March variants to steer stages during re-entry. However, Long March 5B has yet to demonstrate these capabilities. The debris found at Ivory Coast in May Long March 5 (LM-5; Chinese: 长征五号; pinyin: Chángzhēng wǔ hào) or Changzheng 5 (CZ-5), also known by its nickname "Pang-Wu" (胖五, "Fat-Five"), is a Chinese heavy-lift launch vehicle developed by the China Academy of Launch Vehicle Technology (CALT). The most powerful Chinese rocket and Long March rocket ever built, it is also the most powerful orbital launch vehicle operating outside of the United S The first stage of the Long March 5B variant, which can reach orbital velocity and weighs 21.6 tonnes, currently lacks the capability for controlled atmospheric re-entry, meaning that debris could cause damage on the ground upon re-entry. Without modification, it is expected all LEO launches of the Long March 5B will result in uncontrolled re-entries. The 5B is the specific variant in concern due to its unique LEO configuration. The core rocket stage (first stage) is launched directly into orbit, which also unusually serves as the upper stage to perform payload insertion. Typically, the rocket's first stage never reaches orbital velocity, while the smaller upper stage will usually burn up in the atmosphere during re-entry. However, Long March 5B's first and upper stage is combined into one, making the mitigation effort more difficult. Potential solutions include restarting engines during re-entry to reduce speed and collision probability, as the case for Long March 2D. China has also developed grid fins on other Long March variants to steer stages during re-entry. However, Long March 5B has yet to demonstrate these capabilities. The debris found at Ivory Coast in May 2022 was reportedly the remains of the first Long March 5B launch (5B-Y1). Although the probability of rocket debris hitting populated areas is mathematically minuscule, some scientists fear the lax attitude of many countries could eventually result in casualties. Responding to the criticism, CNSA claimed they had conducted measures to ensure safe re-entries. Xu Yansong, former director for international cooperation at the China National Space Administration (CNSA), told the audience on the CNSA live stream for 5B-Y3 that the re-entry process was improved with the "passivation process" (Chinese: 钝化处理), and the core stage was specially designed with lighter materials so the vast majority of components will be ablated during the re-entry. Before the launch of 5B-Y4, Liu Bing, deputy director-designer of the Long March 5B, told journalists that "an elaborative evaluation" was performed on the 5B to enable safe re-entry, though no details regarding the improved re-entry procedure were revealed. The…