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1.
Adv Space Res ; 60(5): 1080-1100, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33162637

RESUMEN

A conceptual design is presented for a low complexity, heritage-based flyby mission to Io, Jupiter's innermost Galilean satellite and the most volcanically active body in the Solar System. The design addresses the 2011 Decadal Surveys recommendation for a New Frontiers class mission to Io and is based upon the result of the June 2012 NASA-JPL Planetary Science Summer School. A science payload is proposed to investigate the link between the structure of Io's interior, it's volcanic activity, it's surface composition, and it's tectonics. A study of Io's atmospheric processes and Io's role in the Jovian magnetosphere is also planned. The instrument suite includes a visible/near IR imager, a magnetic field and plasma suite, a dust analyzer and a gimbaled high gain antenna to perform radio science investigations. Payload activity and spacecraft operations would be powered by three Advanced Stirling Radioisotope Generators (ASRG). The primary mission includes 10 flybys with close-encounter altitudes as low as 100 km. The mission risks are mitigated by ensuring that relevant components are radiation tolerant and by using redundancy and flight-proven parts in the design. The spacecraft would be launched on an Atlas V rocket with a delta-v of 1.3 km/s. Three gravity assists (Venus, Earth, Earth) would be used to reach the Jupiter system in a 6-year cruise. The resulting concept demonstrates the rich scientific return of a flyby mission to Io.

2.
Front Res Metr Anal ; 5: 628703, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33870066

RESUMEN

Many academic analyses of good practice in the use of bibliometric data address only technical aspects and fail to account for and appreciate user requirements, expectations, and actual practice. Bibliometric indicators are rarely the only evidence put before any user group. In the present state of knowledge, it is more important to consider how quantitative evaluation can be made simple, transparent, and readily understood than it is to focus unduly on precision, accuracy, or scholarly notions of purity. We discuss how the interpretation of 'performance' from a presentation using accurate but summary bibliometrics can change when iterative deconstruction and visualization of the same dataset is applied. From the perspective of a research manager with limited resources, investment decisions can easily go awry at governmental, funding program, and institutional levels. By exploring select real-life data samples we also show how the specific composition of each dataset can influence interpretive outcomes.

3.
Nat Commun ; 7: 13161, 2016 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-27762265

RESUMEN

The Schrödinger basin on the lunar farside is ∼320 km in diameter and the best-preserved peak-ring basin of its size in the Earth-Moon system. Here we present spectral and photogeologic analyses of data from the Moon Mineralogy Mapper instrument on the Chandrayaan-1 spacecraft and the Lunar Reconnaissance Orbiter Camera (LROC) on the LRO spacecraft, which indicates the peak ring is composed of anorthositic, noritic and troctolitic lithologies that were juxtaposed by several cross-cutting faults during peak-ring formation. Hydrocode simulations indicate the lithologies were uplifted from depths up to 30 km, representing the crust of the lunar farside. Through combining geological and remote-sensing observations with numerical modelling, we show that a Displaced Structural Uplift model is best for peak rings, including that in the K-T Chicxulub impact crater on Earth. These results may help guide sample selection in lunar sample return missions that are being studied for the multi-agency International Space Exploration Coordination Group.

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