A European-Russian attempt to reach Mars was hit by another parachute failure, during a drop test in Sweden. cannot afford another failure.
This means that the next test is critical if the mission is to prevent a delay in its target launch by July 2020.
The plan is to send a platform over Russia and a European rover down on the Martian surface.
European Space Agency (Esa) Rosalind Franklin rover will collect soil samples with drill and analyze them for the availability of organic material. This may give clues to the existence of past or present life on Mars. a carrier module on their six-minute journey down to the surface.
During a high-altitude test on 5 August in Kiruna, Sweden, a mass test designed to represent the combined lander and rover descended from a stratospheric helium balloon to a height of 29km.
Engineers tested the largest of the two main parachutes, measuring 35m wide, designed to slow the vehicle to a speed necessary to reach Mars safely. The European Space Agency says it's the largest ever to fly a Mars mission.
However, the test article fell to the ground at high speed. Preliminary testing shows that the initial parachute deployment steps are being carried out correctly. However, specialists saw radial tears in the canopy of the parachute before its inflation.
As a result, the test module falls under the drag of the pilot chute alone.
The same tear problem was detected in a previous test at the Esrange site of the Swedish Space Corporation, on 28 May. The balloon drop test was designed to test the deployment of two main parachutes and the pilot chutes designed to retrieve them from the bags in the descending module.
Changes were made to the design of the parachutes and bags following that test, but they apparently did not solve the problem.
"The test took place eight days ago, as you can imagine, the test is still running. We need to have a good understanding of the root cause as we have an additional opportunity to resolve the issue. this, "said Nico Dettmann, head of the human and robotic exploration development project team at Esa.
"We have two remaining test windows. One is in November, one is in February next year. If these tests are okay we will be on a July flight. However, if the one of them will fail, we will not accept the risk. The success of our mission is the first priority. "
He told BBC News:" But once we are confident we will find a fix and implement this in time. "
If Exomars misses its launch window in 2020, the next opportunity to fly the mission will come in 2022, when Mars and Earth take another close approach.
But Nico Dettmann emphasized that there was much more to this decision than favorable alignment with the planet. "This does not happen automatically. There are a number of programmatic questions that will be clarified to key stakeholders.
" The key stakeholders are not only our partners in Russia, but also our member states. If we had to postpone it would obviously cost more money. This is something that is not yet under discussion because we are still hopeful that we can make the launch by 2020. "
A low test conducted in March 2018, in which a large mass fell from a helicopter , was successful.
The Rosalind Franklin rover is in the final stages of completion at the Airbus & # 39; s facility in Stevenage, UK.The engineers are running the final assembly tasks and are expected to produce six wheeled vehicles out of doors before the end of August.
The Roscosmos & # 39; Kazachok landing platform (the name translates as "little Cossack"), will carry a suite of instruments developed in countries including Belgium, Spain and Finland – in addition to experiments developed by Russia. It is also close to completion.
As it stands today, the mission should be launched on a Proton rocket of Russia from the Baikonur Cosmodrome in Kazakhstan in July next year.
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