The drill head of the DISC Drill with a core inside the drill barrel. The rotating drill head contains four razor sharp cutters that shave out an annulus of ice, which the drill then slides down into. As the drill slides down into the annulus it slides over the core, which is 122 mm (4.8 inches) in diameter and 2.7 meters long. When a cable pulls up the drill, four cams grab the core and break it free. After the drill is pulled back to the surface it is lowered from a vertical to horizontal orientation so that the ice core can be removed from the drill barrel. Credit: Jay Johnson