Search Publications
Outflow activity near Hadriaca Patera, Mars: Fluid-tectonic interaction investigated with High Resolution Stereo Camera stereo data and finite element modeling
Neukum, G.; Platz, T.; Dumke, A. +3 more
We investigate the formation of the outflow channels Dao and Niger Valles near the eastern rim of the Hellas impact basin, Mars. Methods used include image and topography analysis, surface age determination, and finite element modeling. Observations show that deep depressions, source regions for Dao and Niger Valles, are located in an area of shal…
Fluid simulations of mirror constraints on proton temperature anisotropy in solar wind turbulence
Passot, T.; Sulem, P. L.; Laveder, D. +1 more
Non-resonant ion perpendicular heating by low-frequency kinetic Alfvén wave turbulence, together with the constraining effect of the mirror instability on the developing temperature anisotropy observed in the solar wind, are simulated for the first time in a self-consistent way using a fluid model retaining low-frequency kinetic effects. This mode…
Electron energetics in the Enceladus torus
Cravens, T. E.; Robertson, I. P.; Perry, M. +4 more
The inner magnetosphere of Saturn contains both neutral gas and plasma whose composition is dominated by water group ion species. This gas is distributed in a torus-shaped region located near the orbit of Enceladus. The source of this gas is the predominately water vapor plume located in the south polar region of Saturn's icy satellite Enceladus. …
AKARI Near-infrared Spectroscopic Observations of Interstellar Ices in the Edge-on Starburst Galaxy NGC 253
Oyabu, Shinki; Onaka, Takashi; Yamagishi, Mitsuyoshi +4 more
We present the spatially resolved near-infrared (2.5-5.0 µm) spectra of the edge-on starburst galaxy NGC 253 obtained with the Infrared Camera on board AKARI. Near the center of the galaxy, we clearly detect the absorption features of interstellar ices (H2O: 3.05 µm, CO2: 4.27 µm, and XCN: 4.62 µm) and…
The relationship between [O III]λ5007 Å equivalent width and obscuration in active galactic nuclei
Caccianiga, A.; Severgnini, P.
In this paper we study the relationship between the equivalent width (EW) of the [O III]λ5007 Å narrow emission line in active galactic nuclei (AGN) and the level of obscuration. To this end, we combine the results of a systematic spectral analysis, both in the optical and in the X-rays, on a statistically complete sample of ∼170 X-ray selected AG…
Multiwavelength Study on Solar and Interplanetary Origins of the Strongest Geomagnetic Storm of Solar Cycle 23
Kumar, Pankaj; Uddin, Wahab; Manoharan, P. K.
We study the solar sources of an intense geomagnetic storm of solar cycle 23 that occurred on 20 November 2003, based on ground- and space-based multiwavelength observations. The coronal mass ejections (CMEs) responsible for the above geomagnetic storm originated from the super-active region NOAA 10501. We investigate the Hα observations of the fl…
Comparison of PFS and TES observations of temperature and water vapor in the martian atmosphere
Smith, Michael D.; Formisano, Vittorio; Wolkenberg, Paulina +1 more
The interval from L s = 330° in Mars Year (MY) 26 until L s = 84° in MY 27 has been used to compare and validate measurements from the Mars Global Surveyor Thermal Emission Spectrometer (TES) and the Mars Express Planetary Fourier Spectrometer (PFS). We studied differences between atmospheric temperatures observed by the two …
The Global Context of Solar Activity During the Whole Heliosphere Interval Campaign
Plunkett, S. P.; Webb, D. F.; Mandrini, C. H. +9 more
The Whole Heliosphere Interval (WHI) was an international observing and modeling effort to characterize the 3-D interconnected "heliophysical" system during this solar minimum, centered on Carrington Rotation 2068, March 20 - April 16, 2008. During the latter half of the WHI period, the Sun presented a sunspot-free, deep solar minimum type face. B…
Evidence for paleolakes in Erythraea Fossa, Mars: Implications for an ancient hydrological cycle
Head, James W.; Fassett, Caleb I.; Buhler, Peter B. +1 more
There is now widespread agreement that the surface of Mars underwent some degree of fluvial modification, but there is not yet full understanding of its surface hydrological cycle and the nature of standing bodies of water, rivers, and precipitation that affected its surface. In this paper we explore Erythraea Fossa (31.5 W, 27.3 S), a graben adja…
Day-night asymmetries of low-energy electrons in Saturn's inner magnetosphere
Coates, A. J.; Crary, F.; Burch, J. L. +2 more
We examine the day-night asymmetry of near-equatorial low energy (12-100 eV) electron fluxes measured by Cassini from July 1, 2004 through April 1, 2010. This energy range is also known to be associated with interchange injections. The electrons are separated into field-aligned (0° to 20° and 160° to 180°) pitch angles and trapped (70° to 110°) pi…