Bremen, 01 July 2021 - OHB System AG, a subsidiary of the technology and space group OHB SE, will be defining the structure and thermal system for the European Venus orbiter EnVision under a subcontract from Thales Alenia Space. The mission was selected for implementation by the European Space Agency (ESA) on 10 June and is expected to provide revolutionary insights into the geological evolution of Venus.
Venus: Earth's sister planet
Venus is Earth's closest neighbouring planet and is similar to it in size, mass and chemical composition. Nevertheless, the conditions on the two planets could not be more different. Unlike the other terrestrial planets in our solar system, Venus has a permanently opaque and extremely dense atmosphere, which consists of a good 96 percent carbon dioxide and weighs down on the planet at the mean ground level with a pressure of 92 bar. The clouds of Venus are mainly composed of sulphuric acid droplets and although they reflect a large part of the solar radiation, the average surface temperature on the planet is 460 °C. This is due to the strong greenhouse effect, which is primarily caused by the high amounts of carbon dioxide in the atmosphere.
Why have Venus and Earth evolved so differently?
Why Earth and Venus have developed so differently since the formation of the solar system is one of the core questions to be answered by EnVision. The mission is the fifth medium-class mission selected for implementation in ESA's Cosmic Vision programme. Another medium-class mission within the programme is the PLATO mission led by OHB as prime contractor. In order to be able to collect comprehensive data on the surface properties, internal structure and atmospheric composition of Venus, EnVision is to be equipped with a suite of different instruments. These include a synthetic aperture radar (SAR) contributed by NASA as well as several spectrometers.
EnVision succeeds ESA's highly successful Venus Express mission, which explored Venus' atmosphere from 2006 to 2014 and provided ground-breaking insights into volcanic hotspots that may be present on the surface of Venus. Together with NASA's recently announced new Venus missions DAVINCI+ and VERITAS, EnVision will provide the most comprehensive data yet on Earth's sister planet.
"We know very little about Venus – even though it is the closest neighbouring planet to our Earth," emphasises Marco Fuchs, CEO of OHB SE. "This is one of the reasons why we have launched the #DestinationVenus series in 2019 to draw attention to the significance of a new European Venus mission. I am all the more pleased that EnVision has now been selected for implementation."
"Venus is a highly exciting planet," adds Jan Knippschild, Project Manager for EnVision at OHB. "We are pleased to be able to contribute our expertise to defining the mission."
EnVision is expected to be launched on an Ariane 6 launch vehicle. The first launch window for the mission opens in 2031, with further possibilities in 2032 and 2033.