Search Publications
Ensemble Modeling of CMEs Using the WSA-ENLIL+Cone Model
Jian, L. K.; Odstrcil, D.; Zheng, Y. +8 more
Ensemble modeling of coronal mass ejections (CMEs) provides a probabilistic forecast of CME arrival time that includes an estimation of arrival-time uncertainty from the spread and distribution of predictions and forecast confidence in the likelihood of CME arrival. The real-time ensemble modeling of CME propagation uses the Wang-Sheeley-Arge (WSA…
Active volcanism on Venus in the Ganiki Chasma rift zone
Head, J. W.; Ignatiev, N. I.; Basilevsky, A. T. +3 more
Venus is known to have been volcanically resurfaced in the last third of solar system history and to have undergone a significant decrease in volcanic activity a few hundred million years ago. However, fundamental questions remain: Is Venus still volcanically active today, and if so, where and in what geological and geodynamic environment? Here we…
Science objectives and performances of NOMAD, a spectrometer suite for the ExoMars TGO mission
Aoki, S.; Vandaele, A. C.; Daerden, F. +49 more
The NOMAD spectrometer suite on the ExoMars Trace Gas Orbiter will map the composition and distribution of Mars' atmospheric trace species in unprecedented detail, fulfilling many of the scientific objectives of the joint ESA-Roscosmos ExoMars Trace Gas Orbiter mission. The instrument is a combination of three channels, covering a spectral range f…
The Interaction of Venus-like, M-dwarf Planets with the Stellar Wind of Their Host Star
Gombosi, T. I.; Drake, J. J.; Glocer, A. +4 more
We study the interaction between the atmospheres of Venus-like, non-magnetized exoplanets orbiting an M-dwarf star, and the stellar wind using a multi-species MHD model. We focus our investigation on the effect of enhanced stellar wind and enhanced EUV flux as the planetary distance from the star decreases. Our simulations reveal different topolog…
VIRTIS emissivity of Alpha Regio, Venus, with implications for tessera composition
Gilmore, Martha S.; Helbert, Jörn; Mueller, Nils
The composition of Venus tessera terrain is unknown. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) aboard Venus Express (VEx) collects data that yields the surface emissivity at ∼1 µm, which contains information convolving a number of surface properties, including composition. We examine the variation of emissivity in the vi…
Radiative heating and cooling in the middle and lower atmosphere of Venus and responses to atmospheric and spectroscopic parameter variations
Kappel, D.; Arnold, G.; Haus, R.
A sophisticated radiative transfer model that considers absorption, emission, and multiple scattering by gaseous and particulate constituents over the broad spectral range 0.125-1000 µm is applied to calculate radiative fluxes and temperature change rates in the middle and lower atmosphere of Venus (0-100 km). Responses of these quantities t…
Thermal evolution of Venus with argon degassing
O'Rourke, Joseph G.; Korenaga, Jun
Decades-old measurements of atmospheric and elemental surface composition constrain the history of Venus. In this study, we search for a model featuring continuous evolution in the stagnant-lid regime that predicts the present-day atmospheric mass of radiogenic argon and satisfies the other available constraints. For comparison, we also consider t…
Propagation of the 7 January 2014 CME and Resulting Geomagnetic Non-event
Thompson, B. J.; Möstl, C.; Jian, L. K. +9 more
On 2014 January 7 an X1.2 flare and coronal mass ejection (CME) with a radial speed ≈2500 km s-1 was observed from near an active region close to disk center. This led many forecasters to estimate a rapid arrival at Earth (≈36 hr) and predict a strong geomagnetic storm. However, only a glancing CME arrival was observed at Earth with a t…
Six years of Venus winds at the upper cloud level from UV, visible and near infrared observations from VIRTIS on Venus Express
Hueso, R.; Sánchez-Lavega, A.; Peralta, J. +2 more
The Venus Express mission has provided a long-term monitoring of Venus atmosphere including the morphology and motions of its upper clouds. Several works have focused on the dynamics of the upper cloud visible on the day-side in ultraviolet images sensitive to the 65-70 km altitude and in the lower cloud level (50 km height) observable in the nigh…
Lithospheric structure of Venus from gravity and topography
Ruiz, Javier; Jiménez-Díaz, Alberto; Kirby, Jon F. +3 more
There are many fundamental and unanswered questions on the structure and evolution of the venusian lithosphere, which are key issues for understanding Venus in the context of the origin and evolution of the terrestrial planets. Here we investigate the lithospheric structure of Venus by calculating its crustal and effective elastic thicknesses (T