Luna Research Dome 4 — biomedical and radiosynthesis research campus at Mare Frigoris, on the same crater complex as Dome 3. Operational since 2109. Originally split off from Dome 2’s biological monitoring work. Houses the hematology and radiobiology division under Dr. Klaus Jäger, developer of the MHA-1 melanized hemoprotein (“black blood”) treatment derived from Dominium Hominis tissue samples. Also associated with Dr. Ian Johnson and Dr. Liang Qiuyue in later eras for Johnson Drive derivation work.