Particles (known as meteoroids) that come from interplanetary space, on the other hand, are natural.

ECONOMIST: Orbital debris

Because there are more DA14s filling interplanetary space than YU55s, a 50-foot asteroid can be found in a smaller volume of space, on average, and thus closer to Earth, than a 150-foot one.

CNN: A meteor and asteroid: 1 in 100 million odds

Then, there is the LIFE biomodule, which we piggybacked in the Grunt mission simply to get it into interplanetary space for as long as possible, 34 months in the case of this mission.

MSN: Salvaging Science from Stricken Mars Moon Probe: A Scientist's View - Technology & science - Space - Space.com | NBC News

By interplanetary space, we are talking about an environment in which space radiation is much more intense than it is in LEO, because above Earth orbit is the geomagnetosphere, the Van Allen belts, which trap charged particle radiation coming from deep space.

MSN: Salvaging Science from Stricken Mars Moon Probe: A Scientist's View - Technology & science - Space - Space.com | NBC News

He climbed out of the car creakily, as if out of a space capsule after an interplanetary voyage.

NEWYORKER: We Are Alive

These habitats, which are folded up for launch and then inflated in space, were designed as interplanetary vehicles for a trip to Mars, but they are also likely to be useful general-purpose accommodation.

ECONOMIST: The Americans may still go to the moon before the Chinese

Some of the technology has come from ideas suggested by the Interplanetary Network, which is looking at ways of providing net connectivity in space.

BBC: Hi-tech answer to reindeer tracking