ALBERT

Description: This paper describes the results of a recent (July-August 2010 and July 2011) planetary surface traverse planning experiment. The purpose of this experiment was to gather data relevant to robotically repositioning surface assets used for planetary surface exploration. This is a scenario currently being considered for future human exploration missions to the Moon and Mars. The specific scenario selected was a robotic traverse on the lunar surface from an outpost at Shackleton Crater to the Malapert Massif. As these are exploration scenarios, the route will not have been previously traversed and the only pre-traverse data sets available will be remote (orbital) observations. Devon Island was selected as an analog location where a traverse route of significant length could be planned and then traveled. During the first half of 2010, a team of engineers and scientists who had never been to Devon Island used remote sensing data comparable to that which is likely to be available for the Malapert region (eg., 2-meter/pixel imagery, 10-meter interval topographic maps and associated digital elevation models, etc.) to plan a 17-kilometer (km) traverse. Surface-level imagery data was then gathered on-site that was provided to the planning team. This team then assessed whether the route was actually traversable or not. Lessons learned during the 2010 experiment were then used in a second experiment in 2011 for which a much longer traverse (85 km) was planned and additional surface-level imagery different from that gathered in 2010 was obtained for a comparative analysis. This paper will describe the route planning techniques used, the data sets available to the route planners and the lessons learned from the two traverses planned and carried out on Devon Island.

Description: This paper describes NASA s current plans for the exploration of Mars by human crews within NASA s Capability-Driven Framework (CDF). The CDF describes an approach for progressively extending human explorers farther into the Solar System for longer periods of time as allowed by developments in technology and spacecraft systems. Within this framework, Mars defines the most challenging objective currently envisioned for human spaceflight. The paper first describes the CDF and potential destinations being considered within this framework. For destinations relevant to the exploration of Mars, this includes both the Martian surface and the two moons of Mars. This is followed by a brief review of our evolving understanding of Mars to provide the context for the specific objectives set for human exploration crews. This includes results from robotic missions and goals set for future Martian exploration by NASA's community-based forum, the Mars Exploration Program Analysis Group (MEPAG) and the MEPAG-sponsored Human Exploration of Mars - Science Analysis Group (HEM-SAG). The paper then reviews options available for human crews to reach Mars and return to Earth. This includes a discussion of the rationale used to select from among these options for envisioned Mars exploration missions. The paper then concludes with a description of technological and operational challenges that still face NASA in order to be able to achieve the exploration goals for Mars within the CDF.

Description: A very simple technique has been developed to converge statistical equilibrium and model atmospheric calculations in extreme non-LTE conditions when the usual iterative methods fail to converge from an LTE starting model. The proposed technique is based on a smooth transition from a collision-dominated LTE situation to the desired non-LTE conditions in which radiation dominates, at least in the most important transitions. The proposed approach was used to successfully compute stellar models with He abundances of 0.20, 0.30, and 0.50; Teff = 30,000 K, and log g = 2.9.