* Astronomy

'Gigantic chasm under Antarctic ice'

A vast, previously unrecognised canyon system could be hidden under the Antarctic ice sheet.
Hints of its presence are seen in the shape of the white continent's surface, in a largely unexplored region called Princess Elizabeth Land.
If confirmed by a proper geophysical survey - now under way - the winding canyon network would be over 1,000km long and in places as much as 1km deep.
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