The Structure and Technology of China's First Star

On April 24, 1970, China's first satellite, Dongfanghong-1, was successfully launched into the sky by the Long March 1 carrier rocket under the attention of the public, ushering in a new era of China's space exploration. The diameter of Dongfanghong-1 is only one meter. Engineers designed it as a quasi spherical shape with seventy-two faces, so that its trajectory cross-section changes little at any attitude during space operation. Without the need for on-board instruments, the atmospheric density and its changes in the operating area can be calculated from orbit data; It has four three meter long "antennae" on its body, which are its antennas. The music device used for singing emits radio waves through the antenna, completing communication between satellites and the ground, and can also play "Eastern Red Music" to people all over the world. Hand cranked computers and slide rules were early calculation tools based on mechanical and logarithmic principles. Hand cranked computers achieve basic arithmetic through mechanical transmission, while slide rules simplify multiplication and division operations using logarithms. Both were popular before the popularization of electronic devices.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

Hand cranked computers and slide rules are tools based on mechanical principles and logarithmic concepts to perform computational tasks. Hand cranked computers convert user inputs (such as rotating handles) into numerical increases or decreases through a mechanical transmission system of gears and shafts, thereby achieving basic arithmetic operations. The slide rule utilizes the concepts of logarithms and exponents to simplify complex mathematical operations, especially multiplication and division, through a series of scales and sliders. Users can directly read the calculation results by moving the slide ruler and aligning it with the scale on the fixed ruler, without the need for tedious pen calculations. These two tools provided important computational support for scientific research and engineering calculations before the emergence of electronic calculators and computers. Hand cranked computers and slide rules have milestone significance in the history of China's technological progress, witnessing the historical process of China's transition from technological backwardness to gradually catching up and achieving significant technological breakthroughs. Through the application of these tools, China has not only become.