China Sends Stem‑Cell Embryo Models to Tiangong Station

China has launched the world's first experiment involving artificial human embryos into space, aiming to study the effects of the space environment on early human development. The embryolike structures, derived from human stem cells, arrived at the country's Tiangong space station on May 11 aboard the Tianzhou-10 cargo spacecraft.

The project is led by researchers from the Chinese Academy of Sciences. According to project leader Yu Leqian, the structures are not real human embryos and cannot develop into an individual. Instead, they serve as a model for studying the earliest stages of development, which are difficult to research using actual human embryos due to international ethical guidelines.

Two types of models were sent into orbit. One replicates the stage when an embryo attaches to the uterine wall. The other represents a phase between approximately 14 and 21 days after fertilization, when cells reorganize into distinct layers that will eventually form tissues and organs. This period is considered crucial for proper fetal development.

The experiment was designed to last for five days. An automated system on the space station provided daily care to the samples, which were...