|
|
| ExoMars Science Management Plan |
Document reference number: EXM-MS-PL-ESA-00002
This Science Management Plan specifies in detail the scientific management of the ExoMars programme, focusing on the way the payload is selected and implemented for the various mission elements, as a joint effort of the scientific community, the funding organisations, ESA and NASA. The modes of participation in the programme are addressed, as well as the responsibility of the ESA Project Manager, Project Scientist, and their teams vis-à-vis the implementation and exploitation of the instruments. Finally, the data rights of the involved scientists and their responsibilities for the public outreach activities are explained, as is the data analysis support policy.
Once approved, the ExoMars Science Management Plan will become applicable to all parties wishing to participate in the ExoMars programme. Whenever mission or programmatic developments justify a revision, the ExoMars Science Management Plan will be updated and resubmitted, to the Advisory Bodies for endorsement and to the Programme Board (PB-HME) for approval. |
| Publication date: 12 Feb 2010 |
|
|
| Evolution of Infrared Luminosity functions of Galaxies in the AKARI NEP-Deep field. Revealing the cosmic star formation history hidden by dust |
Aims. Dust-obscured star-formation increases with increasing intensity and increasing redshift. We aim to reveal the cosmic starformation history obscured by dust using deep infrared observation with AKARI.
Methods. We constructed restframe 8 micron, 12 micron, and total infrared (TIR) luminosity functions (LFs) at 0.15 < z < 2.2 using 4128 infrared sources in the AKARI NEP-Deep field. A continuous filter coverage in the mid-IR wavelength (2.4, 3.2, 4.1, 7, 9, 11, 15, 18, and 24 micron) by the AKARI satellite allowed us to estimate restframe 8 micron and 12 micron luminosities without using a large extrapolation based on an SED fit, which was the largest uncertainty in previous work.
Results. We find that all 8 micron (0.38 < z < 2.2), 12 micron (0.15 < z < 1.16), and TIR LFs (0.2 < z < 1.6) show continuous and strong evolution toward higher redshift. Our direct estimate of 8 micron LFs is useful since previous work often had to use a large extrapolation from the Spitzer 24 micron to 8 micron, where SED modeling is more difficult because of the PAH emissions. In terms of cosmic infrared luminosity density (OmegaIR), which was obtained by integrating analytic fits to the LFs, we find good agreement with previous work at z < 1.2. We find the OmegaIR evolves as proportinal to (1 + z)4.4±1.0. When we separate contributions to OmegaIR by LIRGs and ULIRGs, we found more IR luminous sources are increasingly more important at higher redshift. We find that the ULIRG (LIRG) contribution increases by a factor of 10 (1.8) from z=0.35 to z=1.4. |
| Publication date: 05 Feb 2010 |
|
|
| Spatium 24: Cosmic Visions |
| This issue of Spatium summarizes a talk by Prof. Southwood, ESA's Director of Science and Robotic Exploration, on the European Space Agency's scientific programme: Cosmic Vision. |
| Publication date: 01 Feb 2010 |
|
|
| Correlations between cloud thickness and sub-cloud water abundance on Venus |
| Past spacecraft observations of Venus have found considerable spatial and temporal variations of water vapour abundance above the clouds. Previous searches for variability below the clouds at 30-45 km altitude found no large scale latitudinal gradients, but lacked the spatial resolution to detect smaller scale variations. Here we interpret results from the VIRTIS imaging spectrometer on Venus Express, remotely sounding at near-infrared "spectral window" wavelengths, as indicating that the water vapour abundance at 30-40 km altitude varies from 22 to 35 ppmv (±4 ppmv). Furthermore, this variability is correlated with cloud opacity, supporting the hypothesis that its genesis is linked to cloud convection. It is also possible to fit the observations without requiring spatial variation of water abundance, but this places a strong constraint on the spectral dependence of the refractive index data assumed for the lower cloud particles, for which there is as yet no supporting evidence. |
| Publication date: 26 Jan 2010 |
|
|
| Formation of Iapetus' Extreme Albedo Dichotomy by Exogenically Triggered Thermal Ice Migration |
| The extreme albedo asymmetry of Saturn's moon Iapetus, which is about 10 times as bright on its trailing hemisphere as on its leading hemisphere, has been an enigma for three centuries. Deposition of exogenic dark material on the leading side has been proposed as a cause, but this alone cannot explain the global shape, sharpness, and complexity of the transition between Iapetus' bright and dark terrain. We demonstrate that all these characteristics, and the asymmetry's large amplitude, can be plausibly explained by runaway global thermal migration of water ice, triggered by the deposition of dark material on the leading hemisphere. This mechanism is unique to Iapetus among the saturnian satellites because its slow rotation produces unusually high daytime temperatures and water ice sublimation rates for a given albedo. |
| Publication date: 22 Jan 2010 |
|
|
| Iapetus: Unique Surface Properties and a Global Color Dichotomy from Cassini Imaging |
| Since 2004, Saturn's moon Iapetus has been observed repeatedly with the Imaging Science Subsystem of the Cassini spacecraft. The images show numerous impact craters down to the resolution limit of ~10 meters per pixel. Small, bright craters within the dark hemisphere indicate a dark blanket thickness on the order of meters or less. Dark, equator-facing and bright, poleward-facing crater walls suggest temperature-driven water-ice sublimation as the process responsible for local albedo patterns. Imaging data also reveal a global color dichotomy, wherein both dark and bright materials on the leading side have a substantially redder color than the respective trailing-side materials. This global pattern indicates an exogenic origin for the redder leading-side parts and suggests that the global color dichotomy initiated the thermal formation of the global albedo dichotomy. |
| Publication date: 22 Jan 2010 |
|
|
| Star formation and dust extinction properties of local galaxies from the AKARI-GALEX all-sky surveys: First results from the most secure multiband sample from the far-ultraviolet to the far-infrared |
Aims. We explore spectral energy distributions (SEDs), star formation (SF), and dust extinction properties of galaxies in the Local Universe.
Methods. The AKARI All-Sky Survey provided the first bright point source catalog detected at 90 micron. Beginning with this catalog, we selected galaxies by matching the AKARI sources with those in the IRAS Point Source Catalog Redshift Survey. We measured the total GALEX FUV and NUV flux densities with a photometry software we specifically developed for this purpose. In a further step we matched this sample with the Sloan Digital Sky Survey (SDSS) and Two Micron All Sky Survey (2MASS) galaxies. With this procedure we obtained a basic sample which consists of 776 galaxies. After removing objects whose photometry was contaminated by foreground sources (mainly in the SDSS), we defined the "secure sample" which contains 607 galaxies.
Results. The sample galaxies have redshifts of <~ 0.15, and their 90-micron luminosities range from 106 to 1012 Lsun, with a peak at 1010 Lsun. The SEDs display a large variety, especially more than four orders of magnitude at the mid-far-infrared (M-FIR), but if we sort the sample with respect to 90 micron, the average SED shows a coherent trend: the more luminous an SED at 90 micron, the redder the global SED becomes. The Mr-NUV - r color-magnitude relation of our sample does not show bimodality, and the distribution is centered on the green valley.
- Remainder of abstract is truncated - |
| Publication date: 22 Jan 2010 |
|
|
| A weak lensing study of X-ray groups in the COSMOS survey: form and evolution of the Mass-Luminosity relation |
| Measurements of X-ray scaling laws are critical for improving cosmological constraints derived with
the halo mass function and for understanding the physical processes that govern the heating and
cooling of the intracluster medium. In this paper, we use a sample of 206 X-ray selected galaxy
groups to investigate the scaling relation between X-ray luminosity (LX) and halo mass (M200) where M200 is derived via stacked weak gravitational lensing. This work draws upon a broad array of multiwavelength
COSMOS observations including 1.64 degrees2 of contiguous imaging with the Advanced Camera for Surveys (ACS) to a limiting magnitude of IF814W = 26.5 and deep XMM-Newton/Chandra imaging to a limiting flux of 1.0 x 10-15 erg cm-2 s-1 in the 0.5-2 keV band. The combined depth of these two data-sets allows us to probe the lensing signals of X-ray detected structures at both higher redshifts and lower masses than previously explored. Weak lensing profiles and halo masses are derived for nine sub-samples, narrowly binned in luminosity and redshift. The COSMOS data alone
are well fit by a power law with a slope of alpha = 0.66 +/- 0.14. These results significantly extend the dynamic range for which the halo masses of X-ray selected structures have been measured
with weak gravitational lensing. As a result, tight constraints are obtained for the slope of the M-LX relation. The combination of our group data with previously published cluster data demonstrates that the M-LX relation is well described by a single power law, alpha = 0.64 +/- 0.03, over two decades in mass. These results are inconsistent at the 3.7 sigma level with the self-similar prediction of alpha = 0.75. We examine the redshift dependence of the M - LX relation and find little evidence for evolution beyond the rate predicted by self-similarity from z ~0.25 to z ~0.8. |
| Publication date: 20 Jan 2010 |
|
|
| BepiColombo-Comprehensive exploration of Mercury: Mission overview and science goals |
| BepiColombo is an interdisciplinary mission to explore Mercury, the planet closest to the sun, carried out jointly between the European Space Agency and the Japanese Aerospace Exploration Agency. From dedicated orbits two spacecraft will be studying the planet and its environment. The scientific payload of both spacecraft will provide the detailed information necessary to understand the origin and evolution of the planet itself and its surrounding environment. The scientific objectives focus on a global characterization of Mercury through the investigation of its interior, surface, exosphere and magnetosphere. In addition, instrumentation onboard BepiColombo will be used to test Einstein's theory of general relativity. Major effort was put into optimizing the scientific return of the mission by defining a payload complement such that individual measurements can be interrelated and complement each other. This paper gives an in-depth overview of BepiColombo spacecraft composite and the mission profile. It describes the suite of scientific instruments on board of the two BepiColombo spacecraft and the science goals of the mission. |
| Publication date: 15 Jan 2010 |
|
|
| The Cluster Active Archive - Studying the Earth's Space Plasma Environment |
Book published in the series "Astrophysics and Space Science Proceedings"; H. Laakso, M.G.G.T. Taylor, C.P. Escoubet (Eds.), 2010, XX, 489 p., Hardcover, ISBN: 978-90-481-3498-4, © Springer  Since the year 2000 the ESA Cluster mission has been investigating the small-scale structures and processes of the Earth's plasma environment, such as those involved in the interaction between the solar wind and the magnetospheric plasma, in global magnetotail dynamics, in cross-tail currents, and in the formation and dynamics of the neutral line and of plasmoids.
This book contains presentations made at the 15th Cluster workshop held in March 2008. It also presents several articles about the Cluster Active Archive and its datasets, a few overview papers on the Cluster mission, and articles reporting on scientific findings on the solar wind, the magnetosheath, the magnetopause and the magnetotail. The contents of the book are grouped into seven main parts:
- Part I - Products and Services of the Cluster Active Archive
- Part II - Tools for the CAA Data Analysis
- Part III - Measurement Techniques and Calibration Routines
- Part IV - Magnetospheric Missions
- Part V - Observations of Solar Wind and Magnetosheath
- Part VI - Observations of Magnetopause and Cusp
- Part VII - Observations of Magnetospheric Tail
|
| Publication date: 15 Jan 2010 |
|
|
| ExoMars Orbiter: Experiment Proposal Information Package (E-PIP) |
Document: EXM-OM-IPA-ESA-00001
The Experiment Proposal Information Package (E-PIP) defines all technical, managerial and
programmatic data that are relevant in the context of the Announcement of Opportunity (AO)
for the scientific instruments on the ExoMars Trace Gas Orbiter Spacecraft. It does not yet
contain formally agreed requirements, however all stated parameter values and other data
reflect the currently agreed baseline for the spacecraft, the mission, mission operations, product
assurance, and managerial approach. Also, all relevant supporting information, as far as
currently known, is contained in the E-PIP.
Following instrument selection the Experiment Interface Requirements Document (E-IRD) will
be issued to define all the technical, managerial and programmatic requirements applicable to
each scientific instrument interface with the ExoMars Trace Gas Orbiter Spacecraft and
Mission.
All instruments will have to be compliant with this E-IRD. The E-IRD shall be considered as a
baseline for the definition and update of the individual Instruments Experiment Interface
Control Document (E-ICD) relevant to each instrument through all phases of the ExoMars
Trace Gas Orbiter development. |
| Publication date: 11 Jan 2010 |
|
|
| E-Type Asteroid (2867) Steins as Imaged by OSIRIS on Board Rosetta |
| The European Space Agency's Rosetta mission encountered the main-belt asteroid (2867) Steins while on its way to rendezvous with comet 67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical, spectroscopic, and infrared remote imaging system) cameras on board Rosetta show that Steins is an oblate body with an effective spherical diameter of 5.3 kilometers. Its surface does not show colour variations. The morphology of Steins is dominated by linear faults and a large 2.1-kilometer-diameter crater near its south pole. Crater counts reveal a distinct lack of small craters. Steins is not solid rock but a rubble pile and has a conical appearance that is probably the result of reshaping due to Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) spin-up. The OSIRIS images constitute direct evidence for the YORP effect on a main-belt asteroid. |
| Publication date: 08 Jan 2010 |
|
|
