ESA Science & Technology - Publication Archive
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In addition, the scientific community requirements are more and more challenging: demanding mission objectives lead to more complex mission concepts. Moreover, a quicker response time from approval to launch would be desirable, whilst keeping a very high overall level of reliability.
The main objective of this study is to review the application of recurring service modules as a potential answer to the challenges listed above.
The ESA Concurrent Design Facility (CDF) was requested and financed by ESA/ESTEC/SCIAM to carry out a feasibility study for an optical-near-infrared wide field imager (WFI). Such a mission would search for Type Ia supernovae over a given redshift range with optical and near infrared wavelength coverage. The overall aim of the mission would be to use supernova observations to model the changing rate of expansion of the universe and to determine the contributions of decelerating and accelerating energies such as the mass density and dark energy density. This model could be constructed using a Hubble diagram (redshift vs. magnitude) populated with supernovae measurements. This study is the first step in the feasibility assessment of a technology reference mission and a follow-on phase-A industrial study is foreseen for the payload, where most of the technology development is needed.
We present the first set of XMM-Newton EPIC observations in the 2 square degree COSMOS field. The strength of the COSMOS project is the unprecedented combination of a large solid angle and sensitivity over the whole multiwavelength spectrum. The XMM-Newton observations are very efficient in localizing and identifying active galactic nuclei (AGN) and clusters as well as groups of galaxies. One of the primary goals of the XMM-Newton Cosmos survey is to study the co-evolution of active galactic nuclei as a function of their environment in the Cosmic web. Here we present the log of observations, images and a summary of first research highlights for the first pass of 25 XMM-Newton pointings across the field. In the existing dataset we have detected 1416 new X-ray sources in the 0.5-2, 2-4.5 and 4.5-10 keV bands to an equivalent 0.5-2 keV flux limit of 7x10-16 erg cm-2 s-1. The number of sources is expected to grow to almost 2000 in the final coverage of the survey. From an X-ray color color analysis we identify a population of heavily obscured, partially leaky or reflecting absorbers, most of which are likely to be nearby, Compton-thick AGN.
Chronology is the key to understanding climatically and tectonically driven changes on Mars. The objective of the present proposal was to assess the potential of in-situ Martian sediment dating using luminescence techniques. The work was divided into two parts:
- a) Work package 1 : Review and optimisation of appropriate techniques and instrumentation
b) Work package 2 : Laboratory measurements and proposals for instrumentation.
The aim of the activity was to develop and test an Instrumented Mole System (IMS) - i.e. a system able to deploy a mobile penetrometer carrying a payload of sensors for sub-surface measurements - to be mounted on a Planetary Lander.
This IMS could potentially be used on future planetary missions such as those for the exploration of the surface of Mercury or on other planets.
Context: In 2004 asteroid (2867) Steins has been selected as a flyby target for the Rosetta mission. Determination of its spin period and the orientation of its rotation axis are essential for optimization of the flyby planning.
Aims: Measurement of the rotation period and light curve of asteroid (2867) Steins at a phase angle larger than achievable from ground based observations, providing a high quality data set to contribute to the determination of the orientation of the spin axis and of the pole direction.
Methods: On March 11, 2006, asteroid (2867) Steins was observed continuously for 24 h with the scientific camera system OSIRIS onboard Rosetta. The phase angle was 41.7 degrees, larger than the maximum phase angle of 30 degrees when Steins is observed from Earth. A total of 238 images, covering four rotation periods without interruption, were acquired.
Results: The light curve of (2867) Steins is double peaked with an amplitude of 0.23 mag. The rotation period is 6.052 +- 0.007 h. The continuous observations over four rotation periods exclude the possibility of period ambiguities. There is no indication of deviation from a principal axis rotation state. Assuming a slope parameter of G = 0.15, the absolute visual magnitude of Steins is 13.05 +/- 0.03.