Allotropes (an Ell Donsaii story #8) Read Online Free Page B

rockets as viewing platforms to astronomers who might want to simply observe those systems optically.”
    Shan narrowed his eyes, “But it sounds like Sigma Draconis has more advanced life. Is it intelligent?”
    “Shan, they’ve built a ringworld.”
    “My God! All the way around the sun, like in Niven’s book?”
    “Oh, no! Niven’s ringworld wouldn’t have maintained a stable orbit and it would have to have been built out of material with absolutely impossible tensile strength. There are countless things on Niven’s ringworld that are not only impossible with current tech but will probably never be possible. No, the Sigma Draconis ring is only 20,000 kilometers in diameter. It’s turning eight revolutions per day. It could be constructed with carbon nanotubes or graphene, if you could make enough of those carbon allotropes.”
    “Holy crap Raquel! That’s still freaking enormous! A circumference of 63,000 kilometers! How wide is it?”
    “About 5,000 kilometers.”
    “So that’s what… 315 million square kilometers of surface!?”
    Ell nodded. “About 60% the surface area of the earth. A lot bigger than their homeworld.”
    “How thick is it?”
    “Can’t tell, but even if it were only five meters thick, that would still require 1.6 million cubic kilometers of carbon assuming they built it out of graphene.”
    Shan closed his eyes, “That kind of engineering… that’s just plain scary,” he whispered.
    Ell raised an eyebrow, “You’re telling me.”
    “So, is the life there DNA based?”
    “The first specimen, a plant, was.” Ell glanced up at her HUD. “Oh, and the second plant was DNA based too. Seems like the DNA molecule is pretty ubiquitous.”
    “What are the intelligent beings like?”
    “Haven’t seen one yet.”
    “Really? They built a ringworld but aren’t living there?”
    Ell shrugged, “I don’t know. So far all Sigwald has encountered are fields of what appear to be crops. At first they seemed to only be one type, but he’s just encountered a second kind of plant.”
    “Sigwald?”
    “My name for the waldo that’s actually on the ringworld.”
    He got a distant look, “Maybe the plants are intelligent?”
    Ell shrugged, “Can’ t rule that out, but the plants we’ve seen don’t have hands. How would they build a ringworld?”
    “Can I see?”
    Ell ported the video from Sigwald to Shan’s HUD and he leaned back, flabbergasted as the view from Sigwald raced along the road between the fields. A road that shot arrow straight into the distance until even the transparent atmosphere had deflected enough light that nothing could be seen but a bluish haze. High in the far distance he thought perhaps he could see a wall rising up above the haze. “Is the bottom of the ring flat from side to side?”
    “No, it’s dished some toward the middle. In just a few minutes the sun will go down and you’ll be able to see the other side of the ring because that side’ll be the one lit by the sun. You’ll be able to see that there appears to be a blue circle sea running along the middle of the ring. That would fit with the middle being the deepest part of the ring. Water would run from the rims down to the central circle sea. A typical weather cycle could then evaporate water out of the sea. The water vapor would rise and move to the higher edges of the ring. When the air got to the higher altitudes near the rimwalls it would precipitate out as rain and start running back downhill across the fields again.”
    Shan glanced around the edges of the field of view in Sigwald’s camera, seeing some clouds he hadn’t paid attention to before. “Wouldn’t rain wash all the soil down to the sea without tectonics to raise some land again?”
    Quietly Ell said, “I think the ring’s like a huge hydroponic system. No real soil, other than the composting of previous crops to release soluble nutrients. They must have some way to pump nutrient elements back out to the edge of the ring