kgeiger (1339271) writes "John J. Chapman, a physicist and electronics engineer at NASA’s Langley Research Center, envisions a laser-pumped fusion drive. Chapman estimates the drive can produce thrust 40 times more efficiently than existing ion engines such as those on the Dawn mission now exploring the asteroid belt." Link to Original Source
You see but you do not observe.
Sir Arthur Conan Doyle, in "The Memoirs of Sherlock Holmes"