The team led by physicist and former astronaut Franklin Chang –tied in
first place with the most NASA shuttle missions at 7—successfully
tested the plasma engine that will eventually take man to Mars. After
years with the Vasimr rocket in blueprints, Chang and his colleagues
actually tested the first stage of the VX-200, the scale prototype of
their spacecraft. The test was conducted at the Ad Astra Rocket lab in
Houston, Texas, which is working on the project with its similar
facility at Liberia, Costa Rica.
Source: La Nacion