Venus Express – VEX for short – launched in 2005 was the first and up to now only ESA mission to explore the planet. Venus, our inner neighboring planet is relatively little explored as compared with Mars. This is due to the forbidding temperatures on the surface – about 450°C – and its corrosive, optically thick atmosphere. The latter prohibits exploration of the surface with standard cameras and motivates the use of radar and infrared mapping. Venus is close to the Earth in terms of mass and radius but its atmosphere likely underwent runaway greenhouse heating that removed any water that may have been on the surface in its early days. Venus orbits closer to the Sun which explains part of the heating and its atmosphere – much more massive than Earth’s – is dominated by carbon dioxide, an effective greenhouse gas. Planetary scientists also wonder about the lack of a magnetic field and its tectonic evolution and whether it ever had anything like Earth’s plate tectonics. VEX has been orbiting and exploring the planet for a decade before it was commanded to dive into the atmosphere where it burned taking measurements until the end in early 2015.
VEX profited substantially from hardware developments for Mars Express and Rosetta, also for its suite of instruments. It was equipped with a plasma and energetic particles analyzer, a magnetometer, spectrometers for the ultraviolet, visible and infrared parts of the electromagnetic spectrum, a radio science package and a monitoring camera. Venus Express for the first time observed the south polar region on the night side of the planet and discovered atmosphere vortices that circle the pole. In particular its mapping infrared spectrometer detected anomalies in the thermal surface emission which might be proof of recent volcanic activity. An ozone layer was discovered by the ultra-violet spectrometer. Venus Express has motivated scientists to propose follow-up missions, three of which are under consideration by ESA and NASA.
Dr. Ann Carine Vandaele is the head of the Planetary Aeronomy Group at the Royal Belgian Institute for Space Aeronomy and the Principal Investigator of the SOIR infrared spectrometer, a part of the SPICAV package of spectrometers on the mission. Ann C. Vandaele is a civil engineer and a physicist by training and has been involved in Earth observation as well as the spectroscopic study of Mars and Venus. She is a highly cited expert of planetary spectroscopy.
This Seminar was recorded on August 27, 2020