After the condensed material accretes to planetesimals of sufficient size melting and differentiation take place. Earth accretes or ejects near-Earth asteroids on million-year time scales, thereby clearing its orbit. If more mass accretes onto a neutron star, eventually this mass limit will be reached. Some of the matter lost by the M giant accretes onto the white dwarf. In the second, the planet accretes from both water-rich and iron metal-rich material. As ice accretes on the surface, the torque required to rotate the scraper increases. As ice accretes on the tube, the signal is blocked and sets ice alert.