The habitability and detection of Earth-like planets orbiting cool white dwarfs. ... As a white dwarf cools from 6000 K to 4000 K, a planet orbiting at 0.01 AU would remain in the Continuous Habitable Zone (CHZ) for 8 Gyr. ... Polarisation due to a terrestrial planet in the CHZ of a cool white dwarf is 10 2 (104 ) times larger than it would be in the habitable zone of a typical M-dwarf (Sun-like star). ... 11 ґ Table 1: Polarisation obtained for a planet in the CHZ of a T eff =5000 K white dwarf. ...