A launch loop or Lofstrom loop is a proposed system for launching objects into space orbit using a moving cable-like system situated inside a sheath attached to the earth at two ends and suspended above the atmosphere in the middle. The design concept was published by Keith Lofstrom and describes an active structure maglev cable transport system that would be around 2,000?km (1,240?mi) long and maintained at an altitude of up to 80?km (50?mi).