The Venus Express mission
The Venus Express mission has been selected by ESA across several proposals for reuse of buses and instrumentation already made for the missions Mars Express and Rosetta. The Launching Date of the mission was 9 novembre 2005 and the end of the mission is established for the end of 2016. The mission was subject to inspection in the course of 2014.
After a journey of about 150 days, reached Venus on 11 April 2006, and after a series of maneuvers (led by ESA control center in Darmstadt, Germany) to reduce the speed, has entered its final orbit on 7 May.
The height of the orbit ranges between 66,000 and 250 km from the planet’s surface, and the probe takes 24 hours to complete one orbit. Given the excellent results obtained and the potential and the perfect functionality of the spacecraft on 23 February 2007, the SPC has unanimously approved the extension of the mission until May 2009, subsequently extended until the end of 2016.
The scientific theme from which came the Venus Express mission is to seek an answer to why Venus, although size, composition, and distance from the sun comparable to the Earth has had an entirely different evolution that led him to have atmosphere and conditions soil totally different, dominated by a strong greenhouse effect such as to reach temperatures of 750 ° K. therefore the exploration of Venus can give important information about the evolutionary processes of the solar system in general and thus also of the Earth.
The Venus Express mission is investigating in detail and overall atmosphere of Venus from the point of view of its composition, its structure and meteorology in general (the study of clouds, winds, temperature etc .) and changes due to interaction with the surface, everything in order to understand the origin of the greenhouse effect. In particular we are trying to better understand the role of carbon dioxide and water in planetary evolution and in particular in the greenhouse effect. Furthermore, the discovery of atmospheric windows in the near infrared, around one micron, allow to study the atmosphere at different altitudes up to the soil, which is impossible in the visible rooms, given the enormous thickness and density of atmospheric gases (for most carbon dioxide) that reach to the ground pressures of the order of 200 atm.
Italy has contributed to the mission with the PI-ship of two instruments: VIRTIS (Visible and Infrared Thermal Imaging Spectrometer, PI Giuseppe Piccioni ASF-INAF in Rome) an imaging spectrometer in the visible / near-infrared, twin of the one in flight on the Rosetta mission, which provides data on the atmosphere, the surface and their interactions; PFS (Planetary Fourier Spectrometer, Vittorio Formisano IFSI-INAF in Rome) to scan vertical atmosphere, twin instrument flying on MarsExpress. Also there was a significant participation in the implementation of the instrument ASPERA-4 (Analyzer of Space Plasmas and Energetic Atoms) for the study of the interactions between the solar wind and the Venusian atmosphere, twin of the one in flight on MarsExpress.