Korea’s first satellite, Woori Byul No. 1 (Source: KAIST Satellite Research Institute)It has achieved great success after repeated failures. Korea has become the 11th member of the Space Club, which includes advanced countries such as the U.S., Russia, and other countries. Satellite OrbitSputnik 1, the world’s first satellite (Source: NSSDC/NASA)Korea’s First Satellite Korea’s first satellite is the first Korean star developed by the Korea Advanced Institute of Science and Technology (KAIST) Satellite Research Center and was launched on August 11, 1992 (see figure).The radius of a satellite’s orbit can be compared in the figure. Radius of bit is shown on the left side of the horizontal axis, and Height above sea level is shown on the right side of the horizontal axis. Low Earth Orbit: It is an orbit between 200 and 2000 km above the ground, located between the Earth’s atmosphere and the Van Allen belt, and is in this orbit with the Hubble, International Space Station, and so on. It is located in the inner orbit of Earth and thus has a short orbital period. For example, the International Space Station’s orbital period is about 93 minutes. Geostational Earth Orbit: It is an orbit from 20,000 km above the ground to Earth’s normal orbit, and the GPS satellite’s orbit is located 20,000 km above the ground. Geostational Earth Orbit: It is located 35,800 km above the ground and is also called a geostationary orbit. The orbital period is the same as the Earth’s rotation period for 24 hours. This corresponds to the case where the orbital period of an object orbiting this orbit coincides with the rotation period of a planet or moon. In general, communication satellites or weather satellites orbit around Earth.High-Earth Orbit: Orbit outside Earth’s normal orbit, satellites generally travel in elliptical orbit. Gamma-ray and X-ray observation satellites such as the Vela satellite and the Newton telescope (XMM-Newton) are located in this orbit. The number of satellites in Korea is about 10. Korea’s first star, No. 1 star, No. 2 star, No. 3 science satellite, No. 1 Naro science satellite, No. 1 Arirang, No. 2 Arirang, No. 3 Korea’s second star was developed purely in Korea based on No. 1 by KAIST professor Choi Soon-dal and participation by foreign companies. The Korean company’s participatory Naro science satellite was developed based on No. 1 and No. 2 by domestic companies. It was built to check the orbit of satellites and explore the environment of outer space once every 103 minutes at an altitude of 300 kilometers and 1,500 kilometers at a distance. It measures the radiation of space ions in space. Arirang 1 is used for marine resources and marine observation on the Korean Peninsula, Arirang 3 is used for monitoring volcanic eruptions, weather observation, and Korea is the seventh country in the world to have a weather observation satellite. In June 2022, Korea’s independently developed projectile, Nuri-launched ~^The interactive communication between the performance verification satellite and the ground station was successfully carried out on the early morning of the 22nd.As the successful launch of the Nuri spacecraft, the satellite’s orbital settlement, and the normal operation of the satellite are confirmed through two-way communication, Korea is fully equipped with the capacity to launch a practical satellite. The Ministry of Science and ICT and the Korea Aerospace Research Institute (KARI) successfully communicated with the Daejeon Korea Aerospace Research Institute at 3:01 a.m. on the 22nd. Accordingly, for the first time in Korea, it succeeded in communicating by launching a satellite developed on its own without borrowing foreign projectiles and confirming that the satellite is operating normally.Our star’s number 1 on boardA satellite is a man-made satellite, that is, an artificial device launched by using a rocket so as to revolve around a planet such as the Earth. Among the celestial bodies that make up the solar system, a natural celestial body that orbits by the attraction of a planet is called a satellite. A satellite is a satellite that is artificially made by humans to achieve a certain purpose and placed around the Earth mainly. It can be divided into geostationary orbit satellites and non-terrestrial orbit satellites according to the purpose and use, and is classified into science satellites, communication satellites, military satellites, and weather satellites according to the purpose. The principle of artificial satellites can be explained by the shape of the trajectory formed by shells fired in a horizontal direction parallel to the ground. If the speed of the shell being fired starts at 1 kilometer per second and gradually increases, the distance the shell flies will gradually increase, and theoretically, if the speed of the shell reaches 7.9 kilometers per second, it will not fall back to the ground and will continue to revolve around the Earth. And if the speed of the shell exceeds 11.2 kilometers per second, it will escape the Earth’s gravitational sphere. In the end, satellites with speeds of 7.9 kilometers per second or more and 11.2 kilometers per second or less will revolve around the Earth due to gravity. At this time, if the flying speed is 7.9 km per second, it becomes a circular orbit, and if the flying speed is higher than that, it becomes an elliptical orbit centered on the Earth. <History of Satellites> The idea that if an object floating in space can maintain a constant speed, it will be able to orbit the Earth forever without falling to the ground has been well known since the Newtonian era. However, no way to achieve such a high speed has been developed. In fact, the V2 rocket that Germany used in World War II started the launch of a satellite capable of flying. After the end of the World War, the Soviet Union (Soviet Union, now Russia) that was in the midst of the Cold War with the United States developed an improved V2 rocket engine, and succeeded in launching the world’s first satellite using it. Soon after, the Soviet Union attempted the possibility of life’s space flight by boarding a dog named ‘Laika’ on its second satellite. The world’s first satellite, built by mankind, is Sputnik 1, developed by the Soviet Union (formerly Soviet Union), and was launched on October 14, 1957.KSLV-1, which was launched from the Naro Space Center in 2009, is truly the beginning of our space development. The KSLV-2 that will be launched in 2009 is 1.5 tons, larger than the Mugunghwa satellite, and will be able to develop and use various satellites, including communication satellites. Although it failed to get into orbit, it was a great development just by launching a satellite from our land with a rocket made with our technology. The Naro Space Center challenged the third launch at 4 p.m. on January 30, 2013, taking advantage of two failed attempts. With the whole nation and the world watching, the Naro flew into the sky. The Naro dropped the first engine into the sea in 232 seconds, ignited the second engine in 395 seconds, and separated the Naro Science Satellite in 540 seconds.Comparison of orbital radii of other satellites such as normal orbit around Earth and GPSThe launch of Korea’s first space launch vehicle, Naro
