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Mars geodesy, rotation and gravity
Dehant, Veronique; Rosenblatt, Pascal
This review provides explanations of how geodesy, rotation and gravity can be addressed using radioscience data of an orbiter around a planet or of the lander on its surface. The planet Mars is the center of the discussion. The information one can get from orbitography and radioscience in general concerns the global static gravitational field, the…
A new determination of the INTEGRAL/IBIS point source location accuracy
Hill, A. B.; Bird, A. J.; Scaringi, S. +6 more
Aims: We determine the point source location accuracy (PSLA) of the INTEGRAL/IBIS telescope based on analysis of archival in-flight data.
Methods: Over 40 000 individual pointings (science windows) of INTEGRAL/IBIS data were analysed using the latest Off-line Science Analysis software (version 7.0). Reconstructed source positions were th…
Cepheid period-luminosity relation from the AKARI observations
Onaka, Takashi; Ita, Yoshifusa; Ngeow, Chow-Choong +3 more
In this paper, we derive the period-luminosity (P-L) relation for Large Magellanic Cloud (LMC) Cepheids based on mid-infrared AKARI observations. AKARI's Infrared Camera sources were matched to the Optical Gravitational Lensing Experiment-III (OGLE-III) LMC Cepheid catalogue. Together with the available I-band light curves from the OGLE-III catalo…
The Tolman Surface Brightness Test for the Reality of the Expansion. V. Provenance of the Test and a New Representation of the Data for Three Remote Hubble Space Telescope Galaxy Clusters
Sandage, Allan
A new reduction is made of the Hubble Space Telescope (HST) photometric data for E galaxies in three remote clusters at redshifts near z = 0.85 in search for the Tolman surface brightness (SB) signal for the reality of the expansion. Because of the strong variation of SB of such galaxies with intrinsic size, and because the Tolman test is about SB…
Suzaku Constraints on Soft and Hard Excess Emissions from Abell 2199
Fukazawa, Yasushi; Makishima, Kazuo; Nakazawa, Kazuhiro +3 more
The nearby (z = 0.03015) cluster of galaxies Abell 2199 was observed by Suzaku in X-rays, with five pointings for ∼20ks each. From the XIS data, the temperature and metal abundance profiles were derived out to ∼700 kpc (0.4 times the virial radius). Both of these quantities decrease gradually from the center to peripheries by a factor of ∼2, while…
The light curve of asteroid 2867 Steins measured by VIRTIS-M during the Rosetta fly-by
Mottola, S.; Barucci, M. A.; Erard, S. +11 more
On 5 September 2008, the Rosetta spacecraft encountered the asteroid 2867 Steins on its way to the comet 67P/Churyumov-Gerasimenko. This was the first of two planned asteroid fly-bys performed by the probe, the second fly-by being with the much larger asteroid 21 Lutetia in July 2010. The VIRTIS imaging spectrometer (IFOV 0.250 mrad, overall spect…
Preparing the Rosetta deep-space operations
Ferri, Paolo; Accomazzo, Andrea; Hubault, Armelle +3 more
The International Rosetta Mission, cornerstone of the European Space Agency Scientific Programme, was launched on 2 March 2004 on its 10 years journey towards a rendezvous with comet Churyumov-Gerasimenko. Rosetta will reach the comet nucleus in summer 2014, orbit it for about 1.5 years down to distances of a few kilometres and deliver the lander …
A Non-local Thermodynamic Equilibrium Analysis of Boron Abundances in Metal-poor Stars
Shi, Jianrong; Zhao, Gang; Tan, Kefeng
The non-local thermodynamic equilibrium (NLTE) line formation of neutral boron in the atmospheres of cool stars are investigated. Our results confirm that NLTE effects for the B I resonance lines, which are due to a combination of overionization and optical pumping effects, are most important for hot, metal-poor, and low-gravity stars; however, th…
Correlations between VIMS and RADAR data over the surface of Titan: Implications for Titan’s surface properties
Barnes, J. W.; Brown, R. H.; Clark, R. N. +22 more
We apply a multivariate statistical method to Titan data acquired by different instruments onboard the Cassini spacecraft. We have searched through Cassini/VIMS hyperspectral cubes, selecting those data with convenient viewing geometry and that overlap with Cassini/RADAR scatterometry footprints with a comparable spatial resolution. We look for co…
Can Cassini magnetic field measurements be used to find the rotation period of Saturn's interior?
Bloxham, Jeremy; Sterenborg, M. Glenn
We investigate the determination of the rotation period of Saturn's interior using magnetic field measurements from Cassini. First, we vary the rotation period and search for the period that yields the smallest rms misfit of a magnetic field model to the data. Second, we search for the period that yields the most power in the non-axisymmetric comp…