A message from P. Mitschdoerfer, ExoMars Mission Manager:
Five years ago, on 14 March 2016, our ExoMars 2016 Mission lifted-off from Baikonur on a Proton-M/Breeze-M launcher. It was a launch that could not have been better – Proton put the Spacecraft Composite (SCC) on the perfectly-right trajectory towards Mars, no Launcher Correction Manoeuvre was necessary. TGO was the heaviest Mars orbiter ever designed and launched to deliver a lander to Mars.
Our ExoMars SCC made it to Mars, Schiaparelli was successfully released from TGO and although the landing part of the EDL was not successful, Schiaparelli provided all its flight data to TGO during that critical phase such that we could perform a detailed assessment and define lessons learned and implement them for the Rover and Surface Platform (RSP) mission. TGO then fired its main engine to enter into Mars orbit. On 15 March 2017 Aerobraking started and it ended after 952 passes through the atmosphere with the Aerobraking walkout manoeuvre which was performed on 20th February 2018 at an apocentre altitude of ~1047 km. The pericentre was raised from 109 km (inside the atmosphere) to 200 km (well above). The orbital period reached with Aerobraking was 2 hours 6 minutes, and a few small propulsive manoeuvres followed to reach the final science and relay orbit with a pericentre at 360 km and an apocentre at 413 km. TGO was the first ESA spacecraft that was ever designed and used for aerobraking to reach its science orbit.
Since April 2018, TGO delivers excellent science – for instance, as of today:
• NOMAD and ACS instruments have established upper limits of methane in the atmosphere at a level more than ten times less than the previously claimed numbers of detection - this basically indicates a complete lack of methane, a phenomenal mystery that still needs to be solved.
• Hydrogen Chloride (HCI) was detected in the atmosphere for the first time.
• The first detection of Ozone in the InfraRed.
• Detection of a high variability of deuterium-to-hydrogen ratio (D/H) in water vapour over the seasons, confirming that large amounts of water have been lost over time.
• FREND has identified numerous water-rich ‘oases’ at shallow depths (0-100 cm) at near equatorial latitudes, with great implications for future explorations.
• the 20.000th image of Mars was taken by CaSSIS on 13th Dec 2020, and by now even more, including 1500 stereo pairs and detailed images of the landing sites for RSP in Oxia Planum and for Perseverance in Jezero Crater.
TGO performed its first data relay session with Curiosity on 23rd April 2018 and since then TGO serves as the first European Orbiter to routinely provide data relay for the NASA landers on Mars: Opportunity (until it stopped communicating mid 2018), Curiosity, InSight and Perseverance. TGO returned almost 58% of the Perseverance data in the first two weeks after landing.
The total science data relay volume which TGO achieved so far is remarkable (>26000 Gbit), also thanks to TGO being the first European Orbiter to routinely use Russian Ground Station Antenna as part of the ESA-ROSCOSMOS ExoMars cooperation.
WHAT AN ACHIEVEMENT! This all would not have been possible without your outstanding contribution and team spirit – you can be more than proud of this.
TGO will soon prepare for supporting our RSP mission: in August 2021 a series of TGOmanoeuvres are planned which will phase the TGO orbit to support Rosalind Franklin rover and Kazachok surface platform 1st data relay pass after landing on 10 June 2023. The challenging ExoMars 2016 mission continues and will hopefully bring further achievements together with joy and happiness.