VASIMR: hope or hype for Mars exploration?

“A human mission to Mars has to overcome any number of challenges, technological and otherwise, but one of the biggest is the long travel times to go to Mars and back. NASA’s notional concept for a human Mars mission, the Design Reference Architecture, seeks to minimize that travel time with a “fast” trajectory that gets a crew from Earth to Mars in six months, with an equal length for a return trip. That’s within the experience base NASA and other agencies have accumulated on the International Space Station and Mir, but in a different radiation environment than an interplanetary mission. Moreover, an ISS crew has the ability to return to Earth within hours in the event of an emergency, an option not available for a Mars-bound crew.” Read more

Electron Beam Free Form Fabrication

“Electron beam freeform fabrication (EBF³) is a cross-cutting technology for producing structural metal parts. Developed by researchers at NASA’s Langley Research Center as a replacement for forgings, this manufacturing process offers significant reductions in cost and lead time. The promise of this technology extends far beyond its applicability to low-cost manufacturing and aircraft structural designs. EBF³ could provide a way for astronauts to fabricate structural spare parts and new tools aboard the International Space Station or on the surface of the moon or Mars. EBF³ uses a focused electron beam in a vacuum environment to create a molten pool on a metallic substrate. This layer-additive process enables fabrication of parts directly from CAD drawings. Metal can be placed only where it is needed and the material chemistry and properties can be tailored throughout a single-piece structure, leading to new design methods for integrated sensors, tailored structures, and complex, curvilinear stiffeners. The parts can be designed to support loads and perform other functions such as aeroelastic tailoring or acoustic dampening.” Source: Nasa