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Elaine Walker's Personal Journal - HMP 2004 Education and Public Outreach July 30, 2004 After breakfast, Alain Berinstain (Canadian Space Agency/University of Guelph), current Principal Investigator of the HMP's Arthur Clarke Mars Greenhouse, gave a tour of the greenhouse after breakfast. When most people walk into the greenhouse for the first time, they are in awe of the level of technology in place. There are computers, control boxes, and various types of sensors mounted on the walls and ceiling. There are heaters and batteries on the floor, and racks of white containers - half containing small sprouts of lettuce, and the other half planted with seedlings ready to grow once commands are given from back on "Earth". All of the individual containers are fitted with moisture level sensors. Light sensors are mounted nearby, and temperature sensors hang from the ceiling in various places. There are intake vents and exhaust fans for cooling (they let out the warm air). It is interesting to note that even in the High Arctic, it is necessary to both heat and cool the greenhouse. Just before I arrived on Devon Island, the team had worked very hard in difficult weather conditions to erect two windmill structures to provide power to the greenhouse. Two solar panels also provide power. The wind and solar power are combined and serve a basic function to charge a set of batteries. The batteries generate the 24V DC line that powers the main computer for data acquisition and control (nicknamed "Rama") and the exhaust fans. This 24V power is then stepped down to 12V and 5V, to power circulation fans, pumps, the packet terminal for satellite communications, as well as the small computer that controls communications and acts as a time server (nicknamed "Arthur"). If the batteries are fully charged, and the power generation system is generating excess power, a load diverter will send current to a heating coil in the heat recovery system, that will in turn heat a large mass of water, thereby storing all extra energy. This warm water is used to augment the propane heating system in the greenhouse. With all of this in place, they are able to have completely independent power and not have to rely on the NASA HMP base camp generators. With all of the greenhouse subsystems operational (heating, cooling, plant growth, heat recovery system and satellite communications), the team conducted a series of tests and debugging, culminating in full autonomous operation. At this point, all primary and secondary objectives have been met and the team is wrapping things up. Departing on today's twin otter flight are Tom Graham (University of Guelph), Sathya Hanagud and Massimo Ruzzene (both of Georgia Institute of Technology), Tom Kennedy and Eric Mumm, (both of Honeybee Robotics), Howard Cannon (NASA Ames), JD Polk, MD (NASA JSC), Mark Stevenson (CNN) and Katia Clarens (Le Figaro Magazine). Arriving today were Rick McCluskey, MD, (NASA JSC), Paula Lindgren (University of Aberdeen, graduate student, research assistant to Dr. John Parnell), Kyoichi Sasazawa (Japan Daily), and Rhoda Akeeagok (High School student, Grise Fiord). Once again, John Parnell (University of Aberdeen, geologist and geochemist) was fitted into the Hamilton Sundstrand Concept Spacesuit for Advanced Planetary Exploration. John walked around outside until the weather suddenly degraded and turned into a wet, heavy snow with high winds. As luck would have it, as soon as John was taken out of the suit, we had a burst of sunlight and things seemed to dry up. John Parnell has been collecting samples of plant life in the crater, including Arctic Willow shrubs and cyanobacterial mats. Previous analyses of organic molecules in rocks in the crater have been contaminated by plant life, ie. they are a mixture of geological and biological components. By analyzing pure samples of plant life, we will be able to "subtract" their composition from the mixed analyses and so isolate the geological signature. The geological data will give us an idea of the degree to which organic molecules (a proxy for microbial life) survived the impact at varying distances from the crater's center. On Mars, where the planetary surface is heavily cratered, this kind of data will help us assess if life could survive the repeated impacts. |