Space travel is an exciting prospect, but it also comes with a number of challenges. The main threats to human health and performance associated with space flight are radiation, altered gravity fields, hostile and closed environments, distance from Earth, and isolation and confinement. These five hazards have been studied by NASA's Human Research Program, which has observed that some participants soon experienced depression and mood swings, as well as hostility towards each other. This has caused some researchers to question plans to send only two astronauts to Mars in a single spaceship, as they may become bored, depressed, and even start to dislike each other.
Global dust storms occur every 5.5 Earth years (three Martian years) and could last for months. Although they are unlikely to cause serious physical damage to the seasons, they could cover solar panels and prevent sunlight from reaching Mars, endangering stations and astronauts. The levels of food and oxygen in the habitat are related because plants produce oxygen as a by-product. A study by MIT revealed that plants will produce excess oxygen if they produce enough food to feed all the inhabitants of the habitat.
This could be dangerous for astronauts as breathing excessive amounts of oxygen could kill them. The researchers suggest that this problem could be solved by developing an “oxygen removal system”. The race to take the first human to Mars is currently led by NASA, SpaceX and Blue Origin. All three organizations already have spaceships that could take us to Mars, but their rockets use dangerous fuels and would take too long to reach Mars from the point of view of human safety.
NASA is trying to solve this problem by developing the Space Launch System that uses liquid hydrogen and some other chemicals as fuel, while SpaceX is considering modifying its spacecraft to use liquid methane as fuel, and Blue Origin is making do with liquid hydrogen. As the possibility of carrying out long-term manned space missions to the Moon and even to Mars becomes a reality, scientists have begun to address the problems posed by surgery in space. The unique environment of space means that sick astronauts are more likely to die from injuries and minor infections there than on Earth. Astronauts sent to the International Space Station (ISS) are often trained to perform certain medical procedures, such as giving injections, stitching wounds and even extracting a tooth.
However, they would have to quickly return to Earth in a spaceship permanently docked on the ISS if they have more serious medical problems. This could be a big problem because a one-way trip to Mars could last six months. Solar storms are also unpredictable, making the situation worse. One solution is to develop a spaceship that can take astronauts to Mars much faster.
However, astronauts are not exempt from radiation risks even when they reach Mars. When finished, the MAV will weigh 18 tons and will carry an additional 33 tons of fuel for takeoff from Mars. This enormous weight means that it will not be able to land safely on Mars due to the planet's thin atmosphere, which could cause the MAV to burn up in the atmosphere or crash directly to the ground. To reduce weight, NASA has created a two-part system consisting of the MAV and an ERV (Earth Return Vehicle).
The MAV will take off from the surface of Mars and will transport astronauts to the ERV, which will return them to Earth. In space, the force of gravity is very low. These systems can often draw too much fluid from our legs and deposit it in the chest and head. Astronauts may then experience motion sickness, loss of balance, loss of taste and smell, and distorted vision due to fluid in their eyes.
Our bodies can adapt to this redistribution of fluid but it usually takes several weeks or months. Astronauts have encountered several constant medical problems during space flights including vestibular dysfunction, weight loss, height gain, upward fluid displacement, anemia, cardiovascular deconditioning, muscle atrophy, and bone loss due to the absence of gravitational force. Most are adaptive in nature and therefore reversible but readaptation after returning to Earth can cause more problems. The most recalcitrant problem is bone loss associated with a negative calcium balance which seems irreversible after two years in a state of weightlessness. Now moving on to more technical challenges, performance of propulsion systems is a major obstacle in space sector due to dangerous cosmic rays and irregular solar storms that could cause intense radiation.