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Lofgren, Gary

Publications and source records attributed to Lofgren, Gary.

Desert Research and Technology Studies (DRATS) 2010 Science Operations: Operational Approaches and Lessons Learned for Managing Science during Human Planetary Surface Missions

Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona on the San Francisco Volcanic Field. These activities are designed to exercise planetary surface hardware and operations in conditions where long-distance, multi-day roving is achievable, and they allow NASA to evaluate different mission concepts and approaches in an environment less costly and more forgiving than space.The results from the RATS tests allows election of potential operational approaches to planetary surface exploration prior to making commitments to specific flight and mission hardware development. In previous RATS operations, the Science Support Room has operated largely in an advisory role, an approach that was driven by the need to provide a loose science mission framework that would underpin the engineering tests. However, the extensive nature of the traverse operations for 2010 expanded the role of the science operations and tested specific operational approaches. Science mission operations approaches from the Apollo and Mars-Phoenix missions were merged to become the baseline for this test. Six days of traverse operations were conducted during each week of the 2-week test, with three traverse days each week conducted with voice and data communications continuously available, and three traverse days conducted with only two 1-hour communications periods per day. Within this framework, the team evaluated integrated science operations management using real-time, tactical science operations to oversee daily crew activities, and strategic level evaluations of science data and daily traverse results during a post-traverse planning shift. During continuous communications, both tactical and strategic teams were employed. On days when communications were reduced to only two communications periods per day, only a strategic team was employed. The Science Operations Team found that, if communications are good and down-linking of science data is ensured, high quality science returns is possible regardless of communications. What is absent from reduced communications is the scientific interaction between the crew on the planet and the scientists on the ground. These scientific interactions were a critical part of the science process and significantly improved mission science return over reduced communications conditions. The test also showed that the quality of science return is not measurable by simple numerical quantities but is, in fact, based on strongly non-quantifiable factors, such as the interactions between the crew and the Science Operations Teams. Although the metric evaluation data suggested some trends, there was not sufficient granularity in the data or specificity in the metrics to allow those trends to be understood on numerical data alone.

Eppler, Dean↗

Geologic Traverse Planning for Apollo Missions

The science on Apollo missions was overseen by the Science Working Panel (SWP), but done by multiple PIs. There were two types of science, packages like the Apollo Lunar Surface Experiment Package (ALSEP) and traverse science. Traverses were designed on Earth for the astronauts to execute. These were under direction of the Lunar Surface PI, but the agreed traverse was a cooperation between the PI and SWP. The landing sites were selected by a different designated committee, not the SWP, and were based on science and safety.

Lofgren, Gary↗

The Traverse Planning Process for the Drats 2010 Analog Field Simulations

Traverse planning concentrates on optimizing the science return within the overall objectives of planetary surface missions or their analog field simulations. Such simulations were conducted in the San Francisco Volcanic Field, northern Arizona, from Aug. 26 to Sept 17, 2010 and involved some 200 individuals in the field, with some 40 geoscientists composing the science team. The purpose of these Desert Research and Technology Studies (DRATS) is to exercise and evaluate developmental hardware, software and operational concepts in a mission-like, fully-integrated, setting under the direction of an onsite Mobile Mission Control Center(MMCC). DRATS 2010 focused on the simultaneous operation of 2 rovers, a historic first. Each vehicle was manned by an astronaut-commander and an experienced field geologist. Having 2 rovers and crews in the field mandated substantially more complex science and mission control operations compared to the single rover DRATS tests of 2008 and 2009, or the Apollo lunar missions. For instance, the science support function was distributed over 2 "back rooms", one for each rover, with both "tactical" teams operating independently and simultaneously during the actual traverses. Synthesis and integration of the daily findings and forward planning for the next day(s) was accomplished overnight by yet another "strategic" science team.

Horz, Friedrich↗

Curating NASA's Extraterrestrial Samples - Past, Present, and Future

Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. The Astromaterials Acquisition and Curation Office at the NASA Johnson Space Center (JSC) is responsible for curating NASA s extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10E "Curation of Extraterrestrial Materials", JSC is charged with ". . . curation of all extraterrestrial material under NASA control, including future NASA missions." The Directive goes on to define Curation as including "documentation, preservation, preparation, and distribution of samples for research, education, and public outreach."

Allen, Carlton↗

Integration of Apollo Lunar Sample Data into Google Moon

The Google Moon Apollo Lunar Sample Data Integration project is a continuation of the Apollo 15 Google Moon Add-On project, which provides a scientific and educational tool for the study of the Moon and its geologic features. The main goal of this project is to provide a user-friendly interface for an interactive and educational outreach and learning tool for the Apollo missions. Specifically, this project?s focus is the dissemination of information about the lunar samples collected during the Apollo missions by providing any additional information needed to enhance the Apollo mission data on Google Moon. Apollo missions 15 and 16 were chosen to be completed first due to the availability of digitized lunar sample photographs and the amount of media associated with these missions. The user will be able to learn about the lunar samples collected in these Apollo missions, as well as see videos, pictures, and 360 degree panoramas of the lunar surface depicting the lunar samples in their natural state, following collection and during processing at NASA. Once completed, these interactive data layers will be submitted for inclusion into the Apollo 15 and 16 missions on Google Moon.

Dawson, Melissa D.↗

Curating NASA's Extraterrestrial Samples - Past, Present, and Future

Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. The Astromaterials Acquisition and Curation Office at the NASA Johnson Space Center (JSC) is responsible for curating NASA's extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10E "Curation of Extraterrestrial Materials," JSC is charged with ". . . curation of all extraterrestrial material under NASA control, including future NASA missions." The Directive goes on to define Curation as including documentation, preservation, preparation, and distribution of samples for research, education, and public outreach.

Allen, Carlton↗

Dynamic crystallization study of barred olivine chondrules

The 'classic' barred olivine (BO) texture was defined by Donaldson (1976) as a single-plate dendrite which shares the entire chondrule with the remaining glass or subsequent crystallization products. This paper describes experiments in which BO textures were produced experimentally from two starting compositions: one modeled after the average BO chondrule composition in L-chondrites determined by Weisberg (1987), and the other after an olivine-rich composition (CH-1) studied by Lofgren (1989). It is shown that most of the textural features observed in natural BO chondrules are replicated in the experimentally produced chondrules. Several new constraints on models for the chondrule-forming process are proposed.

Lofgren, Gary↗

Dynamic crystallization of chondrule melts of porphyritic olivine composition - Textures experimental and natural

A full range of textures characteristic for porphyritic olivine chondrules was reproduced in melts of the same composition, crystallized under dynamic crystallization conditions (under controlled cooling), as determined by electron microprobe analyses. The primary differences between the natural and experimentally produced porphyritic olivine textures were the nature and the extent of matrix crystallization, which reflected the subsolidus or low-temperature cooling history. The most confining limits on the chondrule-forming process were found to be the presence of crystalline precursors for the chondrule melts and the upper temperature limit of melting.

Lofgren, Gary↗

Dynamic crystallization experiments on chondrule melts in reduced gravity

Chondrules crystallized during the earliest formational history of the solar system; and, if crystal settling and flotation are indicators of crystallization in the presence of gravity, they formed without the influence of gravity. In fact, attempts to duplicate the crystallization history of chondrules in the laboratory have met with limited success, because of the difficulty of comparing objects formed under the influence of gravity with objects that did not. These comparisons are difficult because there are several recognized features introduced by the presence of gravity and no doubt some which are not yet recognized. As a result there are several microscale and macroscale aspects of chondrule petrology which are difficult to understand quantitatively. Most of the features relate to the settling or flotation of early formed crystals. The proposed experiments are briefly described.

Lofgren, Gary↗