DEADLINE MONOTONIC SCHEDULING THEORY††This work is supported, in part, by the Information Engineering Advanced Technology Programme (UK), Grant GR/F 35920/4/1/1214; and the European Space Agency (ESTEC Contract 9198/90/NL/SF).

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.

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Applicability of NGGM near-real time simulations in flood detection

Journal of Geodetic Science ◽

10.1515/jogs-2019-0011 ◽

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.

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Prisma: A New Space Mission For Stellar Physics

International Astronomical Union Colloquium ◽

10.1017/s0252921100018960 ◽

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.

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

Space Science Reviews ◽

10.1007/s11214-021-00797-9 ◽

2021 ◽

Vol 217 (1) ◽

Cited By ~ 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.

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