scholarly journals Gravitational Experimental Platform for Animal Models, a New Platform at ESA’s Terrestrial Facilities to Study the Effects of Micro- and Hypergravity on Aquatic and Rodent Animal Models

2021 ◽  
Vol 22 (6) ◽  
pp. 2961
Author(s):  
Julie Bonnefoy ◽  
Stéphanie Ghislin ◽  
Jérôme Beyrend ◽  
Florence Coste ◽  
Gaetano Calcagno ◽  
...  
Keyword(s):  
Animal Models ◽  
European Space Agency ◽  
Hindlimb Unloading ◽  
Aquatic Animal ◽  
Altered Gravity ◽  
Cellular Mechanisms ◽  
Experimental Platform ◽  
Space Agency ◽  
Space Experiments ◽  
Specific Pathogen

Using rotors to expose animals to different levels of hypergravity is an efficient means of understanding how altered gravity affects physiological functions, interactions between physiological systems and animal development. Furthermore, rotors can be used to prepare space experiments, e.g., conducting hypergravity experiments to demonstrate the feasibility of a study before its implementation and to complement inflight experiments by comparing the effects of micro- and hypergravity. In this paper, we present a new platform called the Gravitational Experimental Platform for Animal Models (GEPAM), which has been part of European Space Agency (ESA)’s portfolio of ground-based facilities since 2020, to study the effects of altered gravity on aquatic animal models (amphibian embryos/tadpoles) and mice. This platform comprises rotors for hypergravity exposure (three aquatic rotors and one rodent rotor) and models to simulate microgravity (cages for mouse hindlimb unloading and a random positioning machine (RPM)). Four species of amphibians can be used at present. All murine strains can be used and are maintained in a specific pathogen-free area. This platform is surrounded by numerous facilities for sample preparation and analysis using state-of-the-art techniques. Finally, we illustrate how GEPAM can contribute to the understanding of molecular and cellular mechanisms and the identification of countermeasures.

III. Metallurgy: The proposed French metallurgy programme for Spacelab

1978 ◽  
Vol 361 (1705) ◽  
pp. 165-174 ◽  
Keyword(s):  
Crystal Growth ◽  
Preliminary Analysis ◽  
European Space Agency ◽  
Government Agencies ◽  
Zero Gravity ◽  
Industrial Community ◽  
Space Agency ◽  
Space Experiments ◽  
The Government ◽  
High Level

The call for ideas for the first Spacelab payload issued from the European Space Agency (E.S.A.) obtained in France a fairly high level of success from the government agencies but almost no answers from the industrial community. This situation, which arose despite knowledge of some early but very promising results of the first space experiments, seems to be correlated with the absence of any guarantee about the future Law of Space, and consequently has orientated the French metallurgy experiments to more academic and less applied speculations. We shall describe the actions of the French Space Agency (C.N.E.S.) to decide which experiments would be officially supported by C.N.E.S. if accepted by E.S.A. In the particular field of metallurgy, six proposals were so selected which have been proposed to E.S.A. for the first Spacelab payload. We shall present the arguments which defended those proposals and as a function of the preliminary analysis of some similar U.S. experiments we shall try to detect some of the possible difficulties in performing them and to foresee the main results which we expect. Special emphasis will be laid on the thermodiffusion and nucleation experiments, the study of which is basic for many crystal growth or metallurgy experiments in a zero-gravity environment.

scholarly journals Detailed Modeling of Cork-Phenolic Ablators in Preparation for the Post-flight Analysis of the QARMAN Re-entry CubeSat

2021 ◽  
Author(s):  
Claudio Miccoli ◽  
Alessandro Turchi ◽  
Pierre Schrooyen ◽  
Domenic D’Ambrosio ◽  
Thierry Magin
Keyword(s):  
Fluid Dynamics ◽  
Thermal Protection ◽  
A Priori ◽  
European Space Agency ◽  
Thermal Response ◽  
Accurate Method ◽  
Navier Stokes ◽  
Advection Equation ◽  
High Enthalpy ◽  
Space Agency

AbstractThis work deals with the analysis of the cork P50, an ablative thermal protection material (TPM) used for the heat shield of the qarman Re-entry CubeSat. Developed for the European Space Agency (ESA) at the von Karman Institute (VKI) for Fluid Dynamics, qarman is a scientific demonstrator for Aerothermodynamic Research. The ability to model and predict the atypical behavior of the new cork-based materials is considered a critical research topic. Therefore, this work is motivated by the need to develop a numerical model able to respond to this demand, in preparation to the post-flight analysis of qarman. This study is focused on the main thermal response phenomena of the cork P50: pyrolysis and swelling. Pyrolysis was analyzed by means of the multi-physics Computational Fluid Dynamics (CFD) code argo, developed at Cenaero. Based on a unified flow-material solver, the Volume Averaged Navier–Stokes (VANS) equations were numerically solved to describe the interaction between a multi-species high enthalpy flow and a reactive porous medium, by means of a high-order Discontinuous Galerkin Method (DGM). Specifically, an accurate method to compute the pyrolysis production rate was implemented. The modeling of swelling was the most ambitious task, requiring the development of a physical model accounting for this phenomenon, for the purpose of a future implementation within argo. A 1D model was proposed, mainly based on an a priori assumption on the swelling velocity and the resolution of a nonlinear advection equation, by means of a Finite Difference Method (FDM). Once developed, the model was successfully tested through a matlab code, showing that the approach is promising and thus opening the way to further developments.

scholarly journals Molecular and Cellular Mechanisms Underlying Temperature-Dependent Sex Determination in Turtles

2021 ◽  
pp. 1-9
Author(s):  
Horacio Merchant-Larios ◽  
Verónica Díaz-Hernández ◽  
Diego Cortez
Keyword(s):  
Animal Models ◽  
Sex Determination ◽  
Incubation Temperature ◽  
State Of The Art ◽  
Current Understanding ◽  
Temperature Dependent ◽  
Cellular Mechanisms ◽  
Male Phenotype ◽  
History Of ◽  
Reptilian Species

The discovery in mammals that fetal testes are required in order to develop the male phenotype inspired research efforts to elucidate the mechanisms underlying gonadal sex determination and differentiation in vertebrates. A pioneer work in 1966 that demonstrated the influence of incubation temperature on sexual phenotype in some reptilian species triggered great interest in the environment’s role as a modulator of plasticity in sex determination. Several chelonian species have been used as animal models to test hypotheses concerning the mechanisms involved in temperature-dependent sex determination (TSD). This brief review intends to outline the history of scientific efforts that corroborate our current understanding of the state-of-the-art in TSD using chelonian species as a reference.

scholarly journals Applicability of NGGM near-real time simulations in flood detection

2019 ◽  
Vol 9 (1) ◽  
pp. 111-126
Author(s):  
A. F. Purkhauser ◽  
J. A. Koch ◽  
R. Pail
Keyword(s):  
European Space Agency ◽  
Earth System ◽  
The Earth ◽  
Future Mission ◽  
Space Agency ◽  
Flood Detection ◽  
The One ◽  
Real Time Simulations ◽  
Grace Mission ◽  
Gravity Mission

Abstract The GRACE mission has demonstrated a tremendous potential for observing mass changes in the Earth system from space for climate research and the observation of climate change. Future mission should on the one hand extend the already existing time series and also provide higher spatial and temporal resolution that is required to fulfil all needs placed on a future mission. To analyse the applicability of such a Next Generation Gravity Mission (NGGM) concept regarding hydrological applications, two GRACE-FO-type pairs in Bender formation are analysed. The numerical closed loop simulations with a realistic noise assumption are based on the short arc approach and make use of the Wiese approach, enabling a self-de-aliasing of high-frequency atmospheric and oceanic signals, and a NRT approach for a short latency. Numerical simulations for future gravity mission concepts are based on geophysical models, representing the time-variable gravity field. First tests regarding the usability of the hydrology component contained in the Earth System Model (ESM) by the European Space Agency (ESA) for the analysis regarding a possible flood monitoring and detection showed a clear signal in a third of the analysed flood cases. Our analysis of selected cases found that detection of floods was clearly possible with the reconstructed AOHIS/HIS signal in 20% of the tested examples, while in 40% of the cases a peak was visible but not clearly recognisable.

scholarly journals Prisma: A New Space Mission For Stellar Physics

1993 ◽  
Vol 137 ◽  
pp. 812-819
Author(s):  
T. Appourchaux ◽  
D. Gough ◽  
P. Hyoyng ◽  
C. Catala ◽  
S. Frandsen ◽  
...  
Keyword(s):  
European Space Agency ◽  
Real Space ◽  
Space Mission ◽  
Economic Conditions ◽  
X Ray ◽  
Space Agency ◽  
New Space

PRISMA (Probing Rotation and Interior of Stars: Microvariability and Activity) is a new space mission of the European Space Agency. PRISMA is currently in a Phase A study with 3 other competitors. PRISMA is the only ESA-only mission amongst those four and only one mission will be selected in Spring 1993 to become a real space mission.The goal of the Phase A study is to determine whether the payload of PRISMA can be accommodated on a second unit of the X-ray Multi-Mirror (XMM) bus; and whether the budget of the PRISMA mission can be kept below 265 MAU (’88 Economic conditions). The XMM mission is an approved cornerstone and is in a Phase A together with PRISMA.

scholarly journals BepiColombo Science Investigations During Cruise and Flybys at the Earth, Venus and Mercury

2021 ◽  
Vol 217 (1) ◽  
Author(s):  
Valeria Mangano ◽  
Melinda Dósa ◽  
Markus Fränz ◽  
Anna Milillo ◽  
Joana S. Oliveira ◽  
...  
Keyword(s):  
French Guiana ◽  
European Space Agency ◽  
Scientific Research ◽  
The Earth ◽  
Space Agency ◽  
Spacecraft Mission ◽  
Joint Mission ◽  
Science Investigations ◽  
Orbit Insertion ◽  
Inner Heliosphere

AbstractThe dual spacecraft mission BepiColombo is the first joint mission between the European Space Agency (ESA) and the Japanese Aerospace Exploration Agency (JAXA) to explore the planet Mercury. BepiColombo was launched from Kourou (French Guiana) on October 20th, 2018, in its packed configuration including two spacecraft, a transfer module, and a sunshield. BepiColombo cruise trajectory is a long journey into the inner heliosphere, and it includes one flyby of the Earth (in April 2020), two of Venus (in October 2020 and August 2021), and six of Mercury (starting from 2021), before orbit insertion in December 2025. A big part of the mission instruments will be fully operational during the mission cruise phase, allowing unprecedented investigation of the different environments that will encounter during the 7-years long cruise. The present paper reviews all the planetary flybys and some interesting cruise configurations. Additional scientific research that will emerge in the coming years is also discussed, including the instruments that can contribute.

scholarly journals Gaia Data Release 2

2018 ◽  
Vol 616 ◽  
pp. A2 ◽  
Author(s):  
L. Lindegren ◽  
J. Hernández ◽  
A. Bombrun ◽  
S. Klioner ◽  
U. Bastian ◽  
...  
Keyword(s):  
Proper Motion ◽  
Input Data ◽  
European Space Agency ◽  
Iterative Solution ◽  
Spatial Correlations ◽  
Satellite Attitude ◽  
Space Agency ◽  
Data Release ◽  
Ccd Observations ◽  
Celestial Reference System

Context. Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational phase. Aims. We describe the input data, models, and processing used for the astrometric content of Gaia DR2, and the validation of these resultsperformed within the astrometry task. Methods. Some 320 billion centroid positions from the pre-processed astrometric CCD observations were used to estimate the five astrometric parameters (positions, parallaxes, and proper motions) for 1332 million sources, and approximate positions at the reference epoch J2015.5 for an additional 361 million mostly faint sources. These data were calculated in two steps. First, the satellite attitude and the astrometric calibration parameters of the CCDs were obtained in an astrometric global iterative solution for 16 million selected sources, using about 1% of the input data. This primary solution was tied to the extragalactic International Celestial Reference System (ICRS) by means of quasars. The resulting attitude and calibration were then used to calculate the astrometric parameters of all the sources. Special validation solutions were used to characterise the random and systematic errors in parallax and proper motion. Results. For the sources with five-parameter astrometric solutions, the median uncertainty in parallax and position at the reference epoch J2015.5 is about 0.04 mas for bright (G < 14 mag) sources, 0.1 mas at G = 17 mag, and 0.7 masat G = 20 mag. In the proper motion components the corresponding uncertainties are 0.05, 0.2, and 1.2 mas yr−1, respectively.The optical reference frame defined by Gaia DR2 is aligned with ICRS and is non-rotating with respect to the quasars to within 0.15 mas yr−1. From the quasars and validation solutions we estimate that systematics in the parallaxes depending on position, magnitude, and colour are generally below 0.1 mas, but the parallaxes are on the whole too small by about 0.03 mas. Significant spatial correlations of up to 0.04 mas in parallax and 0.07 mas yr−1 in proper motion are seen on small (< 1 deg) and intermediate (20 deg) angular scales. Important statistics and information for the users of the Gaia DR2 astrometry are given in the appendices.

Thermophysical Properties of Fluids Measured Under Microgravity Conditions

1998 ◽  
Vol 551 ◽  
Author(s):  
H.-J. Fecht ◽  
R.K. Wunderlich
Keyword(s):  
Thermophysical Property ◽  
Thermophysical Properties ◽  
European Space Agency ◽  
Space Station ◽  
Space Flights ◽  
Space Agency ◽  
Property Data ◽  
Microgravity Conditions ◽  
Key Industries ◽  
Sufficient Precision

AbstractThe analysis of nucleation and growth processes relies mostly on circular arguments since basic thermophysical properties necessary, such as the Gibbs free energy (enthalpy of crystallization, specific heat), the density, emissivity, thermal conductivity (diffusivity), diffusion coefficients, surface tension, viscosity, interfacial crystal / liquid tension, etc. are generally unknown with sufficient precision and therefore often deduced from insufficient linear interpolations from the elements. The paucity of thermophysical property data for commercial materials as well as research materials is mostly a result of the experimental difficulties arising from the unwanted convection and reactions of melts with containers at high temperatures. An overview will be given on the results of thermophysical property measurements during several different space flights using containerless processing methods. Furthermore, a perspective on a future measurement program of thermophysical properties supported by the European Space Agency is described. In this regard, the International Space Station is considered as the ideal laboratory for high precision measurements of thermophysical properties of fluids which help to improve manufacturing processes for a number of key industries.

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