The cometary material that the Deep Impact collision kicked up was so copious and reflective that cameras and instruments could not see the crater itself. But the scientific return of the impact was enormous. For the first time, astronomers were able to study the unaltered ice and dust that existed in the solar system more than four billion years ago. The result also showed how soft—and powdery!—comets can be; this will be important if humans someday need to move a comet hurtling toward Earth, because using the wrong technology on the wrong material would not do the job.