Expedition Objectives

Our goal is to understand the physical, chemical, geological, and climatic constraints on habitability in the high altitude lakes, and develop models (both qualitative and quantitative) for the analogy to ancient Martian lakes and for their potential for life. To reach that goal, we explore and dive in some of the highest lakes in the world as they offer the best terrestrial analogy to ancient martian lacustrine environments. Methods and techniques established for the study of Licancabur will be used this year for Poquentica and its surrounding lagunas.

Working and diving at close to 20,000 ft can be a challenge with the combination of altitude, low temperature, high winds up to 100 km/hr (60 mph), and cold water environment. The team will acclimatize for two days at 2,400 m (8,000 ft), and eight days at 4,430 m (~14,700 ft) at base camp at the foot of the Licancabur volcano. After this period of acclimatization, the ascent towards the Licancabur summit lake will begin. The team will sleep one night at camp 1 (5,000 m / 18,000 ft) and then spend 4 nights and 3 days at the summit camp (5,900 m / ~18,900 ft). After the team’s return from the summit, two days will be used to pack equipment and wrap up science. The long journey north through the altiplano will then start. It will take the team 6 days across the Andes to traverse the 700 kilometers that separate Licancabur from Poquentica. This journey will be punctuated by stops at lakes, hydrothermal springs, geothermal centers for sampling and surveys all located between 4,000 m (13,120 ft) and 4,500 m (14,760 ft). Upon arrival at Julo, near the base of Poquentica, the team will deploy again and separate into two groups, one studying the lakes at the base of the volcanic center, the other hiking up to the top of the volcano and studying life in the summit lake at 5,850 m (19,194 ft). If weather permits, the 2005 expedition should bring back an unprecedented harvest of astrobiological data on extreme lakes. Objectives include:

1. Document the impact of rapid climate change on lake habitats in Laguna Blanca and Laguna Verde through the study of the fossil stromatolites located on the paleoshores. These two lagunas were a single lake at the end of the Last Glacial Maximum (~18,000 years ago) and lost 45 m in the past 8,000 years. Changes in habitats and species are recorded in the stratigraphic column; these changes will be compared with the current environment through sample analysis and modeling of lake chemistry.
2. Complete the first-ever bathymetry and surface temperature map of the Licancabur and Poquentica summit lakes using a new, unique remote system developed by the team, which carries sonar, thermal sensors, and GPS.
3. Characterize the microbial ecology and geology at the Licancabur and Poquentica summit lakes and all the lagunas encountered on the journey through the altiplano. The team will be diving in the Licancabur summit lake, and if possible Poquentica, collecting samples of microbial organisms and lake mud;
4. Characterize the chemical, physical environment of life in all the surveyed lakes by performing in situ measurements of water chemistry and sampling for laboratory analysis; the physical environment (solar UV, PAR radiation and meteorology) will be studied by retrieving data from a network of environmental sensors positioned in the field by the team during previous expeditions;
5. Study the impact of high-UV radiation on life;
6. Document the microbial community and diversity at the lakes, searching for new extremophiles, making an attempt to better understand how organisms adapt to and survive in a range of environmental extremes;
7. Develop and maintain a daily Education and Publication Outreach (E/PO) website (http://www.eventscope.org/highlakes) during the expedition that will allow the general public, children and students to follow the scientific investigation as it unfolds and share the excitement of exploration and discovery. A daily summary in French will be also posted on the website of the French Chapter of the Mars Society at http://www.planete-mars.com.