South Korea has successfully tested a solid-propellant spacecraft. This was reported on Friday, December 30, by the largest news agency of the republic, Yonhap.
Eyewitnesses observed the rainbow tail of an unidentified flying object in the sky, but no explosions were heard. South Korean media, citing the military, have already reported that the republic has successfully tested a solid-propellant launch vehicle. And the color effect could appear in less dense layers of the atmosphere due to the freezing of rocket fuel particles.
A solid rocket is a rocket with an engine that uses solid fuel and an oxidizer as fuel. The advantages of such aircraft are relative simplicity, the absence of the problem of possible leaks of toxic fuel, low fire hazard, the possibility of long-term storage, and reliability in operation. Such rockets were rarely used in Soviet and Russian cosmonautics, but they are widely used in rocket technology in other countries, for example, in the United States. Basically, these are elements of the first stage (side boosters).