The K-1 rocket being built by Kistler Aerospace is based on rockets that the former Soviet Union hoped would send its cosmonauts to the Moon. In the late 1960's and 70's the USSR built the ill-fated N1 superbooster designed to rival the US Saturn 5 that launched the Apollo moonlandings.
Despite having some powerful rocket engines the N1 never worked properly and blew up several times. The project was cancelled in 1974.
However the Kistler Aerospace corporation purchased 34 ex-N1 rocket engines last year and has been modifying them to be the key component in its K-1 rocket, the world's first fully reusable launcher.
The K-1 would be an unmanned reusable rocket. The Space Shuttle by comparison is manned and isn't completely reusable.
In the past few weeks crucial tests on the rocket engines and the fuel tanks have been successful.
The K-1 is a two-stage rocket. The first stage will burn-out at after two minutes of flight.
A cluster of six parachutes, the largest ever built, will bring it to Earth. Air bags will inflate prior to landing to cushion the impact. The second stage will also parachute back to Earth to be reused.
K-1 aims to put small satellites into space for half of the current cost. With so many small satellites awaiting launch for international mobile phone networks, the hope is that the K-1 will find a niche in the satellite launching market.