ESA’s Venus Express has ended its eight-year mission after far exceeding its planned life. The Institute of Space Science participated in the mission with a project under the ESA PECS – Programme for European Cooperating States, after Romania became an European Cooperating State in 2007, status ratified by Law no. 1/2007. ISS researchers focused on the kinetic investigation of the Earth’s and Venerian plasma layers.
Since its arrival at Venus in 2006, Venus Express had been on an elliptical 24‑hour orbit, traveling 66 000 km above the south pole at its furthest point and to within 200 km over the north pole on its closest approach, conducting a detailed study of the planet and its atmosphere.
However, after eight years in orbit and with propellant for its propulsion system running low, Venus Express was tasked in mid-2014 with a daring aerobraking campaign, during which it dipped progressively lower into the atmosphere on its closest approach to the planet. But during this campaign, Venus Express yield an orbital period of just over 22 hours.
Under the assumption that there was some propellant still remaining, a decision was taken to correct this natural decay with a new series of raising manoeuvres during 23–30 November, in an attempt to prolong the mission into 2015.
However, full contact with Venus Express was lost on 28 November. Since then the telemetry and telecommand links had been partially re-established, but they were very unstable and only limited information could be retrieved.
“It seems likely, therefore, that Venus Express exhausted its remaining propellant about half way through the planned manoeuvres last month”, said Patrick Martin, ESA’s Venus Express mission manager.
Details here.
A summary of the most important discoveries made by the Venus Express mission during its eight years of activities is available here.