NASA’s DART Collision Reshapes Asteroid, Dimorphos’ Rubble-Pile Structure Discovered

NASA’s recent Double Asteroid Redirection Test (DART) mission successfully collided a spacecraft into the asteroid Dimorphos to adjust its orbit. Now, new research analysing the collision’s aftermath indicates Dimorphos likely underwent significant physical changes. Computer simulations of the event suggest the asteroid has a “rubble pile” composition that deformed extensively upon impact. These revelations enhance our comprehension of asteroids’ structures and dynamics while proving the viability of kinetic impactor techniques for future planetary defence strategies.

Dimorphos’ Rubble-Like Formation

The DART mission analysis divulges that Dimorphos potentially possesses a loose, rubble-pile configuration – formed from material spewed out by its larger companion asteroid Didymos during its spin cycle. Models recreating the collision aftermath demonstrate Dimorphos’ minimal internal cohesion, sparse boulders, and considerable post-impact deformation and mass redistribution. Over 8% of the asteroid’s original mass shifted positions, with interior constituents emerging onto its surface. This points to a global deformation far surpassing the creation of a simple surface crater. The insights bolster our knowledge of the composition and responsiveness of small binary asteroids when subject to high-velocity collisions.

Implications for Planetary Defense

The revelation of Dimorphos’ malleable rubble-pile structure bears significance for impending planetary defence tactics involving asteroid impact redirection. Kinetic impacters rely on transferring momentum from spacecraft to asteroids to successfully alter their paths. The DART mission affirmed this method’s effectiveness on loosely-held rubble piles like Dimorphos, with observations validating the considerable orbital changes achieved. The models provide vital data to enhance asteroid redirection approaches and the design of future kinetic impactor spacecraft. The 2027 Hera probe will further analyse Dimorphos post-collision to supplement these discoveries and assist scientists in refining asteroid deflection strategies.

DART’s successful collision with Dimorphos has expanded our asteroid science beyond proving the feasibility of trajectory alteration through kinetic impactors. The observed physical changes in Dimorphos reveal vital clues into asteroid compositions and structures while showcasing their susceptibility to artificial deformation. As we advance our planetary defence capabilities, missions like DART provide vital empirical insights to continuously upgrade our asteroid mitigation plans.