Mantle (geology) Mantle (geology) The mantle is a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices, and are generally the largest and most massive layer of the planetary body. Mantles are characteristic of planetary bodies that have undergone differentiation by density. All terrestrial planets (including Earth), a number of asteroids, and some planetary moons have mantles. The Earth's mantle is a layer of silicate rock between the crust and the outer core. Its mass of 4.01 × 10 kg is 67% the mass of the Earth. It has
What Shall We Do Now? sped up, to raise its key to E minor, with re-recorded vocals and guitar. The members of Pink Floyd have contributed to the confusion regarding the identity of this track, misidentifying "What Shall We Do Now?" as "Empty Spaces" on multiple occasions, such as in the track listing for the film version of "The Wall", and on Waters' "The Wall Live in Berlin". On other occasions (such as the officially released live version), the first and second parts of the track are divided and identified as "Empty Spaces" and "What Shall We Do Now?" respectively, even though they are in