Surfing the Martian Atmosphere

The activity to do with Mars is moving at quite some pace with the European Space Agency completing a series of manoeuvres of it’s ExoMars Trace Gas Orbiter to slow it down and place it in orbit around Mars. This orbiter also has a NASA payload to help communications with NASA rovers and missions on the Martian surface such as the Mars InSight lander, when it gets there. ExoMars is all about astrobiology and will search for evidence of past life on Mars. The mission comes in a few parts including a satellite, lander and eventually a rover. Unfortunately the lander crashed but the satellite is doing well and is slowly getting into its optimum orbit.

ExoMars is a joint programme between the ESA and Roscosmos that comprises of two launches, one was done in 2016 and the second will be in 2020. The aim of the mission is to search for evidence of past life on Mars. The various spacecraft that are there or will be sent are designed to look for signatures in the different environments where they will operate. The first two missions were launched together on 14 March in 2016 and included the Trace Gas Orbiter and the Schiaparelli lander.

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The launch of the ExoMars first part (Credit: ESA)

The Trace Gas Orbiter is currently doing a range of complex orbital manoeuvres to get it close in near the Martian atmosphere. Since March 2017 the spacecraft has been dipping into the upper reaches of the atmosphere to slowly decrease it’s speed by a whooping big 3600 km/h. During some passes the spacecraft has got as low as 103km above the Martian surface as it sought to take advantage of the drag created by the atmosphere to slow down. On the 20 February the aerobraking manoeuvring was halted and the spacecraft was raised up to a 1500km X 200km orbit at it’s lowest point. Over the next month they will continue to modify the orbit by firing thrusters every few days to finally achieve a circular 400km orbit. The science mission is planned to begin around 21 April after some checks are done of the instruments.

The goal of the mission is to understand the trace gases in the Martian atmosphere, especially methane which may be an indicator of active biological or volcanic activity. The spacecraft will also have a camera that will look at the surface to identify any trace gas sources. The final part of the orbiter’s payload is radio communications provided by NASA to enable communications relay between the Earth, the orbiter and rovers and landers on the surface.

The Schiaparelli lander was separated from the Trace Gas Orbiter on 16 October 2016 and manoeuvred to Meridiani Planum. This spacecraft was designed to test the technology of going to the Martian surface for the future rover part of the ExoMars mission. It was supposed to descend and take measurements of the atmosphere and once on the ground to measure wind speed, direction, humidity, pressure and the temperature.

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Schiaparelli EDM (Credit: ESA)

It was also supposed to measure transparency and electrical conductivity of the atmosphere. The landing was supposed to take place on the 19 October 2016 but no communications were maintained with the lander and it was assumed it had crashed. The below picture was from the Mars Reconnaissance Orbiter is of what is believed to be the crash site of the lander (credit: NASA).

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The next part of the mission is programmed to launch in 2020 and will involve putting the ExoMars lander and rover on the surface. This is a joint build between Roscosmos and the ESA. The plan is to use a combination of parachutes and rocket thrusters to bring the spacecraft to the surface on legs. Then the rover will split away from the lander component and go off and do it’s mission, it will basically drive out off the lander down a ramp. The lander component will have it’s scientific mission of measuring the atmosphere, radiation and searching for any evidence of water. The lander will operate for about a year while the rover drives around the surface conducting it’s mission. The rover will have an astrobiology suite of scientific instruments on board which will be used to search for signatures of biological activity in the past. It will also have a drill so it can carry out some tests on the Martian soil within it’s onboard lab.

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ExoMars Rover (Credit: ESA)