Viking Pre-Sterilization

Viking Post-Sterilization

Other Approaches

Mars Pathfinder Lander/ Rover

No LifeDetection Instruments

COSPAR Category IVa


Assembly was done in class-100,000 clean rooms. All exposed surfaces were cleaned by alcohol wiping or dry heat, except that Sojourner rover was precision cleaned by Freon vapor degassing. Pre- and post-process microbial burden tests were performed for components that had not maintained humidity controls during heating. During early assembly, test, and launch operations at JPL, flight hardware was periodically cleaned by alcohol wiping. Final aerobic spore density and total burden were calculated at 14.9 spores m–2 and 2.9 × 10 4 spores, respectively.c


At Kennedy Space Center, SAEF-2 clean-room and strict personnel garment requirements were used; ground-support equipment and nonflight equipment were alcohol wiped.

Beagle 2 Lander/ Rover

Life-Detection Instruments

COSPAR Category IVa+


The probe was assembled aseptically in a class-100 clean room. Some components were sterilized with dry heat. Gamma irradiation, gas plasma, and alcohol wipes were used to sterilize technologies that were susceptible to heat. The assembly facilities were monitored at Viking levels for microbial presence, and assays were conducted based on NASA protocols.d

The completed probe was sealed in a front and back shield and bioseal and protected from recontamination by a HEPA filter. The probe was fitted with the Mars Express spacecraft in Toulouse, France, at a class-100,000 clean room and assembled and integrated with the launch vehicle in Baikonaur, also in a class-100,000 clean room. The external area of the Beagle was cleaned at each location.d

Established policies and procedures for planetary protection were followed in the assembly facility, including training, apparel, monitoring of people and material flow into assembly area, cleaning, cleaning of hardware, and sterilization.

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