A huge iceberg broke off Antarctica. What scientists found under it stunned them / The megaberg: Bigger than London and five times the weight of Mt Everest - the impact of the world's biggest iceberg / We used 1,000 historical photos to reconstruct Antarctic glaciers before a dramatic collapse / Researchers use 1,000 historical photos to reconstruct Antarctic glaciers before a dramatic collapse / Scientists probe the secrets of mega icebergs / Incredible picture of polar bear snoozing atop an iceberg is a winner / New animation shows track of giant A23a iceberg / ISS astronaut snaps amazing photos of icebergs from space / 'Incredibly lucky': Antarctic scientists examine world's largest iceberg, three times the size of NYC / Video shows ship's "lucky" encounter with world's largest iceberg