Author
J. Gil Fernandez
Bio: J. Gil Fernandez is an academic researcher from European Space Research and Technology Centre. The author has contributed to research in topics: Navigation system & Robotics. The author has an hindex of 2, co-authored 2 publications receiving 60 citations.
Topics: Navigation system, Robotics, Regolith, Asteroid, Near-Earth object
Papers
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University of Grenoble1, Université Paris-Saclay2, University of Arizona3, Arizona State University4, California Institute of Technology5, German Aerospace Center6, Centre National D'Etudes Spatiales7, University of Trento8, European Space Research and Technology Centre9, European Space Agency10, Centre national de la recherche scientifique11, Peking University12, Dresden University of Technology13, Aix-Marseille University14, Open University15, University of Southern California16, Royal Observatory of Belgium17, Tohoku University18, Space Research Centre19, Hoffmann-La Roche20, University of Toulouse21, University of Paris22, Institut supérieur de l'aéronautique et de l'espace23, Uppsala University24
TL;DR: In this paper, the authors review the requirements and model dielectric properties of asteroids to outline a possible instrument suite, and highlight the capabilities of radar instrumentation to achieve these observations.
75 citations
TL;DR: The goal of the activity has been to investigate and mature the complex couplings between the different control systems for autonomous rigid capture between an active chaser vehicle and a cooperative/non-cooperative target, and derive the required algorithms and perform a HW-in-the-loop end-to-end demonstration.
19 citations
Cited by
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TL;DR: An overview of the active space debris removal methods that are currently in development is given, which brings a huge opportunity in the area, which includes discovering commercially viable options, cleaning orbital regions, and optimizing crowded satellite orbits.
150 citations
Max Planck Society1, Johns Hopkins University Applied Physics Laboratory2, European Space Research and Technology Centre3, Aalto University4, Academy of Sciences of the Czech Republic5, Finnish Geodetic Institute6, VTT Technical Research Centre of Finland7, Spacelabs Healthcare8, Institut supérieur de l'aéronautique et de l'espace9, Aristotle University of Thessaloniki10, German Aerospace Center11, Royal Observatory of Belgium12
TL;DR: Hera will investigate the smallest asteroid visited so far, providing a unique opportunity to shed light on the role cohesion and Van der Waals forces may play in the formation and resulting internal structure of such small bodies.
134 citations
TL;DR: The Asteroid Impact & Deflection Assessment (AIDA) mission is an international cooperation between NASA and ESA as discussed by the authors, which aims to demonstrate the kinetic impact technique on a potentially hazardous near-Earth asteroid and to measure and characterize the deflection caused by the impact.
134 citations
TL;DR: In this paper, the authors reviewed the estimates of the dust-to-gas and refractory-toice mass ratios derived from Rosetta measurements in the lost materials and the nucleus of 67P/Churyumov-Gerasimenko, respectively.
Abstract: This chapter reviews the estimates of the dust-to-gas and refractory-to-ice mass ratios derived from Rosetta measurements in the lost materials and the nucleus of 67P/Churyumov-Gerasimenko, respectively. First, the measurements by Rosetta instruments are described, as well as relevant characteristics of 67P. The complex picture of the activity of 67P, with its extreme North-South seasonal asymmetry, is presented. Individual estimates of the dust-to-gas and refractory-to-ice mass ratios are then presented and compared, showing wide ranges of plausible values. Rosetta’s wealth of information suggests that estimates of the dust-to-gas mass ratio made in cometary comae at a single point in time may not be fully representative of the refractory-to-ice mass ratio within the cometary nuclei being observed.
76 citations
Arizona State University1, University of Arizona2, Jet Propulsion Laboratory3, Massachusetts Institute of Technology4, Southwest Research Institute5, Johns Hopkins University Applied Physics Laboratory6, Smithsonian Institution7, Planetary Science Institute8, University of California, Los Angeles9, Stanford University10, Centre national de la recherche scientifique11
TL;DR: Observations of Psyche with data from meteorites and models for planetesimal formation are combined to produce the best current hypotheses for Psyche's properties and provenance.
Abstract: Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.
70 citations