Europe wants to clean up the space behind it

After providing valuable data on wind patterns around the Earth for five years, the Aeolus satellite is about to finish its mission by disappearing. At least that’s the stated goal of the European Space Agency, which funded it. “Man, in the same way he polluted the land and the ocean, has polluted space“ Luisa Innocente, Head of the Clean Space Office at the European Space Agency, acknowledged. “Not all space, but the orbits are protected, the so-called low orbits from 0 to 2000 km and the geostationary orbit [36000 km d’altitude, NDLR]. We scientists have been alerted for some time about this“.

In the wake of CNES, the French agency that established a code of conduct in 2008, The European Space Agency is studying ways to reduce the debris. A satellite is considered to have completed its mission as such if it is not absorbed. It comes over 30,000 objects larger than 10 cm that roam in space and make space traffic more and more dangerous, as the risk of collision increases.

AEOLUS fall, Fadhel shutdown test

Now, more and more space players are trying to respect the rules and show that they are virtuous. Easier said than done It’s hard to go and clean up the space trash. Many methods are being explored, and controlled return is the least sophisticated of the methods, one might be tempted to say. In this context, AEOLUS is scheduled for this week.

The 1366-kilogram satellite, operating from an altitude of 400 km, naturally and slowly descends towards us, attracted by the Earth’s gravity. The engineers will perform three pushes with the actuators in order to reach different levels and perform the final click, the accuracy of which is essential. The ultimate goal is to reduce the area of ​​impact as much as possible : charted in the Atlantic Ocean, dated “A very long stretch of ocean where there is nothing or almost nothing, no islands, little marine traffic, and where the risks are very low.”According to Benjamin Bastida Virgili, an engineer who specializes in space debris at the European Space Agency’s center in Darmstadt, Germany. This should only last a few hours, and only 20% of the satellite will disintegrate under the thermal effect of atmospheric friction.

From Monday, the first push should lift Aeolus from 280-250km. After a few days of downtime, Isabelle Rougeau, specialist in space maneuvers at the European Space Agency, announces a second series of orbit correction to reach an altitude of 120 km on Friday, another flick day that will mark the final stage of the journey: crossing the layers of the atmosphere. The satellite will begin to disintegrate from a distance of 80 km.

Predict where a rock will fall after 15 ricochets.

Managed from the Technical Center in Darmstadt, these operations have never been tried by the European Agency. Include part of the unknown Because of the high solar activity at that time. Through its influence on the satellite’s electronics, it can adjust the progress of maneuvers. Moreover, Dominique Gillieron, Director of Optical Instruments at Airbus Defense and Space explains, “At 7 km/sec the satellite is going really fast and if you make a mistake for one minute in expecting to enter the atmosphere you’ve already moved 500 kmIt’s the details.

Thus, the uncertainty about the point of impact is still very large, particularly along the north-south axis. He compares the situation to a person bouncing off a rock on the edge of a lake :”Our problem is that we have to predict exactly where the pebble will fall after 15 ricochetes. It’s the same level of difficulty we’d ask our experts today because the satellite will bounce a bit as it rubs against the atmosphere. The way it arrives, whether it rotates or not, will mean it will stay maybe 20 seconds longer in the atmosphere rather than straight back up. Good luck making an accurate prediction! “Concludes.

If all the components of a Hollywood disaster scenario are met on paper, There is little chance that this deorbit could end badly. Even if they abandon the planned plan, Aeolus can naturally return to Earth. It will be slower, with a “splash” or “bang” around mid-August.

Towards a “space trash cargo ship”?

If rules are enacted to control these re-entries as much as possible when they are not assisted, then ESA is considering sensitive or complex situations. Those generated from satellites that, at the time of their construction, did not take into account a controlled orbital de-orbiter in order to free up space. Premature failure of engines and interruption of communications with the ground … We have to anticipate the future. “The European Space Agency is preparing standards to achieve zero debrisinsists Luisa Innocenti.Today, 25 years after the end of its life, the satellite must be removed from its position. It is a matter of reducing this period to five years. “

Being able to catch a satellite going negative is much more difficult. Hence the implications for new technologies. Sending a satellite to deorbit another isn’t much use, but inventing a “space junk cargo ship” isn’t easy either. It would be necessary to consider adding a grab handle, even sensors to know exactly where they are. Depending on the orbits, the satellite can stay longer or shorter in space. However, some jobs are highly desirable and again, require you to remain available. For this, beds are needed more than before, which have not yet been invented.