New Delhi: During the celebrations for the second National Space Day at Bharat Mandapam on Saturday, an updated roadmap for ISRO was revealed. The roadmap reveals
a number of exciting space transport hardware. This includes a vertical takeoff, vertical landing (VTVL) vehicle capable of hopping across or between planetary surfaces, a space tourism rocket for short duration suborbital flights, the Hypersonic Airbreathing Vehicle with Airframe (HAVA) which is an autonomous SCRAMJet platform, reusable spaceplanes for military or scientific payloads, and even a fully reusable two stage to orbit space shuttle. One of the technologies on the roadmap though, requires so much electricity that humans have not yet developed a suitable power source, and it is called VASIMR.
VASIMR stands for Variable Specific Impulse Magnetoplasma Rocket (VASIMR). The technology was conceived by Franklin Chang-Díaz, an engineer, physicist and former NASA astronaut in 1975, for a vehicle that could cut down the time required for trips to Mars by half or more. The fuel is an inert gas such as argon, xenon, deuterium or neon, that is then heated to temperatures of the Sun by bombarding them with radio waves, with the plasma exhaust controlled using magnetic fields, to prevent the extreme temperatures from melting the nozzles.
The need for a power source
The biggest benefit of the technology is reducing the travel time for crewed missions to Mars, but the propulsion technology also has applications in Earth orbit and cislunar space. In 2006, NASA transferred the technology to the private spaceflight company Ad Astra Rocket, which has since then continued to develop the engine. The biggest roadblock for the innovative VASIMR propulsion technology is the power source required to heat the gas. This source has to be ten times more efficient than a nuclear reactor for say a nuclear-electric rocket, and has to be low-mass as well. The development of such a power source would be a breakthrough in itself, with a number of potential applications on Earth as well.
