Venus Express: Scientific goals, instrumentation, and scenario of the mission

The first European mission to Venus (Venus Express) is described. It is based on a repeated use of the Mars Express design with minor modifications dictated in the main by more severe thermal environment at Venus. The main scientific task of the mission is global exploration of the Venusian atmosphere, circumplanetary plasma, and the planet surface from an orbiting spacecraft. The Venus Express payload includes seven instruments, five of which are inherited from the missions Mars Express and Rosetta. Two instruments were specially designed for Venus Express. The advantages of Venus Express in comparison with previous missions are in using advanced instrumentation and methods of remote sounding, as well as a spacecraft with a broad spectrum of capabilities of orbital observations. © Pleiades Publishing, Inc., 2006

Venus express - The first European mission to Venus

Venus Express is the first European mission to planet Venus. The mission aims at a comprehensive investigation of Venus atmosphere and plasma environment and will address some important aspects of the surface physics from orbit. In particular, Venus Express will focus on the structure, composition, and dynamics of the Venus atmosphere, escape processes and interaction of the atmosphere with the solar wind and so to provide answers to the many questions that still remain unanswered in these fields. Venus Express will enable a breakthrough in Venus science after a long period of silence since the period of intense exploration in the 1970s and the 1980s. The payload consists of seven instruments. Five of them were inherited from the Mars Express and Rosetta projects while two instruments were designed and built specifically for Venus Express. The suite of spectrometers and imaging instruments, together with the radio-science experiment, and the plasma package make up an optimised payload well capable of addressing the mission goals to sufficient depth. Several of the instruments will make specific use of the spectral windows at infrared wavelengths in order to study the atmosphere in three dimensions. The spacecraft is based on the Mars Express design with minor modifications mainly needed to cope with the thermal environment around Venus, and so a very cost-effective mission has been realised in an exceptionally short time. The spacecraft was launched on 9 November 2005 from Baikonur, Kazakhstan, by a Russian Soyuz-Fregat launcher and arrived at Venus on 11 April 2006. Venus Express will carry out observations of the planet from a highly elliptic polar orbit with a 24-h period. In 3 Earth years (4 Venus sidereal days) of operations, it will return about 2 Tbit of scientific data. Telecommunications with the Earth is performed by the new ESA ground station in Cebreros, Spain, while a nearly identical ground station in New Norcia, Australia, supports the radio-science investigations. © 2007 Elsevier Ltd. All rights reserved

Evaluation of (15)N-detected H-N correlation experiments on increasingly large RNAs.

Recently, (15)N-detected multidimensional NMR experiments have been introduced for the investigation of proteins. Utilization of the slow transverse relaxation of nitrogen nuclei in a (15)N-TROSY experiment allowed recording of high quality spectra for high molecular weight proteins, even in the absence of deuteration. Here, we demonstrate the applicability of three (15)N-detected H-N correlation experiments (TROSY, BEST-TROSY and HSQC) to RNA. With the newly established (15)N-detected BEST-TROSY experiment, which proves to be the most sensitive (15)N-detected H-N correlation experiment, spectra for five RNA molecules ranging in size from 5 to 100 kDa were recorded. These spectra yielded high resolution in the (15)N-dimension even for larger RNAs since the increase in line width with molecular weight is more pronounced in the (1)H- than in the (15)N-dimension. Further, we could experimentally validate the difference in relaxation behavior of imino groups in AU and GC base pairs. Additionally, we showed that (15)N-detected experiments theoretically should benefit from sensitivity and resolution advantages at higher static fields but that the latter is obscured by exchange dynamics within the RNAs