Planetary quarantine in the solar system. Survival rates of some terrestrial organisms under simulated space conditions by proton irradiation.
We have been studying the survival rates of some species of terrestrial unicellular and multicellular organism (viruses, bacteria, yeasts, fungi, algae, etc.) under simulated interstellar conditions, in connection with planetary quarantine. The interstellar environment in the solar system has been simulated by low temperature, high vacuum (77 K, 4 x 10(-8) torr), and proton irradiation from a Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years of irradiation in solar space, tobacco mosaic virus, Bacillus subtilis spores, Staphylococcus aureus, Micrococcus flavus, Aspergillus niger spores, and Clostridium mangenoti spores showed survival rates of 82, 45, 74, 13, 28, and 25%, respectively.
Koike
J
J
Department of Life Science, Tokyo Institute of Technology, Yokohama, Japan.
Oshima
T
T
D001419:Bacteria / Q000528:radiation effects; D003264:Containment of Biohazards; D004783:Environmental Microbiology; D056890:Eukaryota / Q000528:radiation effects; D005118:Extraterrestrial Environment; D005658:Fungi / Q000528:radiation effects; D018535:Mars; D011522:Protons; D011836:Radiation Tolerance; D016082:Solar System; D018561:Space Simulation; D013171:Spores, Bacterial / Q000528:radiation effects; D013172:Spores, Fungal / Q000528:radiation effects; D013242:Sterilization; D013696:Temperature; D014618:Vacuum; D015003:Yeasts / Q000528:radiation effects
D011522:Protons