To transport a spacecraft to distances far beyond the solar heliosphere and around planets of other stars will require advanced space propulsion systems that go existing technological state art. The release fusion energy from interaction two low mass atomic nuclei are able overcome Coulomb barrier offers potential for ∼1011J/g specific implies robotic missions nearby ∼5–10 ly may be possible in...

Fusion energy research began in the early 1950s as scientists worked to harness the awesome power of the atom for peaceful purposes. There was early optimism for a quick solution for fusion energy as there had been for fission. However, this was soon tempered by reality as the difficulty of producing and confining fusion fuel at temperatures of 100 million ◦C in the laboratory was appreciated. ...

As discussed in the preceding article, direct-drive inertial confinement fusion targets require a cryogenically cooled spherical shell in which the DT fuel is condensed in a uniform layer on the inner wall. Optical interferometry is the predominant technique used to characterize the thickness and uniformity of the cryogenic fuel layer. In addition to inherent optical limitations such as spheric...