The US space agency is planning to test inflatable spacecraft technology for future missions to Red Planet.For this, NASA scientists are considering to use a blow-up heat shield which resembles stacking ring of doughnuts that young children play with, Daily Mail reported.To begin with, the scientists aim to test how inflatable technology performs upon re-entry into the Earth's atmosphere.According to the team, a lightweight, inflatable heat shield could help a future spacecraft slow down enough to enter Mars' atmosphere at ease."We try to not use propulsion if we do not have to. We make use of that atmosphere as much as we can, because it means we don't have to carry all that fuel with us," Neil Cheatwood, NASA's senior engineer for advanced entry, descent and landing systems at their base in Langley, Virginia, was quoted as saying.The inflatables are made of lightweight material and filled with nitrogen.Once deployed for landing, the rings would sit on top of the spacecraft, resembling a giant mushroom.