Little scientific knowledge about rockets

1. Little knowledge about aerospace science and technology

1. The characteristics of electronic equipment on aerospace vehicles are:

① Small size, light weight and low power consumption are required ; ② Able to work under harsh environmental conditions; ③ High efficiency, high reliability and long life. On high-performance aircraft and spacecraft, these requirements are particularly stringent. The cabin volume, load capacity and power supply of aircraft and spacecraft are strictly limited. For every 1 kilogram increase in the weight of the equipment on the satellite, the launch weight of the launch vehicle will increase by several hundred kilograms or more. Missiles and spacecraft must withstand severe impact overloads, strong vibrations, and particle radiation. Some spacecraft have a very long working time, such as geostationary communication satellites, which last for 7 to 10 years, while deep space probes work for even longer. Therefore, electronic components used in aerospace must undergo extremely strict quality control and screening, and the design of electronic systems requires full use of reliability theory and redundancy technology.

2. The main development directions of aerospace electronics technology are:

① Make full use of electronic computers and large-scale integrated circuits to improve the integration, automation and intelligence of aerospace electronic systems level; ② Improve real-time signal processing and data processing capabilities and data transmission rate; ③ Develop high-speed and ultra-high-speed large-scale integrated circuits; ④ Develop electronic technology in higher frequency bands (millimeter waves, infrared, optical frequencies) ;⑤Develop various electronic components with higher reliability and longer life.

2. Knowledge about rockets

Rocket Encyclopedia Business Card A rocket is a jet propulsion device that ejects hot air backwards at high speed and uses the reaction force generated to move forward. It carries its own combustion agent and oxidant and does not rely on oxygen in the air to support combustion. It can fly in the atmosphere and in outer space. Modern rockets can be used as vehicles for rapid long-distance transportation, such as sounding, launching satellites, manned spacecrafts, space stations, and boosters for other aircraft. If it is used to deliver warheads (warheads) for combat purposes, it constitutes a rocket weapon. Among them, those that can be guided are called missiles, and those that are unguided are called rockets. There is a basketball team with the same name, named after its city, Houston, which is the center of American aerospace technology. Table of Contents [Hide] Basic introduction History Origin of Rockets Hometown in China Regulations Classification and composition Current status and development Simulated rockets Launch records of various countries around the world Explanation of words Carrier rockets Space rockets Meteorological rockets Modern rockets Milestones Rocket launchers Multi-stage rockets NBA team Snooker players Basic introduction History Origin Rocket’s hometown in China Regulations Classification and composition Current status and development Simulated rocket Launch records of various countries around the world Word explanation Launch vehicle Space rocket Meteorological rocket Modern rocket Milestone Rocket launcher Multi-stage rocket NBA team Snooker player [Edit this paragraph] Basic introduction to rocket It is currently the only vehicle that can enable objects to reach cosmic speed, overcome or escape the gravity of the earth, and enter cosmic space. The speed of a rocket is obtained by the work of the rocket engine. As early as 1903, Tsiolkovsky derived the ideal speed formula for a single-stage rocket: V=ωLnMo/Mk, which is called the Tsiolkovsky formula. ω is the jet speed of the engine, Mo and Mk are the initial mass of the rocket and the mass when the engine stalls (the propellant is used up) respectively. Mo/Mk is called the mass ratio of the rocket. It can be seen from this formula that the speed of the rocket is directly proportional to the jet speed of the engine and increases as the mass ratio of the rocket increases. Even if the best-performing liquid hydrogen and liquid oxygen propellants are used, the jet speed of the engine can only reach 4.3~4.4 kilometers/second. Therefore, it is impossible for a single-stage rocket to send objects into space orbit. Multi-stage rockets must be used to send spacecraft into space orbit in a relay manner. Rockets used to carry spacecraft are called space launch vehicles, and rockets used to carry military bombs are called rocket weapons (uncontrolled) or missiles (controlled). Space launch vehicles generally consist of power systems, control systems and structural systems, and some also add telemetry, safety self-destruction and other additional systems. The connection methods between the stages of multi-stage rockets include series connection, parallel connection and series-parallel connection.

Series connection means connecting several single-stage rockets in series in a straight line; parallel connection means placing a larger single-stage rocket in the middle, called the core stage, and bundling multiple smaller rockets around it, generally called booster rockets. Or booster, that is, booster stage; the core stage of a series-parallel multi-stage rocket is also a multi-stage rocket. The connection and separation between the stages of the multi-stage rocket, between the rocket and the payload and the fairing are achieved by connecting a separation mechanism (often referred to as the separation mechanism). The separation mechanism consists of an explosive bolt (or explosive cord) and an ejection device (or small rocket). Normally, they are connected as a whole by explosive bolts or explosive cords; when separated, the explosive bolts or explosive cords explode to unlock the connection, and then the two parts are separated by an ejection device or a small rocket, or with the help of the front-stage rocket engine started Powerful jet separates. Rocket technology is a very complex comprehensive technology, which mainly includes rocket propulsion technology, overall design technology, rocket structure technology, control and guidance technology, plan management technology, reliability and quality control technology, and test technology. It is also important for missiles. There are warhead technologies such as warhead guidance and control, penetration, re-entry thermal protection, nuclear hardening and miniaturization.

3. Scientific and technological knowledge about rocket structure

The basic components of a rocket include the propulsion system, rocket body structure and payload.

Controlled rockets are also equipped with guidance and control systems, and sometimes telemetry, safety self-destruction and other additional systems can be installed on the rocket as needed. The propulsion system is the source of power for rocket flight.

The propulsion system of a solid rocket is a solid rocket motor. The propulsion system of a liquid rocket includes an engine, propellant tank, pressurization system and pipeline valve group (see aircraft propulsion system).

The function of the rocket body structure is to load all the components of the rocket to form a whole. Usually the casing of the solid rocket motor and the box of the liquid rocket form part of the rocket body structure.

In addition, it also includes the tail section, interstage section, instrument cabin structure and payload fairing. The rocket body structure should have good aerodynamic shape.

On the premise of completing the same function, the smaller the weight and volume of the rocket body structure, the better. In order to reduce the weight of the rocket body structure, in addition to design skills and process methods, the selection of structural types and materials is also very important.

The payload is the object that the rocket is intended to transport. Rockets serve different purposes and have different payloads.

The payload of a military rocket is the warhead (warhead). The payloads of scientific research rockets are various research instruments.

The payload of the launch vehicle is spacecraft such as artificial satellites, manned and unmanned spacecraft or space probes.

4. Popular science knowledge about aerospace

July 24, 33 years ago, was a big day, because American astronauts landed on the moon for the first time and returned to Earth on July 20.

However, some people have always said the opposite, saying that humans have never landed on the moon. Those photos and videos of astronauts walking on the moon and planting American flags are all "moon landings" created by NASA. Scam" and even claimed to have found the mastermind behind it! Regardless of which is true or false, the debate continues to this day. Since the moment astronaut Armstrong first landed on the moon on July 20, 1969, conspiracy theories have been circulating, questioning whether the moon is fake and is just the desert of Nevada in the western United States or a Disney movie studio. The light and shadow on the surface are just movie spotlights, etc. All scenes related to the moon landing in the 1960s and 1970s are the "Moon Hoax" released by NASA.

The "moon landing hoax" that the national flag will move even if there is no wind has been popularized again in recent years. Famous writers and TV programs have used it as a topic. Even Fox Work in the United States last year A special program was also filmed to explore whether American astronauts had actually landed on the moon, making the "moon landing hoax" a hot topic again. Supporters of the "moon landing hoax" conspiracy theory raised many doubtful points, which caused an uproar in the outside world for a time because of their reasonableness. However, some people later refuted them point by point in order to clear the innocence of the human landing on the moon.

One of the most famous doubts raised by conspiracy theorists is that the American flag planted by astronauts on the moon. If the flag still swings for a long time after letting go, it means that there is wind at the scene, that is, there is air, indicating that the astronauts Being on earth. But the rebuttal explained that the flagpole was made of aluminum and gold and was L-shaped.

When the astronauts place the flag, due to the hard moon geology, they have to twist hard to put the flag. Therefore, this twisting plus the vibration caused by the elasticity of the flagpole itself causes the flag to swing. . According to Newton's first law of mechanics, "What moves is always in motion, and what is still is still." In a vacuum environment, without the buffer of air, the national flag can swing for a long time without stopping.

High temperatures do not hinder photography. Conspiracy theorists have also questioned the collapse of moon landing photos, because the different lengths of the astronauts’ shadows and the reflection of strong light from close range by objects indicate that there is more than one light source at the scene. They said that since there is only one light source on the moon's surface, the sun, and it is not illuminated at close range, another light source must come from the spotlights used for the scene, which proves that the moon landing was fake.

But this statement was denied again. The rebuttal explained that the uneven surface of the moon formed shadows of different lengths. They also questioned that it is impossible to film on the moon because under direct sunlight, the temperature can reach as high as 250 to 280 degrees Fahrenheit (approximately 121 to 138 degrees Celsius), and the film has already dissolved.

However, they had no idea that the astronauts used special film. In fact, the arguments put forward by conspiracy theorists often rely on their limited understanding of photography as a medium and their partial knowledge of the moon landing plan, so other doubts they raised have been refuted one by one.

The Soviet Union will definitely expose it. Professionals say that the "Moon Landing Hoax" is not credible because the United States and the Soviet Union were sworn enemies at the time. The Soviet Union has been closely monitoring every step of the Helios Plan. If it finds anything wrong, it will immediately expose it. U.S. Wong Yao-wa, assistant director of the Hong Kong Space Museum, pointed out, "The United States and the Soviet Union were in the Cold War at the time. If the United States cheated, the Soviet Union would definitely take the opportunity to expose it. Moreover, the Soviet Union had an unmanned spacecraft on the moon. If it was a scam, the Soviet Union would not be able to detect it!" Another ironclad fact is that the United States really took the moon rock back to the earth. "That moon rock will be given to scientists around the world for research. If it is fake, it will be revealed early on."

Some opponents of the "conspiracy theory" said: "These ridiculous remarks are an insult to those who have sacrificed their lives to land humans on the moon!" One of the behind-the-scenes hype men who wrote a book about the "moon landing scam", the father of the scam, said The man is Bill Kaysing, known as the "Father of the Moon Landing Hoax". He and David Percy, a British photographer, wrote the book "We Never Went to the Moon" (We Never Went to the Moon). Bill Kaysing worked for Rocketdyne, one of the lunar module manufacturers, in 1957. Although he left before the start of the Apollo program in 1963, he claimed to be familiar with the details of the Apollo scam.

However, the question about the authenticity of the photo shows that he is a complete layman on photography technology. In order to strengthen the credibility of his work, he claimed to have invited a number of anonymous experts to assist.

In addition, David Percy, a member of the Royal Photographic Society and a photographer, pointed out the flaws in the moon landing photos as a photography expert; however, David has also been criticized by outsiders for not understanding photography skills. Other proponents of the moon landing hoax include journalist Bart Sibrel, who claimed to have photographed the astronauts on Apollo 11, who made fake footprints inside the spacecraft, and self-taught engineer Ralph Rene.

The doubts are dispelled one by one to support the "moon landing hoax" arguments 1. After the astronauts let go, the flag pole still swung for a long time. 2. In the TV transmission screen of Helios 17, two astronauts were in the frame at the same time, but the two shadows were different lengths and pointed in different directions, proving that there were different light sources at the scene.

3. When Apollo 16 astronaut John Young stood on the moon and saluted the flag, there were no stars in the background, and there was no shadow of him.

4. In the photo, there seems to be a C character on a rock in the close-up view, which is clearly a movie prop.

5. In the transmission pictures of Helios 14 and 17, the astronauts’ light-shielding masks reflected a lot of strong light. That was the reflection of the spotlights, which proved that the scene was just a set. Arguments to refute the "moon landing hoax" 1. When the astronauts planted the flag, they twisted it hard. The twisting and the vibration caused by the elasticity of the aluminum flagpole itself caused the flag to swing.

In a vacuum environment, without the buffer of air, the flag can swing for a long time. 2. The surface of the moon is uneven, so the shadows appear to be of varying lengths.

The Hasselblad camera used by astronauts, equipped with a 60mm Bio-Gon wide-angle lens, will also distort the originally balanced shadow. 3. The absence of stars is a problem with film exposure. If you want to capture stars, everything on the moon will be overexposed.

There is no shadow because John Young is not standing on the ground, but jumping up, in semi-"real" air, so the shadow is several feet away from his body. 4. Looking closely with a microscope, the letter C is just the shadow of a hair or clothing fiber on the photographic paper.

5. That reflection is some permanent glass on the lunar horizon.

5. Little knowledge about aerospace technology

1. The characteristics of electronic equipment on aerospace vehicles are: ① Small size, light weight and low power consumption are required; ② Can operate in harsh environments Working conditions; ③ High efficiency, high reliability and long life.

These requirements are particularly stringent on high-performance aircraft and spacecraft. The cabin volume, load capacity and power supply of aircraft and spacecraft are strictly limited.

For every 1 kilogram increase in the weight of the equipment on the satellite, the launch weight of the launch vehicle will increase by several hundred kilograms or more. Missiles and spacecraft must withstand severe impact overloads, strong vibrations, and particle radiation.

Some spacecraft have a very long working time, such as geostationary communication satellites, which last for 7 to 10 years, while deep space probes work for even longer. Therefore, electronic components used in aerospace must undergo extremely strict quality control and screening, and the design of electronic systems requires full use of reliability theory and redundancy technology.

2. The main development directions of aerospace electronics technology are: ① Make full use of electronic computers and large-scale integrated circuits to improve the level of integration, automation and intelligence of aerospace electronic systems; ② Improve real-time signal processing and data processing capabilities and data transmission rates; ③ Develop high-speed and ultra-high-speed large-scale integrated circuits; ④ Develop electronic technology in higher frequency bands (millimeter waves, infrared, optical frequencies); ⑤ Develop higher reliability and various electronic components with longer life.

6. Scientific and technological knowledge about rocket structure

The basic components of a rocket include the propulsion system, rocket body structure and payload.

Controlled rockets are also equipped with guidance and control systems, and sometimes telemetry, safety self-destruction and other additional systems can be installed on the rocket as needed. The propulsion system is the source of power for rocket flight.

The propulsion system of a solid rocket is a solid rocket motor. The propulsion system of a liquid rocket includes an engine, propellant tank, pressurization system and pipeline valve group (see aircraft propulsion system).

The function of the rocket body structure is to load all the components of the rocket to form a whole. Usually the casing of the solid rocket motor and the box of the liquid rocket form part of the rocket body structure.

In addition, it also includes the tail section, interstage section, instrument cabin structure and payload fairing. The rocket body structure should have good aerodynamic shape.

On the premise of completing the same function, the smaller the weight and volume of the rocket body structure, the better. In order to reduce the weight of the rocket body structure, in addition to design skills and process methods, the selection of structural types and materials is also very important.

The payload is the object that the rocket is intended to transport. Rockets serve different purposes and have different payloads.

The payload of a military rocket is the warhead (warhead). The payloads of scientific research rockets are various research instruments.

The payload of the launch vehicle is spacecraft such as artificial satellites, manned and unmanned spacecraft or space probes.

7. Little knowledge about aerospace

Haha, I want to participate in this competition too.

I found it, so.

I won’t tell you! Forget it, let me tell you! 1. Physical health: Carry out high-intensity physical exercise every day, run at least two miles (about 3.2 kilometers), ride a bicycle for 15 minutes, swim in a 50-meter lane for five rounds, and lift weights without interruption for 15 minutes. 2. Teamwork and learn to get along with others.

Space on a spaceship is small, and you have to know how to live with the other crew members. 3. Foreign language proficiency: Understand basic Russian.

But it's not that simple. Mark Shuttleworth, a South African billionaire who spent huge sums of money to carry Russian spaceships for space tourism in 2002, once said that four hours of Russian language classes a day is like brain surgery, which is not enough.

4. Physical examination Good health is required. People with heart disease are absolutely not allowed to go to heaven, but people with mild asthma will not be affected.

5. Psychological examination Mental health is also very important, especially the ability to remain calm no matter what the situation. An astronaut can face all kinds of dangers, and there is no escape in space.

6. Overweight endurance training Overweight endurance training requires astronauts to maintain normal breathing and thinking abilities while withstanding a gravity eight times their own body weight. This kind of training is usually completed in a high-speed rotating centrifuge chamber or a rotating seat. The greatest pressure in training is to withstand acceleration. The training of astronauts requires overloading to an acceleration of 8 times the human body's own weight, lasting 40 to 50 seconds. .

In manned space flight training, overweight endurance training is the biggest challenge to astronauts' self-limits. This is the famous devil training that many people shy away from. 7. First aid training Basic first aid knowledge is common sense to astronauts, such as splinting the leg after a fracture and applying medicine to the wound.

8. Land survival training simulates a space shuttle crashing unexpectedly in the wilds of Russia. Trainees must receive basic survival training such as how to make a fire, how to build a temporary shelter, and how to call for help. 9. Sea survival training In the event of an accident, astronauts should also be prepared to make an emergency landing in the Black Sea.

One of the trainings is for astronauts to jump into the water wearing spacesuits and learn to inflate the lifeboats themselves in the water. 10. Weightless training In a weightless state, all daily tasks such as eating, drinking, going to the toilet, vomiting, etc. need to be relearned, otherwise it may cause a lot of trouble for you and others.

NASA's medical experts have specially developed a large instrument called the "vomit comet machine". As long as astronauts "live" in this instrument for 100 hours before going into space, then, After he goes to space, he will no longer vomit. In this constantly rotating machine, astronauts have to learn to put on their space suits within 30 seconds.

11. Learn to fly a space shuttle. Any accident can happen during space travel. Therefore, if the automatic control system fails and causes an accident, or all other crew members are killed, someone must be able to drive the space shuttle back to Earth. 12. Money Last but not least, you should have at least $20 million.

1. On November 24, 2007, my country’s first lunar exploration satellite was successfully launched. The name of this satellite is Chang’e-1. 2. On November 24, 2007, the launch vehicle carrying my country's first lunar exploration satellite was ignited and launched from the Xichang Launch Center.

3. At present, there are three satellite launch bases in our country, and the fourth launch base is about to be built in Wenchang and is expected to be put into use in 2010. 4. On April 14, 2007, my country successfully launched a Beidou satellite into space using the "Chang Sanjia" carrier rocket. This satellite is a satellite in my country's "Beidou Project". The main purpose of the "Beidou Project" is positioning and navigation. .

5 To commemorate Galileo’s first observation of the starry sky with a telescope 400 years ago, in March 2007, the International Astronomical Union (IAU) designated 2009 as the International Year of Astronomy, with the theme: “The Universe – yours to discover”. 6. The following statement about planets is wrong. Jupiter was called ‘Chang Geng’ in ancient my country. It is the most massive of all the planets in the solar system.

7. So far, humans have launched a large number of probes to examine other planets in the solar system. The correct correspondence between the following probes and the detected planets is Galileo and Jupiter 8. The following is about the mass of the solar system. The top five largest planets, in descending order of mass, are Jupiter, Saturn, Neptune, Uranus, and Earth. 9. The Messier number of the Orion Nebula is M4210. The following descriptions of the meanings of each solar term are incorrect. On the day of the winter solstice, the sun's declination is 0 degrees, and the sun shines almost directly on the Tropic of Capricorn. It is the shortest day of the year in the northern hemisphere. 11. Human beings have named many places on the moon. The following names that do not belong to the moon are Olympus Mons. 12. Most of the craters on the moon are named after astronomers, including ancient Chinese astronomers. The following The person whose name is not used is Song Yingxing. 13. The correct statement about telescopes is that compared with horizontal telescopes, the advantage of equatorial telescopes is that they are easier to track the diurnal movements of celestial bodies. 14. The orbital plane of the moon around the earth The angle between it and the lunar equator is 6 degrees 41 minutes, which allows us to see some of the far side of the moon from the Earth's north and south poles.

15. The following statement about comets is incorrect because comets are heated when they are close to the sun, and the light of comets is mainly emitted by hot gas. 16. The discovery of asteroids is closely related to the proposal of the Titius-Bode rule. According to this rule, there should be a planet at a distance of 2.8 astronomical units from the sun. Piaget subsequently discovered it there. The first asteroid Ceres 17. There are planets in the solar system that radiate more energy than the solar radiation they receive. So far, such planets are known to include Jupiter and Saturn. 18. The planets outside Saturn There is a dark gap in the middle of the ring that divides the ring into two parts, the inner and outer parts. This gap is named after its discoverer and is called the Cassini ring gap 19. We can roughly know by observing the moon phases The date of the day in the month, such as when the moon phase is first quarter, is probably around 20 on the eighth day of the lunar calendar of each month. Among the eight planets in the solar system, there is a planet with a very unique way of rotation. Its equatorial plane and revolution The angle between the orbital planes is 97 degrees and 55 minutes. It almost rotates on the orbital plane. Which planet is this? Uranus 21. Which of the following celestial bodies.