Galactic Tech Empire

Chapter 240 Research Report
Although there are not a few countries with launch vehicle technology on Blue Star, the ones with relatively complete technology and a high degree of safety are Milijia, Maoxiong and Dongtang.

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

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

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

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

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

Usually a spaceship consists of two or three compartments, such as a crew compartment, a service compartment, and an orbital compartment.

The crew module is where the astronauts live and work during the flight. Except for the structure, it contains all the environmental control and life support systems.

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

The orbital module is mainly used to load various instruments.

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

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

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

The 280 cubic meter level has a mass of 34 tons, which obviously does not fully utilize all the 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 7790 kilograms.

That is to say, the volume of the initial model of the Shenzhou spacecraft is about 40 cubic meters, with an average 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 spaceship expert thought for a while and asked, "Academician Ma, what is the fuel and dead weight of your experimental spaceship?"

"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 that so?" The spaceship expert thought about it, and after a while, he said:
"Considering the further increase in the speed of the projected spacecraft, we must strengthen the structure of the spacecraft, otherwise the spacecraft may disintegrate because it cannot withstand too high a speed."

"This may be very large. After all, the spacecraft is at an altitude of 60 to 100 kilometers, and the atmospheric density is still relatively high. It is necessary to increase the heat insulation layer and strengthen the overall structure." Huang Haojie agreed with this possibility.

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

Hearing about graphene, carbon nanotubes and nanocomposites, Li Zhongting quickly asked a question:
"Using these materials, will the overall cost of the spaceship be too high?"

After all, things that are associated with terms such as nano, graphene, and carbon nanotubes are not cheap at first glance.

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

"More than a thousand times?"

Spaceship experts, Li Zhongting and others felt a lot of pressure. Even the space shuttle that Mi Lijia claims can be reused hundreds of times, the five space shuttles have not been used a hundred times in total, and there are two glorious ones during the period.

To design a spaceship that can be reused thousands of times is really difficult.

"I know this requirement is very difficult, but everything is difficult at the beginning. As long as you follow the goal, there are more solutions than difficulties." After Huang Haojie finished speaking, he selected a report from the spaceship model and sent it to everyone.

"This report is the result of Yinhe 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 prone failure of the spacecraft is the failure of the operating system, mainly because the electronic components are in outer space, affected by cosmic rays, and the aging and failure rates have risen sharply.

Whether it is Maoxiong or Milijia, their spacecraft have experienced control system failures many times, which led to accidents.

So what 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 the first artificial satellite of mankind - Sputnik1.

As a follow-up, Milijia also launched its first artificial satellite, Explorer 1958, in 1, which was equipped with a Geiger counter used to measure radiation dose intensity.

Van Allen issued after observing the radiation phenomenon around the earth: My God! Space is radioactive (to the effect: My God! Space is radioactive).

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

The Van Allen belts are divided into the inner belt and the outer belt. When the charged particles caused by cosmic rays or solar wind reach the blue star, they are bound by the Lorentz force under the action 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.

According to the size of the inner and outer belts, low-orbit 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 impact of electronically composed outer bands.

Radiation damage to spacecraft in outer space is ubiquitous.

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

Among them, a strong solar storm in 1989 caused 45 satellites to lose contact.

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

Near the South Atlantic Ocean in South America, there is a region with a weaker magnetic field of the earth. Due to the weaker magnetic field, its ability to bind charged particles is not strong, causing protons to be closer to the earth.

Low-orbit satellites passing through this region are more prone to failure.

The UoSat satellite manufactured by John's Surrey Satellite Company has recorded the anomalies caused by its passage over different earths, and the number of anomalies in the above-mentioned weaker regions of the earth's magnetic field is significantly more.

If the solar wind is considered, the charged particles ejected during the solar storm will seriously affect the original balance of the Van Allen belts.

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

Take the Beidou or GPS satellite navigation system as an example. On September 2017, 9, the sun erupted with the strongest flare in recent years. The ionospheric disturbance caused by it seriously affected the positioning results of ground navigators, and the positioning error of users was several times larger than before. times.

So, how does space radiation affect the safety of spacecraft.

According to the different mechanism of action, it 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 field effect transistors is easily affected by ionizing radiation. When a certain dose is reached, the device will fail.

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

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

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

So how do countries prevent or avoid the possible impact of space radiation on spacecraft?
At present, the 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 to vote, assuming that 3 of the 2 copies cannot be overturned at the same time, in exchange for the reliability of the system 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 space suits they wear are also designed to protect against radiation.

What was mentioned above is the situation of Raodi satellite or space station.

For deep space exploration, such as Cassini, which crashed into Saturn on September 2017, 9, or Voyager, which has already flown out of the solar system, it is more affected by cosmic rays, but the principle is the same.

(End of this chapter)