When will humans live on Mars?

Mars is the closest planet to the Earth after Venus. Due to changes in its orbit, its distance from the Earth is between 55.7 million kilometers and 120 million kilometers. Mars is the planet with the environment closest to Earth that scientists have explored so far. If you are looking for another planet suitable for human habitation, Mars is definitely the first choice.

As humans have a deeper and deeper understanding of Mars, many scientists and even NASA have begun scientific exploration of immigrating to Mars. The American Mars Society has now formulated a detailed plan to transform Mars. Perhaps in 1,000 years, when the greenhouse effect finally destroys the earth, this plan will become mankind's "Noah's Ark."

Although humans have not landed on Mars yet and have only learned about the red planet at close range through detectors, human fantasies are endless. Currently, NASA's Mars landing plan has begun to be gradually implemented. According to the plan, American astronauts will land on Mars around 2030. In addition, Russia has also stated that it will send astronauts to Mars around 2015. These bold space programs will be the first step for humans to immigrate to Mars.

If you want to immigrate to Mars, you must first understand a concept - "terraforming the alien environment". This concept means "changing the alien environment, such as the gases in the atmosphere, to make it close to the natural environment of the earth." environment". If humans want to immigrate to Mars, the first and most important step is to generate oxygen on Mars for human survival. For this goal, many scientists believe that it will take 20,000 to 100,000 years. But Robert, the founder of the Mars Society, believes that this process actually only takes about 1,000 years.

It is reported that the Mars transformation plan formulated by the Mars Society led by Robert is divided into five steps. The most important of these is the first step - changing the environment of Mars. In order to achieve this step, the Mars Society has formulated three plans.

The first step: reaching the critical point of environmental terraforming

The first step in the specific plan to immigrate to Mars is to bring Mars to the critical point of environmental terraforming - to make this cold The planet is warming. Now, the temperature near the equator of Mars can sometimes reach above zero degrees Celsius. To completely melt the frozen material on Mars, the outer atmosphere of Mars needs to reach at least about 40 degrees Celsius. Unlike Earth, which is working hard to curb the greenhouse effect, Robert said humans will create a huge greenhouse effect on Mars. In Robert's plan, the time for completing this step is around 2150. The Mars Society has proposed three options for warming Mars, the third of which is endorsed by many scientists.

Option 1: Space mirror reflection

Create a space mirror with a diameter of more than 120 kilometers and orbit more than 21 kilometers from the surface of Mars. The space mirror will reflect sunlight onto designated areas of the Martian surface to release the atmosphere and water beneath the Martian surface. However, this space mirror is too big, and the current scientific level of mankind cannot build such a space mirror.

Option 2: Asteroid impact

Many asteroids in space are made of frozen ammonia, and ammonia is an important greenhouse gas. Robert's plan is to have an asteroid with a diameter of about 2.5 kilometers impact Mars. The huge energy generated by the impact will melt the ice on Mars into water, and the ammonia released after the impact of the asteroid can also significantly heat Mars. He estimates that 40 such impacts could bring Mars to a level suitable for human habitation. However, it is also very difficult to implement this solution.

Option 3: Create greenhouse gases

The third option is to artificially create greenhouse gases on the surface of Mars, which is considered the most feasible option. Like many scientists, Robert believes that carbon tetrafluoride is the most effective greenhouse gas. He plans to build several chemical plants on Mars to continuously produce carbon tetrafluoride. According to calculations, if 1,000 tons of carbon tetrafluoride are emitted per hour, the average temperature on the surface of Mars will increase by 27.8 degrees Celsius in 30 years. This process is expected to consume 5,000 megawatts of energy, and five nuclear power plants can meet these energy needs.

Step 2: Release the atmosphere in the Martian soil

Currently, there is only a thin atmosphere on the surface of Mars, but 3 billion years ago, the surface of Mars was surrounded by a thick carbon dioxide atmosphere. As Mars cools, most of the carbon dioxide is absorbed by the soil. When humans complete the first step of terraforming Mars, the warm climate will release this carbon dioxide. Robert said, "The carbon dioxide released from the soil can increase the temperature of Mars by another 5.6 degrees Celsius in 20 years. At this time, the melted water begins to evaporate and form weather phenomena such as rain and snow." According to calculations, by 2200, the surface of Mars will be Carbon dioxide has a pressure of 0.1 atmosphere.

Step 3: Build a closed city to plant plants

With the continuous release of carbon dioxide in the soil, by 2250, the atmospheric content on Mars will reach 0.21 atmospheres, equivalent to that of Earth One-fifth of it, most of it is carbon dioxide. At this time, Martian residents can go outdoors without wearing space suits, and of course they will need oxygen bags; ordinary airplanes can take off and land on Mars; people will also build a closed city with a dome. Once the temperature near the equator of Mars remains above zero degrees Celsius for many years, there will be a stable supply of liquid water on Mars.

By 2250, plants can already grow on Mars, but Robert said, "The first things to consider cultivating should be fungi and mosses that can promote photosynthesis."

Step 4: Plants generate oxygen through photosynthesis

The growth of plants means the production of oxygen. Photosynthesis gradually turns carbon dioxide into oxygen. In order to speed up the production of oxygen, Mars residents will plant various plants on a large scale and carefully handle all kinds of garbage, because the decay of garbage will produce a large amount of carbon dioxide. In addition, genetic engineering will help a lot, and Robert predicts that scientists will develop "super plants" that can release more oxygen.

Step 5: Work hard to "produce" more oxygen

The previous planning seems to be going smoothly, but what follows is a long process, because it is necessary to release Mars plants It will take about 1,000 years to produce enough oxygen for humans to breathe freely. During these 1,000 years, the residents of Mars will continue to plant and harvest, and strive to "produce" more oxygen.