supply of breathing gas, and the control station monitors the deployment and communications with the divers. Primary gas supply, power and communications to the bell are through a bell umbilical, made up from a number of hoses and electrical cables twisted together and deployed as a unit. This is extended to the divers through the diver umbilicals. The accommodation life support system maintains the chamber environment within the acceptable range for health and comfort of the occupants. Temperature, humidity, breathing gas quality sanitation systems and equipment function are monitored and controlled. Experimental life-support systems MELiSSA Micro-Ecological Life Support System Alternative (MELiSSA) is a European Space Agency led initiative, conceived as a micro-organisms and higher plants based ecosystem intended as a tool to gain understanding of the behaviour of artificial ecosystems, and for the development of the technology for a future regenerative life-support system for long term crewed space missions. CyBLiSS CyBLiSS ("Cyanobacterium-Based Life Support Systems") is a concept developed by researchers from several space agencies (NASA, the German Aerospace Center and the Italian Space Agency) which would use cyanobacteria to process resources available on Mars directly into useful products, and into substrates for other key organisms of Bioregenerative life support system (BLSS). The goal is to make future human-occupied outposts on Mars as independent of Earth as possible (explorers living "off the land"), to reduce mission costs and increase safety. Even though developed independently, CyBLiSS would be complementary to other BLSS projects (such as MELiSSA) as it can connect them to materials found on Mars, thereby making them sustainable and expandable there. Instead of relying on a closed loop, new elements found on site can be brought into the system. See also Footnotes References Further reading Eckart, Peter. Spaceflight Life Support and Biospherics. Torrance, CA: Microcosm Press; 1996. . Larson, Wiley J. and Pranke, Linda K., eds. Human Spaceflight: Mission Analysis and Design. New York: McGraw Hill; 1999. . Reed, Ronald D. and Coulter, Gary R. Physiology of Spaceflight – Chapter 5: 103–132. Eckart, Peter and Doll, Susan. Environmental Control and Life Support System (ECLSS) – Chapter 17: 539–572. Griffin, Brand N., Spampinato, Phil, and Wilde, Richard C. Extravehicular Activity Systems – Chapter 22: 707–738. Wieland, Paul O., Designing for Human Presence in Space: An Introduction to Environmental Control and Life Support Systems. National Aeronautics and Space Administration, NASA Reference Publication RP-1324, 1994 External links Environmental Control and Life Support