27 research outputs found
Development of the RANCOR Rotary-Percussive Coring System for Mars Sample Return
A RANCOR drill was designed to fit a Mars Exploration Rover (MER) class vehicle. The low mass of 3 kg was achieved by using the same actuator for three functions: rotation, percussions, and core break-off. Initial testing of the drill exposed an unexpected behavior of an off-the-shelf sprag clutch used to couple and decouple rotary-percussive function from the core break off function. Failure of the sprag was due to the vibration induced during percussive drilling. The sprag clutch would back drive in conditions where it was expected to hold position. Although this did not affect the performance of the drill, it nevertheless reduced the quality of the cores produced. Ultimately, the sprag clutch was replaced with a custom ratchet system that allowed for some angular displacement without advancing in either direction. Replacing the sprag with the ratchet improved the collected core quality. Also, premature failure of a 300-series stainless steel percussion spring was observed. The 300-series percussion spring was ultimately replaced with a music wire spring based on performances of previously designed rotary-percussive drill systems
The Petrochemistry of Jake_M: A Martian Mugearite
“Jake_M,” the first rock analyzed by the Alpha Particle X-ray Spectrometer instrument on the Curiosity rover, differs substantially in chemical composition from other known martian igneous rocks: It is alkaline (>15% normative nepheline) and relatively fractionated. Jake_M is compositionally similar to terrestrial mugearites, a rock type typically found at ocean islands and continental rifts. By analogy with these comparable terrestrial rocks, Jake_M could have been produced by extensive fractional crystallization of a primary alkaline or transitional magma at elevated pressure, with or without elevated water contents. The discovery of Jake_M suggests that alkaline magmas may be more abundant on Mars than on Earth and that Curiosity could encounter even more fractionated alkaline rocks (for example, phonolites and trachytes).</jats:p
Mars’ Surface Radiation Environment Measured with the Mars Science Laboratory’s Curiosity Rover
The Radiation Assessment Detector (RAD) on the Mars Science Laboratory’s Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.</jats:p
Operating the Rock Abrasion Tool (RAT) After Thirteen Years of an Originally Ninety Day Mission
Asteroids: Anchoring and Sample Acquisition Approaches in Support of Science, Exploration, and In situ Resource Utilization
Operations of the Sample Analysis at Mars instrument suite onboard the Curiosity rover
International audienceThe Sample  Analysis  at  Mars instrument  suite,  onboard  the  Curiosity  rover,  has  been analyzing  the  martian  environment  since  August  05th 2012,  as  one  of  the  main  tools  of  the Mars   Science   Laboratory mission.This   suite   is   composed   of   three   independent   but interoperable  instruments,  namely  a  Quadrupole  Mass  Spectrometer,  a Tunable  Laser Spectrometer and a Gas Chromatograph, plus a sophisticated Sample Manipulation System. SAM is used to analyze soils, rocks and atmosphere. For instance, it detected in situ martian complex   organics   for   the   first  time,   provide   us   with   a   several   years   survey   of  the atmospheric  composition  and  helped  understand  how  the  martian  environment  evolved through  the planet  history.  At  40  kg,  it  represents  half  of  the  scientific  payload  weight  of Curiosity and is one of the two analytical instruments of the mission. This instrument suite is the result of an international collaboration between the NASA Goddard Space Flight Center,  the NASA Jet Propulsion Laboratory and a consortium of French laboratories supported by the  Center  National  d’Études  Spatiales  (the French space  agency).This  contribution  will present  the  organization  of  the  SAM operational  workflow  from  the ground  infrastructure, to  flight operations  andlaboratory  supporting  work.  It  will  also  describe how  the  CNES  hosts and supports the SAM team during this exciting mission
AOAC SMPR 2014.005 Biotin in infant formula and adult/pediatric nutritional formula
Intended Use: Reference Method for dispute resolution. 1 Applicability determination: of total biotin in all forms of infant, adult, and/or pediatric formula (powders, ready-to-feed liquids, and liquid concentrates). 2 Analytical technique: any analytical technique that meets the following method performance requirements is acceptable
Science Goals and Mission Concept for a Landed Investigation of Mercury
Abstract
               Mercury holds valuable clues to the distribution of elements at the birth of the solar system and how planets form and evolve in close proximity to their host stars. This Mercury Lander mission concept returns in situ measurements that address fundamental science questions raised by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission’s pioneering exploration of Mercury. Such measurements are needed to understand Mercury's unique mineralogy and geochemistry, characterize the proportionally massive core's structure, measure the planet's active and ancient magnetic fields at the surface, investigate the processes that alter the surface and produce the exosphere, and provide ground truth for remote data sets. The mission concept achieves one full Mercury year (∼88 Earth days) of surface operations with an 11-instrument, high-heritage payload delivered to a landing site within Mercury's widely distributed low-reflectance material, and it addresses science goals encompassing geochemistry, geophysics, the Mercury space environment, and geology. The spacecraft launches in 2035, and the four-stage flight system uses a solar electric propulsion cruise stage to reach Mercury in 2045. Landing is at dusk to meet thermal requirements, permitting ∼30 hr of sunlight for initial observations. The radioisotope-powered lander continues operations through the Mercury night. Direct-to-Earth communication is possible for the initial 3 weeks of landed operations, drops out for 6 weeks, and resumes for the final month. Thermal conditions exceed lander operating temperatures shortly after sunrise, ending operations. Approximately 11 GB of data are returned to Earth. The cost estimate demonstrates that a Mercury Lander mission is feasible and compelling as a New Frontiers–class mission.</jats:p
