Not exact matches
In addition, if the melted nuclear fuel proves bad
enough — like Chernobyl's lethal mass of molten core known as the «elephant's foot» — it will have to be entombed for a number of years rather than removed, because of radiation risk from what is essentially a cooled shell of ceramic armor surrounding a highly
radioactive core that remains hot and is still undergoing
radioactive decay.
Natural circulation in the reactor alone is
enough to remove all the heat generated by the
radioactive decay of the elements in the reactor fuel.
In a series of papers published online today in Science, researchers report that according to Dawn observations, Vesta did indeed agglomerate
enough rocky debris as it grew to heat itself by the
decay of the rock's
radioactive elements.
Vesta appears to have been large
enough and hot
enough to melt internally from
decaying radioactive elements as well as impacts so that lighter elements floated upwards from denser material to form layers towards its surface.