In a recent exchange, NASA Administrator Jim Bridenstine discussed the various upcoming projects, including the Mars 2020 and Artemis missions. He also took the opportunity to take stock of the various preparations underway as part of a future human exploration of the red planet.
As American astronauts prepare to walk again on the Moon as part of the Artemis missions, several public agencies and other private companies are also eyeing another target: Mars. This is particularly the case of SpaceX, or even NASA, which is planning a first crewed mission in the 2030s.
Obviously, exploring Mars with rovers is one thing, but sending humans there is another. Especially since then you must be able to bring them back to Earth safely. In this sense, the American agency is already working on the development of several technologies capable of meeting these various objectives.
More powerful propulsion systems
Astronauts to Mars will have to travel approximately 140 million kilometers in deep space. With our current propulsion systems, such a trip would take between six and nine months. The agency and its partners are currently developing, testing, and maturing various technologies with the aim of reducing this travel time. Enough to minimize the exposure time of astronauts to cosmic radiation. It is still too early to say which propulsion system will be chosen, but it seems that NASA has opted for nuclear thermal propulsion.
The idea here is to heat liquid hydrogen to a very high temperature by means of a nuclear reactor. The material is then ejected from the rear of the rocket (via a nozzle) to create a thrust. Various configurations have already been proposed since the beginning of the space age, but so far, no rocket using this type of propulsion has yet managed to fly.
An inflatable heat shield to land the astronauts
The biggest rover ever to land on Mars is the size of a small car. On the other hand, if we want to deposit astronauts on the surface, we will have to think bigger, and therefore heavier. The inflatable heat shield is one of the solutions NASA has devised to bring in this type of load. When expanded and inflated, this shield would allow entry and passage through the Martian atmosphere to safely disembark cargoes and astronauts.
The technology is not ready yet, but engineers at NASA have been working on it for a few years now. It is also expected that a prototype 6 meters in diameter will soon be deployed above the Earth’s atmosphere.
They are essential. True personalized spaceships, the combinations currently developed in the context of the next lunar missions – safer, more efficient, and more comfortable than the previous ones – will be the same as those then deployed on Mars.
NASA, on the other hand, is planning several upgrades, mainly to combat heat stress. These future suits must indeed be able to keep astronauts warm during the Martian winter and avoid overheating in summer.
To reduce the quantities of payload, NASA, at least initially, will favor the “two in one”. The agency plans to evolve its astronauts in a sort of space “camper van”. In other words, in a pressurized habitat mounted on wheels and able to move as needed.
Inside, astronauts will have what they need to live and work for weeks on end. They will also be able to pilot the machine in comfortable clothing for tens of kilometers. If necessary, they can also put on their spacesuits to get out of the rover and collect samples or conduct scientific experiments.
NASA has already carried out several tests on Earth to inform the development of such a “mobile home” for future lunar missions. The return of the Artemis program astronauts operating in this future pressurized rover will obviously be taken into consideration to improve the technology.
The energy problem
There, astronauts will need a reliable power supply to explore the planet. The system will need to be lightweight and able to operate regardless of its location or the weather on the Red Planet. And it will not be easy. As a reminder, Mars is indeed prone to dust storms which, at times, can last for months.
Martian astronauts will be able to rely on lasers to stay in contact with ground operators. This type of system promises to send large amounts of information and data in a relatively short time, unlike various radio systems. We could then communicate with the astronauts almost in real time and enjoy high definition video streams.
NASA has already proven the viability of such laser communications with a demonstration from lunar orbit in 2013. The agency is now working to refine the technology. It is normally planned to do several tests from the International Space Station (ISS) and as part of Artemis missions.
Finally, a payload is expected to venture into deep space soon to test the technology millions of kilometers from Earth.