NASA puts on a nuclear vessel to reach March in 45 days
B-wing with nuclear electric propulsion. © NASA/TIM Marvel
Among the many challenges that have been waiting for NASA since Donald Trump enjoined it to send men to March In the next four years, there is that of the duration of the journey. A nuclear electric propulsion ship project from the space agency, which hopes a prototype quickly, would shorten the path at 45 days instead of 200 usuals.
Perseverance, the last American machine to have made the Terre/March trip, traveled for seven months at the average speed of 39,000 km/h. She had for the occasion take advantage of a special launch window: when the two planets are closer to each other, every 26 months.
It is for this reason that a type mission touch and go (Place and leave) “Apollo” is impossible on Mars, because once arrived, the crew must wait for a complete terrestrial orbit to return to the fold. Otherwise, it will have 400 million kilometers to travel instead of sixty “only”. March, “It's beautiful, but it’s far”would have said a former president of the French Republic lover of apples …
In opposition to the sun, Mars is close to the earth. In conjunction in the sun, it is most distant from it. © NASA
A better propulsion system to reach Mars
The challenges imposed by so long journeys are multiple: solar cosmic influence, health of astronauts linked to weightlessness, common life in a limited space, quantity of food to transport. Likewise, the chemical fuel of “traditional” rockets weighs heavy and is ineffective in terms of weight/push ratio, even if it allows you to quickly reach a good speed of around 40,000 km/h. To go on Mars, it would take a lot, a lot of this fuel. This is where refueling problems often mentioned with starship arise, which must precisely test ergol transfers to terrestrial orbit this year.
Illustration of two starship spaceships moored one to the other in orbit to make a transfer of ergols. © SpaceX
Researchers from the NASA Langley Research Center in Hampton (Virginia) today explore the track of nuclear electric propulsion that ionise fuel (propergols). This type of system is called NEP (for Nuclear Electric Propulsion) and its great interest is to grant a push certainly low at the start, but whose acceleration will be continuous. Depending on the duration of the journey, the targeted speeds could easily reach 60,000 km/h or more. The project on which NASA works is called Marvl and obviously presents its constraints.
A ship built directly in space
Nuclear electric propulsion bi-wing prototype. © NASA/TIM Marvel
Such nuclear electric motor vessels are based on a fairly large heat dissipation system, radiator genres – because no, in space, no air that captures the calories emitted. There are currently on paper versions of these four radiators and two systems. One, called Quad-Wing, would be able to be integrated into a SLS rocket (the superlourd launcher developed for the Artemis program); The other, bi-wing, would officiate in commercial launchers. Heavier, more complex, quad-wing would require more fuel. Bi-wing would require several launches of commercial rockets and are assembled in space. This is the model that seems to hold the rope currently.
Remember that The International Space Station (ISS)which is today the size of a football field, has already been assembled in orbit. So that's something we know how to do. Here, assembly robots would be responsible for this task, in an impossor around the earth.
Quad-wing model planned to be launched by an SLS. © Eci Modular Assembled Radiators for Nep Vehicles (Marvl), An Overview by Stark et al. 2024.
Seduced, but pressed by time, NASA gave the team for two years to develop a demonstration prototype.
