Jet-powered submarine is

German scientists have created a steerable jet-powered submarine under 1mm across. Compared with 16m coin, is the 0.8 x 0.8 x 0.14mm submarine The sub has been built by the Chemnitz University of Technology and consists of two tubular engines, one on either side of a flat body. It swims in its own mono-propellant fuel – ...

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