China's commercial rocket firm LandSpace successfully conducted a crucial ground ignition test of the first-stage propulsion system for its reusable Zhuque-3 rocket on Friday.
This significant milestone propels the rocket toward the project's planned 2025 debut flight.
Conducted at the Dongfeng commercial space innovation pilot zone near the Jiuquan Satellite Launch Center in northwest China, the test featured China's largest and most automated nine-engine parallel cluster hot-fire test to date, announced LandSpace.
The test utilized a first-stage structure that is consistent with the technical status of the Zhuque-3's maiden flight mission, said the Beijing-based rocket firm.
"This test achieved an exceptionally high degree of fidelity to actual flight conditions and replicated exactly how the system will fly in space during the test on the ground," said a press release of LandSpace.
The comprehensive trial rigorously simulated the entire pre-launch and flight sequence, covering propellant loading, tank pressurization, sequential engine ignition in batches, sustained stable operation and programmed shutdown procedures, according to the press release.
The 45-second test is powered by nine of LandSpace's self-developed liquid oxygen-methane engines, which generated a total thrust of 7,542 kilonewtons (kN).
It validated the compatibility between all major subsystems -- engines, pressurization and delivery systems, structures and avionics -- and verified the rational design of the ground support and launch control processes, LandSpace said.
"After the 40-second ignition test of our Zhuque-3's first-stage power system, we have fully verified the rationality of the design and the working compatibility of the rocket's subsystems of avionics, structure, engines, and power. At the same time, it also verified the coordination and rationality of entire rocket-ground testing procedure," said Dai Zheng, commander in chief of Zhuque-3 reusable rocket.
The Zhuque-3 rocket has a diameter of 4.5 meters and a total length of around 66 meters, with its first stage designed to be reused at least 20 times. It can launch multiple satellites at one time, such as flat stackable satellites.
Its storage tank is made of high-strength stainless steel, and it has the potential to reduce launch costs by 80 to 90 percent compared to single-use rockets.
The first-stage engine of Zhuque-3 can be checked without being separated from the rocket after it is recovered, and can fly again after refueling, much like plane flights, according to LandSpace.
China's reusable rocket Zhuque-3 completes major engine cluster test
A video featuring a former member of Unit 731, a notorious Japanese germ-warfare unit during World War II (WWII), was released on Thursday in northeast China's Harbin, revealing details of how the unit used meteorological data to conduct horrific bacterial experiments on human beings.
The video was released by the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in which former Unit 731 member Tsuruo Nishijima detailed how the unit used meteorological data to carry out a bacterial dispersal experiment.
The video was recorded in 1997 by Japanese scholar Fuyuko Nishisato and donated to the exhibition hall in 2019, according to the hall, which was built on the former site of the headquarters of Unit 731 in Harbin, the capital city of Heilongjiang Province.
Jin Shicheng, director of the Department of Publicity, Education and Exhibition of the exhibition hall, said that Nishijima joined Unit 731 in October 1938 and served in the unit's meteorological squad. The squad was not a simple observation section but rather an auxiliary force supporting the unit's field human experiments by measuring wind direction, wind speed, and other conditions to ensure optimal experimental results, according to Jin.
Nishijima confirmed in the footage that "the meteorological squad had to be present at every field experiment." He testified to the "rainfall experiments" conducted by Unit 731, which involved aircraft releasing bacterial agents at extremely low altitudes.
At a field-testing site in Anda City, Heilongjiang, Unit 731 aircraft descended to about 50 meters above the ground. They sprayed bacterial culture liquids onto "maruta" -- human test subjects -- who were tied to wooden stakes. Each experiment involved about 30 people, spaced roughly 5 meters apart. After the experiments, the victims were loaded into sealed trucks and transported back to the unit, where their symptoms and disease progression were recorded over a period of several days.
"Unit 731's bacterial weapons were dropped by aircraft from a height of 50 meters in the open air. Therefore, the meteorological squad needed to observe wind direction and speed, which directly affected the precision and accuracy of the bacterial weapons deployment," said Jin.
Nishijima recounted the harrowing experience of the human test subjects.
"They were fully aware that inhaling the substances would certainly lead to death, so they closed their eyes and held their breath to avoid breathing them in. Their resistance prevented the experiment from proceeding. To compel them to comply, they were forced at gunpoint to open their mouths and lift their heads," said Nishijima.
These experiments, disguised as "scientific research," were in fact systematic tests of biological warfare weapons conducted by the Japanese military. The data generated from these inhumane activities became "research findings" shared among the Japanese army medical school, the medical community, and the military at large.
"At that time, the entire Japanese medical community tacitly approved, encouraged, and even participated in the criminal acts of Unit 731. The unit comprised members from Japan's medical and academic sectors who served the Japanese war of aggression against China. Thus, Unit 731 was not just a military unit but represented an organized and systematic criminal enterprise operating from the top down," said Jin.
Unit 731 was a top-secret biological and chemical warfare research base established in Harbin as the nerve center for Japanese biological warfare in China and Southeast Asia during WWII.
At least 3,000 people were used for human experiments by Unit 731, and Japan's biological weapons killed more than 300,000 people in China.
Video offers details of Japan's germ-warfare crimes in northeast China
