Galaxy Technology Empire

Although there are many countries with launch vehicle technology on Blue Star, the only ones with relatively complete technology and high safety are Mi Lijia, Mao Xiong and Dongtang.

The difficulty of manned spaceflight technology is even higher than that of launch vehicles.

Although a spacecraft is the simplest type of manned spacecraft, it is still much more complex than unmanned spacecraft (such as satellites, etc.).

Spacecraft are similar to returnable satellites, but to carry people, many special systems must be added to meet the various needs of astronauts working and living in space.

For example, environmental control and life support systems, voice communication systems, instrumentation and lighting systems, space suits, manned maneuvering devices and escape systems for air renewal, wastewater treatment and regeneration, ventilation, temperature and temperature control, etc.

In addition, the spacecraft has basic structural systems, communication systems, power systems, temperature control systems, telemetry systems, attitude control systems, orbit change systems, propellants, etc.

Usually a spacecraft consists of two or three cabin sections, such as crew cabin, service module, orbital module, etc.

The crew cabin is where astronauts live and work during flight. In addition to the structure, it contains all environmental control and life support systems.

The service module is used to load various consumers and install attitude and orbit control system engines.

The orbital module is mainly used to load various instruments.

"I have seen your projector design model, which can accommodate a regular hexagonal cylinder spacecraft with a side length of 3 meters and a height of 12 meters. Is this size fixed?" A spacecraft design expert from a space agency spoke first.

Academician Ma replied: "The prototype is fixed, but we have improved the design. Taking into account the addition of vacuum pipes, the future projector guide rails will be movable. There are three specifications planned, each with a side length of 3 meters and a height of 3 meters. 12. The side length is 4 meters and the height is 16 meters, the side length is 5 meters and the height is 20 meters.”

Spacecraft experts calculated silently that the three specifications have about 280 cubic meters, 498 cubic meters, and 779 cubic meters of space respectively.

The 280 cubic meter level has a mass of 34 tons. This mass obviously does not fully utilize the entire space.

Taking the initial model of the Shenzhou manned spacecraft as an example, the parameters of the previous models are similar, with a total length of 8.86 meters, a maximum diameter of 2.8 meters, and a total weight of 7,790 kilograms.

That is to say, the volume of the initial model of Shenzhou spacecraft is about 40 cubic meters, with an average weight of about 200 kilograms per cubic meter.

The projection spacecraft with a volume of 280 cubic meters will reach about 56 tons based on the volume-to-weight ratio of the Shenzhou spacecraft.

The spacecraft expert thought for a while and asked: "Academician Ma, I wonder what the fuel and dead weight of your experimental spacecraft are?"

"The structure and equipment of the spacecraft itself are about 20 tons, the fuel and oxidizer are about 8 tons, the payload is 6 tons, and the remaining space is about 220 cubic meters." Academician Ma opened his notebook and replied.

"Is this so?" the spacecraft expert thought about it. After a while, he said:

"Considering that the speed of the projection spacecraft is further increased, we must strengthen the structure of the spacecraft, otherwise the spacecraft may disintegrate because it cannot withstand such a high speed."

"This is very possible. After all, the air density of the spacecraft is still relatively high at an altitude of 60 to 100 kilometers, so the heat insulation layer must be increased and the overall structure must be strengthened." Huang Haojie agreed with this possibility.

"Maybe graphene, carbon nanotubes and nanocomposites can be used to make the spacecraft to reduce the dead weight of the spacecraft." Li Xiang suggested.

After hearing about graphene, carbon nanotubes and nanocomposites, Li Zhongting quickly asked a question:

"With these materials, will the overall cost of the spacecraft be too high?"

After all, anything with the terms nano, graphene, and carbon nanotubes is not cheap at first glance.

"It doesn't matter if it's more expensive. The projection spacecraft itself is designed to be reusable. I'm considering that the projection spacecraft should be reusable at least a thousand times." Huang Haojie clicked on the display screen, and a model of a regular hexagonal cylindrical spacecraft emerged. .

"More than a thousand times?"

Spacecraft experts, Li Zhongting and others felt a lot of pressure. Even the Mi Li family's space shuttle claimed to be reusable hundreds of times, but the five space shuttles combined did not have a hundred times of use, and two of them were glorious during the period.

It is really difficult to design a spacecraft that can be reused thousands of times.

"I know this request is very difficult, but everything is difficult at the beginning. As long as you continue according to the goal, there are always more solutions than difficulties." After Huang Junjie finished speaking, he clicked out a report from the spacecraft model and sent it to everyone.

"This report is the result of Galaxy Technology's investigation and statistics of all space accidents around the world."

Everyone looked through it carefully, and as people from the space agency, of course they wanted similar research reports.

In fact, the most common failure of a spacecraft is the failure of the operating system. Mainly because electronic components are affected by cosmic rays in outer space, and their aging and failure rates increase sharply.

Whether it is Mao Xiong or Mi Lijia, their spacecrafts have experienced control system failures many times, leading to accidents.

So what exactly is the radiation received by spacecraft such as artificial satellites and space stations?

This starts with the "space race" of the last century.

In 1957, Lao Maozi launched mankind's first artificial satellite, Sputnik 1.

As a follow-up, Milijia also launched its first artificial satellite, Explorer 1, in 1958. This satellite was equipped with a Geiger counter for measuring radiation dose intensity.

After observing radiation phenomena around the earth, Van Alen issued: My God! Space is radioactive (to the effect: Oh my God! Space is radioactive).

Therefore, this radiation belt around the blue star is called the Van Allen Belt.

The Van Allen belt is divided into an inner belt and an outer belt. When the charged particles caused by cosmic rays or solar wind reach the blue star, they are affected by the Lorentz force under the influence of the blue star's magnetic field and are bound around the blue star.

The inner band is mainly composed of positively charged protons, and the outer band is composed of negatively charged electrons.

Depending on the size of the inner and outer belts, low-orbiting satellites or the International Space Station are located in the inner belt composed of protons.

Satellites such as Beidou or GPS navigation satellites, which mostly operate in higher orbits, are more susceptible to the influence of external bands composed of electrons.

Damage to spacecraft caused by radiation in outer space is common.

According to the document "Spacecraft System Failures and Anomalies Attributed to the Natural Space Environment" published by NASA, it introduces more than 100 cases of accidents caused by the space environment between 1973 and 1995. Spacecraft failure.

Among them, a strong solar storm in 1989 caused the loss of 45 satellites.

In addition, due to the uneven distribution of the earth's magnetic field, the radiation intensity in different areas of the earth is also different.

Near the South Atlantic Ocean in South America, there is an area with a weak Earth's magnetic field. Because the magnetic field is weak, its ability to bind charged particles is not strong, causing protons to get closer to the Earth.

Low-orbiting satellites passing through this region are more susceptible to failure.

The UoSat satellite manufactured by John's Surrey Satellite Company has recorded anomalies caused by its passage over different Earths. The number of anomalies occurred in the above-mentioned areas with weaker magnetic fields of the Earth was significantly higher.

If the solar wind is taken into account, the charged particles ejected during solar storms will seriously affect the original balance of the Van Allen belts.

During this period, satellite operations are more susceptible to charged particles.

Take the Beidou or GPS satellite navigation system as an example. On September 8, 2017, the sun erupted with the strongest flare in recent years. The ionospheric disturbance caused by it seriously affected the positioning results of ground navigation devices. The positioning error of users was several times larger than before. times.

So, how does space radiation affect spacecraft safety?

According to different mechanisms of action, they can be roughly divided into three types.

The first is called the "Total Radiation Dose (TID)" effect. Modern electronics use a large number of field effect transistors (MOS), and the gate oxide layer of the field effect transistor is easily affected by ionizing radiation. When a certain dose is reached, the device will fail.

The second type is called "displacement damage (DD)". When high-energy particles hit the crystal lattice, it will cause the position of the atoms in the crystal lattice to move.

This impact has the greatest impact on satellite solar panels, which can easily cause the efficiency of solar panels to decrease, eventually leading to insufficient power supply for satellites.

The third type is called "Single Event Event (SEE)". When high-energy particles hit a logic circuit, it is easy to cause the logic of the circuit to flip. If you are unlucky, it will enter an infinite loop.

So how do countries prevent or avoid the possible effects of space radiation on spacecraft?

At present, equipment on satellites and space stations is generally reinforced.

For example, in the design of "programmable logic gate array", a technology called Three Module Redundancy can be used.

It is to use 3 copies of the same device performance for voting. It is assumed that 2 of the 3 copies cannot be overturned at the same time, and the reliability of the system is exchanged at the cost of resources.

Of course, the space station will also use special materials to isolate and weaken space radiation.

Similarly, for astronauts performing missions in outer space, the spacesuits they wear are also designed to protect against radiation.

The above mentioned are all the situations of Raodi satellites or space stations.

For deep space exploration, such as the Cassini spacecraft that crashed into Saturn on September 15, 2017, or the Voyager spacecraft that has flown out of the solar system, they are more affected by cosmic rays, but the principles are the same.