The European Space Agency warns that space debris must be removed to prevent potentially catastrophic collisions with operational spacecrafts and satellites. The head of the space debris office, Heiner Klinkrad, warns that that as more rubbish is left from human exploration of outer space, the possibility of collisions increase. "A ten centimetre object would be capable of totally shattering a spacecraft," he warns. One plan is to harpoon the waste and remove it