Surprising results from recent asteroid missions have highlighted the importance of testing planetary defence strategies in space, according to scientists participating in the joint ESA/NASA Asteroid Impact and Deflection Assessment (AIDA) collaboration. The unexpectedly large crater on asteroid Ryugu created by the JAXA Hayabysa2 impactor, together with the sand-like behaviour of material on its surface, further motivate the need to determine the effectiveness of proposed deflection techniques for an asteroid on a potential collision course with Earth. Implications are being discussed this week at the EPS-DPS Joint Meeting 2019 in Geneva.
![](https://scx1.b-cdn.net/csz/news/tmb/2019/aidacollabor.jpg)
Source:
https://phys.org/news/2019-09-aida-collaboration-highlights-case-planetary.html