Every challenge that astronauts face on a flight to Mars (2023)

In 1972, the space race officially ended when NASA sent a final crew of astronauts to the lunar surface (Apollo 17). This was the brass ring that both the US and Soviets were reaching for, the "moon shot" that would determine who had supremacy in space. In the current age of renewed space exploration, the next big leap will clearly be sending astronauts to Mars.

This will present many challenges that need to be addressed beforehand, many of which have to do with simply getting the astronauts there in one piece! These challenges were the subject of a presentation by two Indian researchers at SciTech Forum 2020, an annual event hosted by the International Academy of Astronautics (IAA), RUDN University and the American Astronomical Society (AAS).

The study describing their research has recently appeared online and has been accepted for publication by Advances in Aeronautical Sciences (release date to be announced). Both the presentation and the presentation given at SciTech Forum 2020 were given by Malaya Kumar Biswal and Ramesh Naidu Annavarapua - a Postgraduate Researcher and Associate Professor of Physics at Pondicherry University, India (respectively).

Their research was also the subject of a presentation given during the seventh session of the Virtual Space Biology Workshop hosted by the Lunar Planetary Institute (LPI) and held January 20-21. As Biswal and Annavarapua have indicated in their studies and presentations, Mars holds a special place in the hearts and minds of scientists and astrobiological researchers.

Next to Earth, Mars is the most habitable place in the solar system (by terrestrial standards). Multiple lines of evidence accumulated over the decades have also shown that it may have supported life at one time. Unfortunately, sending astronauts to Mars inevitably comes with a variety of logistical and technological challengeshuman factorsand the associated distances.

Resolving these issues early is paramount if NASA and other space agencies hope to conduct the first manned missions to Mars in the next decade and beyond. Based on their analysis, Biswal and Annavarapu identified 14 distinct challenges including (but not limited to):

• The trajectory for Mars and corrective maneuvers
• Spacecraft and Fuel Management
• Radiation, microgravity and astronaut health
• Isolation and mental health issues
• Communication (in transit and on Mars)
• The approach to Mars and insertion into orbit

All of these challenges overlap to some degree with one or more of the other challenges listed. For example, an obvious problem in planning missions to Mars is sheer distance. Because of this, launch windows between Earth and Mars only occur every two years, when our planets are closest in their orbits (ie, when Mars is "opposite" relative to the Sun).

During these time windows, a spacecraft can make the journey from Earth to Mars in 150 to 300 days (about five to 10 months). This makes resupply missions impractical, as astronauts cannot wait that long to receive much-needed shipments of fuel, food, and other supplies. As Biswal emailed Universe Today, the distances involved also create issues when it comes to astronaut safety and power generation:

"In the event of an emergency situation, we cannot bring astronauts back from Mars [like we could] in the case of LEO or lunar missions... Likewise, the distance reduces the solar flux from Earth orbit to Mars orbit, resulting in a power generation deficit, which is very important for the." Propelling the vehicle and maintaining thermal stability (Again, the long distance can result in a low ambient temperature leading to hypothermia and frosting (especially in the mouth)."

In other words, the journey to Mars alone presents several specific challenges that Biswal and Annavarapu included in their analysis. Again, when it comes to astronaut health and safety, there are some specific challenges that come into play. For example, the fact that astronauts spend several months in space poses all kinds of risks to their physical and mental healthMental health.

For starters, there's the psychological toll of being locked in a cabin on a spacecraft along with other astronauts. There is also the physical toll of long-term exposure to a microgravity environment. As research aboard the International Space Station (ISS) has shown - particularly NASA's twin study - being in space for up to a year places significant stress on the human body.

In addition to the loss of muscle and bone density, astronauts who spent extended periods aboard the ISS also experienced vision loss, genetic changes, and long-term problems with their cardiovascular and circulatory systems. There have also been instances of psychological effects, with astronauts experiencing high levels of anxiety, insomnia, and depression.

But as Biswal said, the biggest and most obvious challenge is the total radiation (solar and cosmic) that the astronauts will be exposed to over the course of the yearMission:

“[The] greatest dangers include the risk of prolonged cancer and its effects due to exposure to both interplanetary radiation (during transit of Mars) and surface radiation (during prolonged stay on the surface). Then the effect of radiation causes defective brain coordination function and other brain diseases; then the psychological impact of the occupation during total isolation. Since the manned mission depends on the astronaut's performance, the astronauts have more health problems."

In industrialized nations, people on Earth are exposed to an average of about 620 millirems (62 mSv) annually, or 1.7 millirems (0.17 mSv) per day. Meanwhile, NASA has conducted studies showing how a mission to Mars would result in total exposure of about 1,000 mSv over a two-and-a-half year period. This would consist of 600 mSv over a year round trip, plus 400 mSv over an 18 month stay (while the planets realign).

That means astronauts will be exposed to 1.64 mSv per day during transit and 0.73 mSv for each day they are on Mars - that's about the 9.5 and 4.3 times the daily average. The health risks involved could leave astronauts suffering from radiation-related health issues before they even arrive on Mars, let alone the surface operations or the return trip.

Fortunately, there are mitigation strategies for the transit and surface portions of the mission, some recommended by Biswal and Annavarapua. "We are currently developing an underground Mars habitat that could address any health-related issues of extended mission or permanent colonization of Mars," Biswal said. "[T]he manned mission should include faster production of crew requirements from the in situ resource [utilization] (ISRU)."

This proposal is consistent with the many mission profiles NASA and other space agencies are developing for future exploration of the Moon and Mars. There are already many existing strategies to protect crews from radiation in space, but in extraterrestrial environments all concepts involve the use of local resources (like regolith or ice) to create a natural shield.

Local availability of ice is also seen as a must to ensure a steady supply of water for human consumption and irrigation (since astronauts on long-term missions must grow much of their own food). All that aside, Biswal and Annavarapu emphasized how maintaining a fast flight and return trajectory will help reduce travel time.

There is also the possibility of utilizing advanced technologies such as Nuclear Thermal and Nuclear Electric Propulsion (NTP/NEP). NASA and other space agencies are actively researching nuclear missiles because a spacecraft equipped with NTP or NEP could make the journey to Mars in just 100 days. But as Bisawl and Annavarapu have indicated, this raises the challenge of dealing with nuclear systems and increased radiation exposure.

Unfortunately, all of these challenges can be addressed with the right combination of innovation and preparation. And when you consider what it takes to send manned missions to Mars, the challenges seem a lot less daunting. As Biswal offered, these include proximity, the ability to study soil samples from Mars in an Earth laboratory, expanding our horizons, and being able to answer fundamental questions about life:

"We've always been fascinated to know where we come from and if there is life like us in other astronomical bodies? [We] cannot conduct a manned mission to another interplanetary destination due to mission risk and management.

"Mars is the only neighboring planet in our solar system that we can explore, it [has] a good geological record to answer all our unresolved questions, and [we can bring] samples [back] to use in our terrestrial laboratory." analyze? "And finally, it would be interesting to conduct a manned mission to Mars to demonstrate the magnitude of current technology and advances in aerospace."

Space agencies have been sending robotic missions to Mars since the early 1960s. Since the 1970s, some of these missions have been surface-landing landers. With over forty years of data and expertise resulting from this, NASA and other space agencies are now trying to apply what they have learned to send the first onesastronautsto Mars.

The first attempts may still be over a decade (or more) away, but only if significant preparations are made beforehand. Not only do many mission-related components and infrastructures still have to be developed, but also a lot of research still needs to be done. Fortunately, these efforts benefit from the kind of thorough assessments we see here, examining (and suggesting countermeasures) all potential risks and hazards.

All of this will hopefully lead to the creation of a sustainable program for exploring Mars. It could even allow for the long-term human occupation of Mars and the creation of a permanent colony. Thanks to the efforts of many researchers and scientists, the day may finally come when there are such things as "Martians."

More information:Interplanetary challenges encountered by the crew during their interplanetary transit from Earth to Mars.arxiv.org/abs/2101.04723