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There is some belief that the magnitude of this energy may make interstellar travel impossible.

It has been reported that at the 2008 Joint Propulsion Conference, where future space propulsion challenges were discussed and debated, a conclusion was reached that it was improbable that humans would ever explore beyond the Solar System.

Brice N. Cassenti, an associate professor with the Department of Engineering and Science at Rensselaer Polytechnic Institute, stated “ At least 100 times the total energy output of the entire world would be required for the voyage ( to Alpha Centauri )”.