Search Publications
Outgassing-induced effects in the rotational state of comet 67P/Churyumov—Gerasimenko during the Rosetta mission
Samarasinha, Nalin H.; Lamy, Philippe; Jorda, Laurent +1 more
The new target of the Rosetta mission is comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G). In order to support the planning of the mission, in particular the strategy during the mapping and landing phases, we have performed numerical simulations of the rotational evolution of a comet in the orbit of 67P/C-G. In these simulations, the currently …
Further evidence for a merger in Abell 2218 from an XMM-Newton observation
Finoguenov, A.; Böhringer, H.; Pratt, G. W.
The galaxy cluster Abell 2218, at z=0.171, is well-known for the discrepancy between mass estimates derived from X-ray and strong lensing analyses. With the present XMM-Newton observation, we are able to trace the gas density and temperature profiles out to a radius of ∼ 1400~h70-1 kpc (approximately the virial radius of the …
ISO observations of the Galactic center interstellar medium. Ionized gas
Rodríguez-Fernández, N. J.; Martín-Pintado, J.
We present fine structure and recombination line observations of the ionized gas toward a sample of 18 sources located within 300 pc of the center of the Galaxy (hereafter Galactic center, GC). The sources were selected as molecular clouds located far from thermal continuum sources. The fine structure lines from [NII] and [SIII] were detected in 1…
Deep Near-Infrared Imaging and Photometry of the Antennae Galaxies with WIRC
Hayward, T. L.; Houck, J. R.; Brandl, B. R. +6 more
We present deep near-infrared images of the Antennae galaxies, taken with the Palomar Wide-Field Infrared Camera (WIRC). The images cover a 4.33 arcmin ×4.33 arcmin (24.7×24.7 kpc) area around the galaxy interaction zone. We derive J- and Ks-band photometric fluxes for 172 infrared star clusters and discuss details of the two galactic n…
Evidence of Enceladus and Tethys microsignatures
Livi, S.; Krupp, N.; Woch, J. +7 more
We present evidence of two icy satellite microsignatures in the Cassini LEMMS data. Just upstream of Enceladus, a deep and narrow decrease in the flux of several MeV electrons is consistent with a recent absorption by that moon. This microsignature is collocated with a deep depletion in the MeV proton flux. The proton feature is much wider than th…
Planetary science: Huygens rediscovers Titan
Owen, Tobias
The first analyses of data sent by the Huygens probe from Saturn's largest moon Titan are flooding in. They paint a picture of a `Peter Pan' world - potentially like Earth, but with its development frozen at an early stage.
Effect of a Converging Flow at the Streamer Cusp on the Genesis of the Slow Solar Wind
Lapenta, Giovanni; Knoll, D. A.
The observation by the Large Angle and Spectrometric Coronagraph (LASCO) instrument on the Solar and Heliospheric Observatory of blobs of plasma generated near the cusp region of the streamer belt has sparked the hope of gaining new insight into the genesis of the slow solar wind. The observations suggest that open and closed field lines reconnect…
Cassini CIRS Observations of a Roll-Off in Saturn Ring Spectra at Submillimeter Wavelengths
Edgington, S. G.; Spilker, L. J.; Pilorz, S. H. +4 more
The Cassini Composite Infrared Spectrometer (CIRS) spatially resolved Saturn's main rings in the far-infrared, measuring the spectrum from 20 to 400 wavenumbers (cm‑1) (tens of microns to submillimeter wavelengths). We find a spectral roll-off below 50 cm‑1 (200 µm) for each of the A, B and C rings. From these data we d…
Mesoscale flows in large aspect ratio simulations of turbulent compressible convection
Rieutord, M.; Rincon, F.; Lignières, F.
We present the results of a very large aspect ratio (A=42.6) numerical simulation of fully compressible turbulent convection in a polytropic atmosphere, and focus on the properties of large-scale flows. Mesoscale patterns dominate the turbulent energy spectrum. We show that these structures, which had already been observed in Boussinesq simulation…
A Statistical Study of the Correlation between Magnetic Helicity Injection and Soft X-Ray Activity in Solar Active Regions
Kusano, K.; Sakurai, T.; Yokoyama, T. +1 more
The correlation between magnetic helicity injection across the photosphere and soft X-ray activity in the solar corona is statistically investigated for seven active regions appearing in the years 1997-2000. The magnetic helicity flux into the solar corona is analyzed by the induction equation method, using magnetograms observed by the Michelson D…