The expedition was not so boring, and soon, after 38 days of sailing, the Prince Barnett reached the designated airspace and began to slow down.

It is still more than 7 million kilometers away from the meeting point of Prince Barnett and Mars.

In fact, if you don't take into account the deceleration of the spacecraft, then the "Prince Barnett" only needs 43 days to reach Mars, but unfortunately, if the "Prince Barnett" does not slow down, then it will directly pass Mars and rush farther into space.

Because Mars has a much smaller mass than Earth, Mars also has a much lower escape velocity than Earth. In order to escape the gravitational pull of the Earth, the velocity must reach the second cosmic velocity, which is 11.2 km/s, and the escape velocity of Mars is only a little more than 5 km/s, which is not even as good as the first cosmic velocity.

The expedition to Mars is different from the expedition to the moon, Mars revolves around the sun at high speed, and the orbital speed of Mars around the sun is as high as 24 km/s, not to mention the "Prince Barnett", even any spacecraft on the earth cannot reach such a fast speed. Therefore, to expedition to Mars, it is necessary to calculate the route of the spacecraft and the speed of Mars, so that the spacecraft can meet Mars when Mars arrives at a certain location.

Therefore, if the "Prince Barnett" wants to successfully land on Mars, it must reduce its forward speed before the Mars convergence, and then let the Martian gravity capture the "Prince Barnett" when it converges with Mars, so that the "Prince Barnett" can orbit Mars and then land on Mars.

Therefore, when the "Prince Barnett" is still some distance from the rendezvous with Mars, it must start slowing down. It was only because it was easy to speed up and difficult to slow down, so the spacecraft had to start decelerating thirteen days in advance in order for the "Prince Barnett" to reduce its speed to the specified speed at the meeting point.

Although the auxiliary ion engine compartment in the bow of the "Prince Barnett" has also been replaced with three large-caliber ion engines, and the main ion engine compartment at the stern uses the same power ion engine, the spacecraft is easy to accelerate, but it is very difficult to slow down.

Because there is almost zero gravity in space, it is difficult to slow down any object when it is moving at high speed in space. Even the "Prince Barnett" had three large-caliber ion engines and four recoil rockets on board.

And the most important thing is that in order to slow down the precision "Prince Barnett", it is necessary to consider whether the vibration caused by the deceleration will cause damage to the hull of the spacecraft, so excessive deceleration is not advisable, and the spacecraft can only be slowed down, so this deceleration will take up to thirteen and a half days, and the deceleration distance will exceed seven million kilometers.

It can be said that the whole deceleration process is even more complicated than that of the "Starry Sky 5" launch, and if you are not careful, either the speed of the spacecraft does not decrease to the specified speed when it reaches the meeting point and passes by Mars, or the spacecraft slows down too fast, so that it cannot reach the meeting point at the specified time.

In any case, the thirteen-and-a-half-day deceleration process is the most difficult stage of the entire manned Mars exploration program.

Although the main control computer on the "Prince Barnett" has unparalleled computing power, the computer is always a computer, and it can never be compared with the human brain in terms of judgment and execution, so after spending more than 30 days of leisurely and somewhat boring days, all twelve astronauts, including Tang Feng, all raised their spirits to cope with the spacecraft deceleration process.

This is the first time that human beings should slow down a spacecraft at such a high speed, and it must also meet Mars, which orbits the sun at high speed, at the right time, and control the speed at which the "Prince Barnett" cuts into the orbit around Mars at the time of the rendezvous.

If you can't do it, I'm sorry, this manned Mars exploration program that cost Tang more than $150 billion in funds will be directly GAME-OVER.

Eleven astronauts were divided into three shifts and began to take turns monitoring the deceleration of the spacecraft. Although Tang Feng also has the heart to help, he is really a mallet in this regard, it's okay not to help, the more he helps, the more he helps. So Tang Feng simply stopped working and continued to make soy sauce.

Anyway, these eleven astronauts have also conducted several simulated training on deceleration in the training camp on Earth, and they have done a good job, and Tang Feng also believes that they will control the spacecraft in the real deceleration process.

When Prince Barnett began to slow down, Mars was still 27 million kilometers away from the meeting site, but Mars' orbital speed was as high as 24 kilometers per second, and the distance of 86,400 kilometers in an hour would be 86,400 kilometers, so after thirteen and a half days, Mars, which looks smaller than a glass sphere here, will arrive at the meeting point on time.

In command chief Han. At Zheng's command, the three 1800 mm ion thrusters in the bow of the ship began to operate at full capacity, and as the output of the ion thrusters reached their maximum power, the speed of the "Prince Barnett" began to decrease at an extremely slow speed.

Of course, while the ion thrusters in the bow of the ship are working, some of the nozzles in the hull also begin to work under the control of the computer, and as long as the flight attitude of the hull changes slightly, then the gas ejected from these nozzles can adjust the flight attitude of the hull back.

This process is similar to the process of vertical recovery of the "Starry" series of heavy-lift launch vehicles, except that at this time, the speed of the "Prince Barnett" far exceeds the falling speed of the first-stage core rocket of the "Starry" heavy-lift launch vehicle in the earth's atmosphere. Of course, because it is in a vacuum, the adjustment of the flight attitude of the "Prince Barnett" is far easier than that of the "Starry Sky" heavy launch vehicle.

Facts have proved that the main control computer on the "Prince Barnett" is still very passable, the powerful computing power allows the main control computer to control the flight attitude of the spacecraft very well, and with the start of several more thrust recoil rockets, the "Prince Barnett" finally reduced the speed to the specified range within the specified time, and successfully cut into the orbit around Mars.

At this time, Mars, which had been flying in space for thirteen and a half days, has also changed from a small glass sphere 27 million kilometers away to a huge planet full of red (to be continued). )