That's all future Martian colonists can eat? It seems that the food on Mars is not so good.

The goal of space exploration technology company is to help mankind build a city that can accommodate millions of people on Mars, but what do these people live on? (Photo: Space Exploration Technology Company)

How can we feed one million people on Mars? A new study has found that artificial meat, pipeline crops and cricket farms may solve this problem for us.

When it comes to the manned mission to mars program, NASA usually makes a round trip plan, with only a short stop on the surface of Mars. However, the goal of commercial space companies is to explore outer space, and the specific goal of space exploration technology companies is to establish human colonies on Mars.

For the long-term life on Mars, it is unrealistic to rely on the earth's supply spacecraft. The most practical strategy is to rely on the existing resources on Mars to survive. Researchers have determined that human beings need five consumable resources to survive on Mars, including energy, water, oxygen, building materials and food, and the first four resources may be very abundant on Mars.

For example, we have solar energy and maybe nuclear fission reactors, which can help provide energy for future Martians. Ice and water-bearing minerals on Mars are the source of water, carbon dioxide can be converted into oxygen, and Martian soil can also be easily made into bricks for building materials.

But in contrast, there is no natural food on Mars, and it is very difficult to use instruments (such as simple chemical reactors) to make Martian raw materials into food, the researchers said.

Keith Cannon, a planetary scientist in university of central florida, Orlando, the lead author of the research report, said in an interview: "Food is probably the most difficult thing to make locally on Mars. If you want to be self-sufficient, you can't rely entirely on imports. "

Faced with this challenge, scientists want to know how to achieve this radical goal and produce enough food for the 654.38 billion people on Mars.

Cannon said: "We have cooperated with many people who want to grow plants in our simulated Martian soil, which shows us the research that the scientific community is doing in producing food for future human landing on the moon or mission to mars. As it turns out, these studies mainly focus on very low-calorie vegetables, and they don't take into account the latest innovations that have replaced protein sources. We raised the question: Apart from the short-term mission of NASA, what is needed to support a city with a population of/kloc-0.00 million envisaged by Space Exploration Technology Company? "

The researchers pointed out that it is unrealistic to raise farm animals to obtain dairy products and meat on Mars in the short term, because transporting these animals to Mars will face many challenges. But at the same time, they also noticed that most people don't want to be completely vegetarian. Therefore, they think that cultivating meat in insect farms and laboratories will be the solution to this problem.

Researchers say that insect farms are very suitable for making Martian food because they can provide a lot of heat per unit of land with relatively little water and feed. At the same time, they also pointed out that crickets are one of the most promising examples of eating insects, and cricket powder may be included in many different recipes.

Cannon said: "If people can overcome psychological factors, then insects are the solution to this problem."

Researchers say that for those who don't like insects, "cell agriculture"-that is, food made from cells cultured in the laboratory-can help people on Mars eat some foods that they are more familiar with. Now, researchers say that everything is possible from seaweed to meat and fish, to milk-free and egg-free. After investors invested a lot of money to improve this technology, the cost of an artificial meat pie dropped from $325,000 to $65,438 +0 1 USD within two years.

When it comes to crops, researchers say that artistic illustrations of Mars settlements usually have greenhouses, but these greenhouses may not be practical. Because Mars is too far away from the sun, even at the equator with the most sunshine, the amount of light received by plants is similar to that received in Alaska. In addition, although the greenhouse is made of transparent glass windows, it usually absorbs 50-70% of the light on Earth, but on Mars, these glasses may only absorb more light, because the atmosphere of Mars is colder and thinner, so the greenhouse of Mars needs stronger materials to support the internal heating and pressure environment.

Researchers say that planting plants on Mars may require tunnels with high-intensity LED lighting. In addition, sunlight needs to be collected and transmitted through optical cables. They said that it is also possible to use hydroponics or air culture systems for soilless culture, but these strategies will require trays, pumps and water tanks, so we need to transport more materials to Mars. In addition, soil-based agriculture may be more resistant to diseases, but the researchers added that only after a lot of research and treatment can inorganic soil on Mars be transformed into living soil that can support plant growth.

Previous studies have shown that many crops may be particularly useful for Martian colonists, such as wheat, corn, soybeans, peanuts and sweet potatoes. Transgenic technology can also make crops help Martians in many ways-for example, consuming more carbon dioxide and increasing production.

Cannon said: "So far, almost all the research has focused on planting plants to feed astronauts, but plants will take up a lot of space. On another planet, this means building more large indoor factories that need pressure, heating and lighting. If you want to feed a large group of people on another planet, you must give up the idea of growing water-bearing vegetables and think about the large amount of energy, water and raw materials needed to produce enough heat. "

In order to understand what it may take to feed a Martian city with a population of one million, the researchers simulated a crowd model, including both immigrants from the earth and people born on Mars, with a birth rate of 25% per year (this is a typical birth rate in developed countries). In short, they assume that in a century, humans need to carry out 6,900 spacecraft missions and send about 1 10,000 immigrants to Mars, of which 340,000 were born on Mars.

Scientists calculated the calories needed by each person, and simulated the use of land by dietary conditions including wheat, corn, sweet potatoes, crickets and chickens raised in the laboratory. They found that a Mars colony with a population of one million could be built in 65438 by a vertical pipeline with a length of about 9,000 miles (14,500 kilometers) and a width of 12 feet (3.6 meters).

However, during this period, these colonists will need about 54,000 flights to import a lot of food. Scientists point out that there are actually many ways to greatly reduce the amount of imported food, such as speeding up the construction of farms on Mars.

Cannon said: "These studies have been widely questioned. People think this is the plot of science fiction-manned mission to mars will take decades to realize, so why bother to study this now? In fact, anyone who holds this view needs to take a serious look at what space exploration technology companies are doing-they are already testing the prototype of the Mars launch vehicle. "

He added that it was time to "find a way to achieve this goal".

Researchers say that research on how to feed Martian colonists can also help feed people on earth.

Cannon said: "The restrictions brought by the cold and thin atmosphere of Mars will force you to produce food in a more sustainable and ethical way than the existing factory farming methods on earth. Therefore, converting our current eating habits into' Martian eating habits' can also help our own planet. " To this end, scientists created a website, http://eatlikeamartian.org, to provide some related information.

The senior authors of the research report, Cannon and Daniel Britt of university of central florida, introduced their findings in detail in the online edition of New Space magazine on August 30th.