Ell Donsaii 13: DNA by Laurence Dahners Read Free Book Online Page A

enormous dome shaped balloon with graphene walls. As you know, graphene is astonishingly strong and so the material of our dome can be very thin leading to its translucent appearance. The dome’s about a kilometer in diameter and a couple hundred meters high.”
    “And what’s its purpose?” Alton asked. “I see what looks like an airlock there on the side facing us. Are you Martians planning to move out of your tunnels and into the dome?”
    “Oh, no! We’re living in the tunnels because there’s so much radiation here on Mars. We still need to live underground most of the time or we’d quickly accumulate an overdose in this environment. In the dome the radiation level would still be high so it’d be just as unsafe to live in it as it is on the surface. No, this is an experiment aimed towards determining whether it might be possible to terraform Mars someday.”
    “By ‘terraform’ I understand you mean endeavoring to make Mars more like Earth so that people could possibly live there?”
    “Yes Sir,” Lindy said, reverting to her military speech patterns. “What we’ve been doing so far is using ports donated by Portal Technology to bring carbon dioxide into the dome from balloons floating in the atmosphere of Venus and nitrogen from the atmosphere of Titan. We also have ports bringing in water from the ocean underneath the icy surface of Europa, the sixth moon of Jupiter.”
    Rupert said, “I can understand why you might want to bring water to Mars, but why would you be bringing carbon dioxide?”
    “Well,” Lindy said, “the only place in the solar system that has a lot of free oxygen is earth. We don’t want to steal Earth’s atmosphere to create an atmosphere here, so what we need is something we can convert into an atmosphere using photosynthesis. For that, we need four things—light, photosynthetic organisms, carbon dioxide and water. Back home on earth, the oxygen we breathe is created by plants that use sunlight to make carbohydrates and oxygen out of carbon dioxide and water. If we can get photosynthesis going here on Mars, conceivably we can use CO 2 from Venus and water from Europa to make both food, i.e. carbohydrates, and oxygen for our colonists.”
    “That sounds like a great way to do it. What kind of plants are you going to start growing? Potatoes?”
    “Well, as you know, we’re already growing potatoes in underground tunnels here on Mars. But, what we’re expecting to use to create atmosphere will be cyanobacteria, which are often called blue-green algae. It’s thought that cyanobacteria may be what originally converted Earth’s atmosphere from carbon dioxide to oxygen about six hundred million years ago. Potatoes and other plants that are more familiar to us need oxygen themselves, so they won’t do well in an atmosphere that has high concentrations of carbon dioxide and virtually no oxygen. We won’t be able to grow those kinds of plants until the cyanobacteria have done their job. Also, remember we’re doing this on the surface of Mars where there’s a lot of radiation. Bacteria tolerate radiation a lot better than multicellular plants.”
    “Is there enough light here on Mars? I would think there’d be less than there is on earth, and even though the graphene dome is fairly translucent, it must block some light.”
    “You’re right,” Carol said, “but fortunately we can use parabolic mirrors in near solar orbit to send large quantities of sunlight through small ports suspended at the top of the dome.”
    “That sounds problematic in its own right,” Rupert said. “Since radiation is a major problem here on Mars, won’t those ports be bringing in even more high energy solar particles?”
    “Oh, no. It’s hard to reflect high-energy particles and the parabolic mirrors don’t reflect it at all, so the ports really don’t get any dangerous radiation to transmit, only light.”
    “It sounds like you’ve got a pretty foolproof plan. Do you anticipate any