Star Trek's faster-than-light warp drive is an idea that even serious scientists don't want to let go of.
A ring-shaped warp drive device could transport a football-shape starship (center) to effective speeds faster than light. The concept was first proposed by Mexican physicist Miguel Alcubierre.
NASA's Project Orion, which was initiated in 1958, proposed propelling a spacecraft by detonating a series of atomic bombs behind the vehicle, a concept known as nuclear pulse propulsion.
Daedalus Ignition - In the 1970s, Project Daedalus proposed powering a spacecraft using a nuclear fusion rocket.
A concept image of a spacecraft powered by a fusion-driven rocket. In this image, the crew would be in the forward-most chamber. Solar panels on the sides would collect energy to initiate the process that creates fusion.
Nuclear Fusion Rocket Test Chamber - The fusion driven rocket test chamber at the UW Plasma Dynamics Lab in Redmond. The green vacuum chamber is surrounded by two large, high-strength aluminum magnets. These magnets are powered by energy-storage capacitors through the many cables connected to them. Image added April 10, 2013.
Antimatter Engine-An artist's concept of an antimatter engine, which would harness the immense energy released when antimatter and matter meet.
Solar Sail in Space - The Sunjammer project, slated to launch in 2014, will demonstrate "propellantless propulsion" offered by solar sails.
Sunjammer Solar Sail Prototype-An early prototype of L’Garde solar sail is evaluated in a vacuum chamber at the NASA Glenn Research Center’s Plum Brook Facility in Sandusky, Ohio. This test article is a quarter the size of the sail the company plans to fly in 2016.
VARIES – Vacuum to Antimatter Rocket Interstellar Explorer System, is a concept from Richard Obousy that would use enormous solar arrays to generate power for extremely powerful lasers, which, when fired at empty space, would create particles of antimatter which could be stored and used as fuel. The process would be used at the vehicle's destination to create fuel for the return journey.
A potential spacecraft called Icarus Pathfinder would be powered by electromagnetic VASIMR (Variable Specific Impulse Magnetoplasma Rocket) engines, taking it out to 1,000 times the distance from Earth to the sun
