Will humans set foot on Mars in 2020, 2050, or never? Predicting the timeline is becoming increasingly challenging. Intense radiation, bone loss in a weightless environment, deadly dust storms, and abnormal psychological states are just a few of the numerous challenges in this quest.
In the late 1990s, planetary geologist John Marshall began researching materials for astronaut suits to be worn during future Mars explorations. He tested these materials by placing them in a wind tunnel and spraying a mixture of red clay similar in composition to dust found on the Red Planet. The result was that the dust adhered tightly to the material’s surface, making it impossible to clean off. Thus, if astronauts were to wear suits made from these materials during missions, they would face numerous potential dangers. Mars dust clinging to their clothing could contaminate the spacecraft’s interior, corrode pressure seals, damage computer drives, short-circuit electronics, and even make crew members ill.
This is just the simplest example illustrating humanity’s vulnerability in the endeavor to conquer our “neighbor.” James Garvin, head of NASA’s Mars exploration program, admits that the greatest challenge is that they can never be certain about what is happening on this planet.
Thirty years ago, the success of the moon landing program led us to believe that conquering the planets in the solar system would not be too difficult. At that time, space engineers hoped that a manned mission to Mars would be feasible by 1981. However, after more than 20 years, the most valuable lesson NASA has learned is that any rush to the finish line will only result in catastrophic failure. For instance, during the 1970s, engineers would have confidently chosen aluminum as the material for spacecraft hulls to block harmful radiation. Yet recent studies have shown that aluminum atoms can be destroyed by cosmic rays, thereby making aluminum shielding a potential risk to the crew.
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Earth’s Neighbor |
The time required for a Mars expedition also poses significant obstacles. While a lunar mission might take about a week, a mission to “the God of War” could span up to three years. Such an extended duration in space requires scientists to develop measures to protect the crew’s physical and mental health, devise equipment suitable for Martian conditions, and ensure the availability of spare parts and repair options in case of malfunctions. They must also secure sufficient supplies of food, water, and other essentials, as resupply from Earth is not an option.
Although the progress toward Mars has not kept pace with scientists’ initial expectations, the race to conquer this planet remains fierce. Recent scientific discoveries have opened many possibilities. Data collected by the Mars Odyssey spectrometer indicates that there may be water beneath the Martian surface, which suggests the potential for life or at least traces of life in the past. Meanwhile, geologists are eager to understand how Mars became so dry and whether the planet holds clues about Earth’s future. An expedition could provide an opportunity to test the viability of human existence under conditions beyond our blue planet.
After the Columbia disaster in February, NASA’s plan for 2020 was limited to sending orbiters, rovers, and a few prototype devices to Mars. However, the budget NASA proposed for space research in 2004 was $4 billion, an increase of $532 million from 2003, with part of that surplus allocated for experimental programs aimed at solving issues related to Mars exploration.
Launch Vehicles
In 1969, Apollo 11 was launched to the moon using the massive Saturn V rocket. However, for the current Mars conquest needs, this type of rocket is insufficient. To cover the distance 200 times that from Earth to the moon, the fuel compartment of the spacecraft would need to be so large that it would be impossible to create a vehicle powerful enough to launch it from Earth’s orbit.
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Bekuö Spacecraft |
NASA has proposed a $3 billion investment over the next five years for the Prometheus project, aimed at seeking new energy sources and developing propulsion systems that meet Mars exploration requirements. This project will initially launch two unmanned spacecraft: one powered by radioactive isotopes scheduled for a Mars mission in 2009, and another running on nuclear electricity to be launched to Jupiter in 2011. NASA is also developing a system called the Variable Specific Impulse Magnetoplasma Rocket (VASIMIR) to be tested on a spacecraft named Bekuö. Designed to use hydrogen energy, Bekuö aims to transport the crew to Mars within 90 days, reducing travel time by one-third to one-half compared to current technology.
Regardless of the engine type chosen, it is certain that the Mars-bound spacecraft will be assembled in space, as launching from the vacuum of space is significantly more fuel-efficient than launching from the ground. The International Space Station (ISS) currently under construction demonstrates that spacecraft assembly in space is feasible, but NASA will require a shuttle to transport components to the ISS efficiently, safely, and economically.
Once on Mars, astronauts will need a power supply to maintain life support and research activities. If solar panels are not the most effective solution, NASA may have to turn to nuclear energy.
According to data recorded by the Mars Odyssey during its orbit around Mars from 1999 to 2001, radiation levels on the Red Planet are about 20-25 millirads per day, which is double the permissible dose for workers in nuclear plants in the U.S…
Moreover, radiation levels will be even higher during the journey from Earth to Mars and back. Cosmic radiation—energy and particles primarily emitted by the sun—can adversely affect and even break DNA chains in cells, triggering cellular mutations that may lead to leukemia and various other cancers over time. Although the human body has mechanisms to repair DNA abnormalities, the high radiation levels in the Martian environment could exceed the body’s natural repair rate.
Scientists are also very concerned about the widespread presence of high-energy cosmic rays in space. These rays can emit radiation in sufficient quantities to cause damage to the central nervous system, such as impairing the motor and cognitive functions of astronauts. A study conducted by NASA two years ago also indicated that astronauts spending extended periods in space would have an increased risk of developing cataracts, a consequence of radiation exposure. Because of the health risks posed to astronauts, NASA limits the maximum time spent in space to 250 days, approximately the minimum duration required for a round trip to Mars.
Health
During long journeys in space, astronauts experience bone density loss at a rate of 1-2% per month. It is currently unclear whether the weightless environment slows this process, but in the worst-case scenario, astronauts on a three-year mission to Mars could lose half their bone mass, making their bones brittle, more prone to fractures, and slower to heal after injury.
There are also many indicators that the immune system’s ability declines significantly during space flights. Studies on Earth show that the immune activity of cells decreases by nearly 50% after each flight. However, these findings are based on Earth research, so scientists cannot accurately predict how the immune system will react when the body is in space for prolonged periods. When the immune system is weakened, even a common illness can have severe consequences, and latent diseases in the body, such as chickenpox or shingles, may reactivate. To detect and prevent outbreaks early, scientists propose extremely small devices to monitor cells. When signs of abnormalities are detected, these devices will issue alerts for astronauts to take medication promptly.
The Psychology of the Crew
Confined in a cramped space for years in a location far from Earth, where communication takes 20 minutes, the feeling of isolation can make astronauts prone to agitation and mental distress. Because it is impossible to recreate the harsh psychological environment of Mars in terrestrial experiments, scientists cannot accurately predict the endurance of astronauts. NASA is researching whether it can mitigate potential conflicts among crew members by selecting individuals with compatible personalities. NASA also hopes to design a monitoring computer that can detect stress levels and unusual mental health signs through changes in facial expressions and vocal intensity, allowing for appropriate calming measures.
The Environment on Mars
Contrary to its name, the Red Planet is extremely cold. In 1997, the Pathfinder probe measured temperatures at the landing site ranging from -13 degrees Celsius to -93 degrees Celsius over 24 hours. Mars is not only frigid but also experiences numerous dust storms that can generate static electricity with voltages up to 8 kV, strong enough to damage computers and blow fuses.
The atmosphere, dense with carbon dioxide and lacking water, makes Mars uninhabitable. Meanwhile, transporting water and air reserves to this planet is quite challenging, so astronauts are likely to bring devices that contain hydrogen to convert atmospheric carbon dioxide into methane and water. Subsequently, the water will be electrolyzed to separate it into oxygen and hydrogen. The oxygen will be used for breathing, while the hydrogen will be recycled for further use.
Although NASA is focused on developing technologies to assist the journey to Mars, many risks remain beyond human prediction. Experts estimate that the risk of a Mars expedition is 25%, meaning that one in every four missions to this planet may result in a crew not returning. This is the same risk rate that NASA predicted for the Apollo program during lunar exploration missions. However, a journey to Mars will be much longer and more complex than a trip to Earth’s satellite. Therefore, the final and most critical question is whether NASA dares to take the risks to pursue the ambition of conquering the distant Red Planet.
Initiated over 20 years ago, NASA’s Mars research program has only progressed to sending unmanned probes to the Red Planet. So how much longer must humanity wait?
Robert Zubrin, President of the Mars Society: “If NASA had continued the Apollo program, the first children born on Mars might have been ready to graduate from high school by now.”
Buzz Aldrin, a member of the Apollo 11 crew: “From the first airplane of the Wright brothers to humans landing on the moon, it took exactly 66 years. Therefore, the transition from lunar missions to Mars missions will take about the same amount of time.”
John Charles, Senior Scientist at NASA: “Before the Columbia disaster, I believed we would reach Mars within the next 20 years. But now I can no longer be as optimistic as before.”
Roger Launius, Professor of Space History at the Smithsonian National Air and Space Museum, Washington, D.C.: “We (Americans) conquered the moon for many political reasons, the most important being the race against the Russians during the Cold War. Today, it is hard to find a strong political motive to accelerate our Mars exploration efforts.”
