Engineering topics

Dardano, C. B.

Publications and source records attributed to Dardano, C. B..

3 records

NASA NTRS1994

LDEF meteoroid and debris database

The Long Duration Exposure Facility (LDEF) Meteoroid and Debris Special Investigation Group (M&D SIG) database is maintained at the Johnson Space Center (JSC), Houston, Texas, and consists of five data tables containing information about individual features, digitized images of selected features, and LDEF hardware (i.e., approximately 950 samples) archived at JSC. About 4000 penetrations (greater than 300 micron in diameter) and craters (greater than 500 micron in diameter) were identified and photodocumented during the disassembly of LDEF at the Kennedy Space Center (KSC), while an additional 4500 or so have subsequently been characterized at JSC. The database also contains some data that have been submitted by various PI's, yet the amount of such data is extremely limited in its extent, and investigators are encouraged to submit any and all M&D-type data to JSC for inclusion within the M&D database. Digitized stereo-image pairs are available for approximately 4500 features through the database.

Dardano, C. B.↗

NASA NTRS1989

The detection and observation of meteoroid and space debris impact features on the Solar Max satellite

The results of optical observations on the entire population of impact pits and holes discovered on nearly all of the returned parts of the Solar Maximum Mission satellite are described. Some statistically significant new results on impact dynamics are obtained as well as new number vs. size distributions for craters and holes ranging from 40 to 900 microns. The local spacecraft geometric shielding corrections are calculated and applied to the data. Some selected compositional results are presented which indicate that the Space Shuttle can be a source of impacting debris.

Warren, J. L.↗

NASA NTRS1988

How successful were the lunar sampling tools: Implications for sampling Mars

Like the Mars Sample Return endeavor, the Apollo lunar-sample program began with definition of strategy for sample collection and of scientific requirements for sampling hardware design. Several lessons can be illustrated by specific tools. The evolution of drive tubes from narrow 2 cm diameter, thick-walled tubes (used on Apollo 11, 12 and 14) to 4 cm diameter, thin-walled tubes used on Apollo 15, 16, and 17) as an example of the improvements made possible during multiple missions. The original Apollo 11 drive tube was designed to work in fluffy soil; thus, only 50 percent of the relatively dense lunar soil was recovered, and the core was distorted. The final configuration resulted in nearly 100 pct recovery with little distortion. The surface samplers (Contact Soil Sampling Devices) were designed to collect the upper 100 micrometer or the upper 1 mm of soil. It was over 2 years after the mission before these particularly specific samplers were opened because interest in them waned. Both core tubes and surface samplers were difficult to open in the laboratory. The Apollo Lunar Sample Return Containers (ALSRCs) were constructed with one indium and 2 Viton seals. They were closed on the lunar surface. Interior container pressures measured upon return to the laboratory indicate that these seals were not reliable in the lunar environment. Also, choice of indium as a sealing material interfered with siderophile analyses of samples.

Allton, J. H.↗