During the Herschel cryostat evacuation some of us took the chance to see a leatherback turtle nesting. Leatherback turtles' front flippers can grow up to 2.7 metres. Adults average at around one to two metres long and weigh to 700 kilogrammes. Leatherbacks are also the deepest reptile divers - some have been discovered at depths deeper than 1,200 metres.
