Vastitas Borealis, the area that Phoenix has landed in, gets covered in a metre-deep layer of frozen carbon dioxide.

ECONOMIST: Space exploration

Vastitas Borealis, the area that Phoenix has landed in, will be covered in a metre-deep layer of frozen carbon dioxide.

ECONOMIST: Exploring Mars

This is made possible by the fact that Blu-ray uses a 405nm laser to read its 0.1mm deep info layer, while HD DVD uses the same blue laser wavelength at the depth of 0.6mm.

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