Search Publications
Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis
Lugaz, N.; Winslow, R. M.; Salman, T. M.
Our knowledge of the properties of coronal mass ejections (CMEs) in the inner heliosphere is constrained by the relative lack of plasma observations between the Sun and 1 AU. In this work, we present a comprehensive catalog of 47 CMEs measured in situ measurements by two or more radially aligned spacecraft (MESSENGER, Venus Express, STEREO, Wind/A…
Climatology of SO2 and UV absorber at Venus' cloud top from SPICAV-UV nadir dataset
Montmessin, Franck; Bertaux, Jean-Loup; Korablev, Oleg +6 more
Following our previous work (Marcq et al., 2013, 2011), we have updated our forward radiative transfer code and processed the whole SPICAV-UV/Venus Express nadir dataset (2006-2014) in order to retrieve SO2 abundance at cloud top - assuming a SO2 decreasing scale height of 3 km and a ratio SO/SO2 tied to 10% - as w…
Thermal structure of the Venusian atmosphere from the sub-cloud region to the mesosphere as observed by radio occultation
Tellmann, Silvia; Pätzold, Martin; Imamura, Takeshi +9 more
We present distributions of the zonal-mean temperature and static stability in the Venusian atmosphere obtained from Venus Express and Akatsuki radio occultation profiles penetrating down to an altitude of 40 km. At latitudes equatorward of 75°, static stability derived from the observed temperature profiles is consistent with previous in-situ mea…
Experimental Investigation of Oxidation of Pyroxene and Basalt: Implications for Spectroscopic Analyses of the Surface of Venus and the Ages of Lava Flows
Filiberto, J.; Cutler, K. S.; Treiman, A. H. +1 more
Alteration of basalt on the surface of Venus should be dominated by nanophase hematite and sulfate coatings, but the timescale of oxidation and how that affects spectroscopic measurements has not been extensively studied. The oxidation rate and the effect on reflectance spectroscopy are needed to constrain the age of lava flows with high emissivit…
Foreshock Bubbles at Venus: Hybrid Simulations and VEX Observations
Omidi, N.; Collinson, G.; Sibeck, D.
In the absence of a global magnetic field at Venus, its ionosphere is the obstacle to the flow of the solar wind resulting in the formation of a smaller bow shock and foreshock. Spacecraft observations and global hybrid (kinetic ions, fluid electrons) simulations have demonstrated that despite its smaller size, the foreshock at Venus has propertie…
Formation and Evolution of the Large-Scale Magnetic Fields in Venus' Ionosphere: Results From a Three Dimensional Global Multispecies MHD Model
Luhmann, Janet; Toth, Gabor; Nagy, Andrew +2 more
Large-scale magnetic fields have been observed in Venus' ionosphere by both the Pioneer Venus Orbiter (PVO) and Venus Express spacecraft. In this study, we examine the formation and evolution of the large-scale magnetic field in the Venus ionosphere using a sophisticated global multispecies Magnetohydrodynamics (MHD) model that has been developed …
The Demagnetization of the Venusian Ionosphere under Nearly Flow-aligned Interplanetary Magnetic Fields
Xu, Qi; Zhang, Tielong; Xu, Xiaojun +4 more
Previous studies suggested that the interplanetary magnetic field (IMF) has a significant influence on the Venusian-induced magnetosphere. We present observations by Venus Express under a nearly flow-aligned IMF condition to investigate the demagnetization of the Venusian ionosphere. Our results show that the magnetic barrier becomes weak and narr…
Using the "Ghost Front" to Predict the Arrival Time and Speed of CMEs at Venus and Earth
Wang, Yuming; Shen, Chenglong; Lockwood, Mike +7 more
Using in situ measurements and remote-sensing observations, we study two coronal mass ejections (CMEs) that left the Sun on 2012 June 13-14 and impacted both Venus and Earth while the planets were in close radial alignment. The two CMEs generate multiple fronts in Solar Terrestrial Relations Observatory (STEREO)/Heliospheric Imager (HI) images, wh…
Foreshock Cavities at Venus and Mars
Zhang, Tielong; Futaana, Yoshifumi; Frahm, Rudy +7 more
"Foreshock cavities" are regions of turbulent and heated solar wind plasma that form upstream of Earth's bow shock. Despite being common at Earth, none have yet been reported at other planets. Here we present a survey of events encountered by the ESA Venus Express spacecraft consistent with foreshock cavities at Venus and a case study of a foresho…
Multispectral surface emissivity from VIRTIS on Venus Express
Tsang, C. C. C.; Mueller, N. T.; Smrekar, S. E.
The surface composition of Venus is mostly inaccessible to remote observation due to the dense cloud cover. There are five spectral windows that show measurable thermal emission from the surface at night. The VIRTIS spectrometer on Venus Express observed three of these windows over much of the southern hemisphere of Venus. We use these data along …