From: utzoo!decvax!cca!REM@MIT-MC@sri-unix Newsgroups: net.space Title: closed ecosystems Article-I.D.: sri-unix.1621 Posted: Thu Jun 3 08:04:43 1982 Received: Fri Jun 4 05:03:31 1982 From: Robert Elton MaasAfter the reported round-1 closed-ecosystem experiment, I suggest the following plan: Divide each of the round-1 successful systems in half, resealing one and conducting a detailed analysis on the other. The main thing to find out is whether any materials toxic to human life are abundant in the successful closed ecosystems. Throw out those which are toxic. For round-2, attempt to construct a large ecosystem containing exactly what was determined to be in each of the non-toxic successful ecosystems. Of course some tiny but necessary lifeform will be omitted, but if the first round-2 experiment with pure materials fails we can try again with a small amount of natural crud thrown in (i.e. throw in a small amount of what started the original experiment). With the system dominated by the analyzed result of the round-1 experment, but with crud thrown in to supply a seed crop of anything else needed, I expect each round-2 experiment will stabilize to exactly what the corresponding round-1 experiment did, rather than jumping to some other stable mix. This should be verifiable by comparing analysis of the round-2 results with the correspond round-1 analyses. Next, I guess we need to perform perturbation tests on the successful round-2 mixtures. See if we can add a foreign substance and have the mixture return to its original state after a while. We may find there are a finite number of stable mixtures, that adding foreign substances either returns to the same mixture or jumps to another, and we may find a recipe for jumping a mixture from any existing state to any desired state. Hopefully there's at least one stable mixture that has a high ambient level of oxygen (sufficient for human breathing) and is stable against moderate amounts of oxygen-removal algae-removal and human-waste-return. If so, we've solved the space-station problem. I hope they have funding for additional research!