Predicting the location of the termination shock was hard, the researchers say, because the precise conditions in interstellar space are unknown.

BBC: Voyager impression (Nasa)

The films, showing man in space, on the Moon, on Mars, and the "unknown", fascinated the boy Rutan.

BBC: The Moon

And just as some early explorers made the ultimate sacrifice while searching for unknown lands, space pioneers may also pay a steep price for bravely going where no human has gone before.

CNN: Mars on the brain? Red Planet pioneers to face cosmic mind trip

My work is trying to map that in-between space between known and unknown, the constant hovering between two states.

ECONOMIST: Contemporary art

Negroponte says an unknown wiki contributor suggested that the caps lock key be eliminated to save space.

FORBES: Can a network build a potentially huge new product?

The Zumwalt has the power, cooling, space and weight margin designed to meet the full spectrum of future threats, both known and unknown.

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