“Darts is a first step whose success is incredible”, welcomes Wednesday 12 October at franceinfo Patrick Michel, Research Director at CNRS, at the Côte d’Azur Observatory, Scientific Director of the Hera mission of the European Space Agency. A little more than two weeks after NASA’s Dart mission that made it possible – at the end of September – to deflect the asteroid Dimorphos from its orbit.
>>> VIDEO – Mission Dart: a NASA spacecraft hits an asteroid to deflect its trajectory, a historic first
The researcher reviews the first lessons that can be learned and the next steps. “We have Hera on track to complete […] to give us the result of the impact […] Without this information, it is difficult to interpret why we have deviated so much”he explains before adding: “We have already skipped steps [mais] We are still in a learning phase.”
franceinfo: We knew the mission was successful, but what have we learned with the data collected over the past two weeks?
patrick michael : It is absolutely extraordinary. Thanks to this Dart mission, we demonstrated that we were able to hit an object 11 million kilometers from us, initially knowing only the size of the object and detecting an hour before the impact – in a way autonomous for the probe – the form when successfully entered. The other thing is that we have actually succeeded in deflecting the path more than we expected thanks to an internationally coordinated observing campaign from Earth: we have about thirty telescopes covering almost all the continents, which have organized themselves to be able take this measurement and I find it extraordinary.
How did Europe and France participate in this mission? ?
France participated because several of us are members of the Dart team. You should know that this Dart and Hera project was first born in Europe in the 2000s, then from a conversation between me and an American colleague who proposed ESA (European Space Agency) and NASA to do a diversion mission together. France was therefore involved from the start in this mission and also in the Earth observation component, as we have a telescope in Antarctica called Astep – which belongs to the Observatory of the Côte d’Azur – and other instruments that helped measure this change in Dimorphos’ orbit.
What perspective does it open up for us?
We have started this road map well, which should lead us to have a valid plan that we can offer to future generations to address this risk the day it becomes a reality, so that they do not have to improvise. that day because there is several stages left. through: first you must be able to predict the threat, prevent it and you must be able to coordinate internationally, both politically and legally. In the UN we have working groups that try to get a coordinated organization at this level. Dart is therefore a first step, the success of which is incredible, it is fantastic, and we have Hera, which comes to complete. Without this mission, which will come in four years to give us the results of the impact: what was the size of the crater? How much deviation did we produce? What is the internal structure of this object? etc. Without this information it is difficult to interpret why we have deviated so much.
Will there be more missions like this to refine?
There we know that this technique seems to work well and we will be able to quantify all that with Hera, but we are still in a learning phase. They were thought to be boring little rocks in space, and indeed asteroid missions have revealed to us tiny worlds of extraordinary geological complexity. The goal is at some point to stop being surprised and to know what we are dealing with. So that was a first step, and we have other missions that will see objects crossing Earth’s orbit without deviating for the time being to learn even more about their diversity. But it is a first step and from the first test we managed to do something beyond our expectations. So we have already skipped steps. Today, at least, none of the objects we know of threaten us for at least a century. Knowing also that all this allows to develop technologies and to learn scientifically about the remains of the bricks that formed our planets that make up these asteroids.