Earth about under the oceans to for the continents. The crust and the cold, rigid, top of the upper mantle are collectively known as the lithosphere, and it is of the lithosphere that the tectonic plates are composed. Beneath the lithosphere is the asthenosphere, a relatively low-viscosity layer on which the lithosphere rides. Important changes in crystal structure within the mantle occur at below the surface, spanning a transition zone that separates the upper and lower mantle. Beneath the mantle, an extremely low viscosity liquid outer core lies above a solid inner core. The Earth's inner core might rotate at a
What on Earth June 1975 and from May to August 1977. What on Earth What on Earth is a Canadian television panel game show and discussion program which aired on CBC Television from 1971 to 1975. It was based on the 1959 CBC game show "Who Knows?" The series featured items from the Royal Ontario Museum, the Ontario Science Centre and other facilities. These were brought before a panel who attempted to identify the objects. After the object's identity was guessed or revealed, it was the subject of further conversation by participants. This half-hour series was broadcast as follows (times in Eastern): Episodes