ago, and it starts with a quote from Sir
   Arthur C. Clarke no less: “The stars are not for man, that is, not for biological humans 1.0”

   Certainly for interstellar travel, we would send the data, not the DNA. The timeframes and radiation exposure make the transmission of tissue a pointless paper exercise. This is unfortunate, of course, to all of our dreams of exploration, using the bodies we are so accustomed to today. But, technology will advance. Today, we could already “send the data not the DNA” for microbial life transmission, purposeful panspermia if you will. (And perhaps that’s what seeded our oceans on Earth).

   We would send robotic probes to the distant stars, with the precursor chemicals for a synthetic biology rig to assemble the DNA locally, ideally incorporating feedback about the local environment (food, shelter, clothing for the microbes if you will, given what kind of world we have found with a planet/moon-picking optimizer using remote sensing before landing). The biological matter compiler, would insert the DNA into zombie cells (lacking any DNA, and relatively immune to soft errors from prolonged radiation exposure during the trip) and off they go. So the long trip to the distant system would contain inert chemicals and no physical DNA that needs protection, and no biological life needing food and breeding over the eons. We can protect the data more easily than the biology.

   I have been meaning to share the story of a conversation I set up between Craig Venter and Scott Hubbard (who led NASA’s Mars program, and before that, NASA’s astrobiology program). It was fascinating. The Mars program has been focused on a long series of steps to prepare for a “sample return” from Mars, to bring back putative signs of life for analysis here on Earth. This material return is quite expensive (just like the moon missions, sending a probe to the moon is a fraction of the complexity and cost of bringing a spacecraft back).

   So Craig’s idea is to do a sample return without the complexity of a return flight and the cost of escaping the Martian gravity well.

   We would send a gene sequencer to Mars, modified perhaps for a wider range of nucleic acids (but some argue that the RNA and DNA set may likely be conserved across the solar system based on theories of the timing and continuity of panspermia, with a ton of material still transferring naturally between Earth and Mars every year).

   So the sequencer would be on a robotic rover (which may be a cave diver or drill probe to get to the likely zone of life. Like Earth, most of the living biomass would be a fair bit underground).

   And, for those who worry that we might discover a castaway microbe from Earth, the answer is fairly simple, if it’s indigenous to Mars, it will live in a colony, and there will be many of them. If it came from Earth, it is very unlikely to propagate into a colony in the local environment (and if it did, that would be a fascinating discovery in its own right, offering a harness for biological terraforming of the abundant CO2 to oxygen).

   With the discovery of microbes (living or potentially even deceased), we would sequence locally, and beam the data back to Earth.

   On Earth, we could study the data, which would be fascinating in its own right. But Venter would take it a step further and boot up a living cell with the Martian DNA here on Earth. We can easily synthesize the physical DNA with just the data. Venter has already demonstrated that this “genetic alchemy” is possible, by removing 100% of the DNA from a microbe, replacing it with a foreign bolus, and converting the cell into the foreign species — a free-living organism that created a trillion offspring. He can print to life, and the software creates its own hardware. So this would be a living sample return. We could call it the Andromeda Strain.

   While this may be a great way to explore our solar system and local environment, the speed of light makes the exploration and colonization of any other solar system a frustrating exercise. We have to wait for eons to find out how it went for the distant probes.

   Some hypothesize that the inaccessibility of most of the universe is a sign that we live in a simulation, where the distant celestial bodies can be rendered with simple algorithms, much like immersive worlds in the games we play today. It all results from the peculiar and apparently arbitrary limit of the speed of light. As we look farther out, the view becomes degraded and eventually collapses to a singular event as we look back in time. And we can’t go there. It’s beyond reach, and that seems just so convenient. Much like the Planck length limit to the voxels of our world — the Minecraft cubes of inner space.

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