Search Publications
Stratigraphy in the Mawrth Vallis region through OMEGA, HRSC color imagery and DTM
Mangold, N.; Bibring, J. -P.; Gondet, B. +7 more
The Mawrth Vallis region contains an extensive (at least 300 km × 400 km) and thick (⩾300 m), finely layered (at meter scale), clay-rich unit detected by OMEGA. We use OMEGA, HRSC DTMs derived from stereoscopic imagery, HRSC color imagery and high resolution imagery such as MOC, CTX and HiRISE to characterize the geometry and the composition of th…
The quest for the solar g modes
Baudin, F.; García, R. A.; Provost, J. +18 more
Solar gravity modes (or g modes)—oscillations of the solar interior on which buoyancy acts as the restoring force—have the potential to provide unprecedented inference on the structure and dynamics of the solar core, inference that is not possible with the well-observed acoustic modes (or p modes). The relative high amplitude of the g-mode eigenfu…
LoCuSS: Calibrating Mass-observable Scaling Relations for Cluster Cosmology with Subaru Weak-lensing Observations
Zhang, Y. -Y.; Finoguenov, A.; Smith, G. P. +4 more
We present a joint weak-lensing/X-ray study of galaxy cluster mass-observable scaling relations motivated by the critical importance of accurate calibration of mass proxies for future X-ray missions, including eROSITA. We use a sample of 12 clusters at z ~= 0.2 that we have observed with Subaru and XMM-Newton to construct relationships between the…
Resolving debris discs in the far-infrared: Early highlights from the DEBRIS survey
Ivison, R. J.; Duchêne, G.; Dent, W. R. F. +29 more
We present results from the earliest observations of DEBRIS, a Herschel key programme to conduct a volume- and flux-limited survey for debris discs in A-type through M-type stars. PACS images (from chop/nod or scan-mode observations) at 100 and 160 µm are presented toward two A-type stars and one F-type star: β Leo, β UMa and η Corvi. All th…
A Herschel study of the properties of starless cores in the Polaris Flare dark cloud region using PACS and SPIRE
Olofsson, G.; Abergel, A.; Könyves, V. +32 more
The Polaris Flare cloud region contains a great deal of extended emission. It is at high declination and high Galactic latitude. It was previously seen strongly in IRAS Cirrus emission at 100 microns. We have detected it with both PACS and SPIRE on Herschel. We see filamentary and low-level structure. We identify the five densest cores within this…
HST/COS Observations of the Quasar HE 2347-4342: Probing the Epoch of He II Patchy Reionization at Redshifts z = 2.4-2.9
Shull, J. Michael; Danforth, Charles W.; France, Kevin +2 more
We report ultraviolet spectra of the high-redshift (z em ≈ 2.9) quasar, HE 2347 - 4342, taken by the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope. Spectra in the G130M (medium resolution, 1135-1440 Å) and G140L (low resolution, 1030-2000 Å) gratings exhibit patchy Gunn-Peterson absorption in the 303.78 Å Lyα line of H…
Stability of methane clathrate hydrates under pressure: Influence on outgassing processes of methane on Titan
Sotin, Christophe; Choukroun, Mathieu; Tobie, Gabriel +1 more
We have conducted high-pressure experiments in the H 2O-CH 4 and H 2O-CH 4-NH 3 systems in order to investigate the stability of methane clathrate hydrates, with an optical sapphire-anvil cell coupled to a Raman spectrometer for sample characterization. The results obtained confirm that three …
Cassini Finds an Oxygen-Carbon Dioxide Atmosphere at Saturn’s Icy Moon Rhea
Coates, A. J.; Tokar, R. L.; Jones, G. H. +10 more
The flyby measurements of the Cassini spacecraft at Saturn’s moon Rhea reveal a tenuous oxygen (O2)-carbon dioxide (CO2) atmosphere. The atmosphere appears to be sustained by chemical decomposition of the surface water ice under irradiation from Saturn’s magnetospheric plasma. This in situ detection of an oxidizing atmosphere…
Interplanetary Shocks Lacking Type II Radio Bursts
Kaiser, M. L.; Howard, R. A.; Gopalswamy, N. +5 more
We report on the radio-emission characteristics of 222 interplanetary (IP) shocks detected by spacecraft at Sun-Earth L1 during solar cycle 23 (1996 to 2006, inclusive). A surprisingly large fraction of the IP shocks (~34%) was radio quiet (RQ; i.e., the shocks lacked type II radio bursts). We examined the properties of coronal mass ejections (CME…
Concentric crater fill in the northern mid-latitudes of Mars: Formation processes and relationships to similar landforms of glacial origin
Head, James W.; Marchant, David R.; Levy, Joseph
Hypotheses accounting for the formation of concentric crater fill (CCF) on Mars range from ice-free processes (e.g., aeolian fill), to ice-assisted talus creep, to debris-covered glaciers. Based on analysis of new CTX and HiRISE data, we find that concentric crater fill (CCF) is a significant component of Amazonian-aged glacial landsystems on Mars…