Engineering Papers⌕ Search

Engineering topics

Albee, A. L.

Publications and source records attributed to Albee, A. L..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Comet coma sample return via Giotto II

A comet coma sample return is possible with a low-cost flyby mission. Collecting coma materials and returning them to earth can be accomplished in a free-return trajectory. Intact capture of coma dust, preserving the cometary dust mineralogy, is possible at low encounter speeds. Samples from a known cometary source can then be compared with the wealth of information on meteorites and interplanetary dust. Sample return via Giotto II is a unique, low-cost NASA/ESA cooperative opportunity. With ESA providing the Giotto spacecraft and payload and NASA the sample return capability, first-class science can be accomplished at a very low cost for both NASA and ESA. This paper focuses on the sample return aspects, including sample return objectives, sample collection techniques, experimental work to verify collection concepts, and some of the characteristics of the cometary targets for sample return.

Tsou, P.↗
NASA NTRS1984

Mars exploration in the 1990's

Science objectives for a Mars exploration program in the 1990s, set forth by NASA's Committee on Planetary Exploration, are presented. They include: an intensive study of the Martian surface, the exploration of the structure and general circulation of the atmosphere, the exploration of the nature and dynamics of the planet's interior, the nature of Mars's magnetic field, the character of the upper atmosphere and its interaction with the solar wind, and the establishment of the global chemical and physical characteristics of the Martian surface. Several low cost missions, which have been suggested by the Committee for NASA's CORE program, such as the Mars Geoscience Climatology Observer, the Mars Aeronomy Orbiter, and the Mars Surface Network and Surface Probing missions are also covered. Direct Entry-Direct Return and Out-of-Orbit Entry-Orbital Rendezvous and Docking are two versions of a Mars Rover and Sample Return (MRSR) mission discussed in detail. It is concluded that a MRSR mission will require the combination of full Centaur capability, aerocapture at Mars and earth, and direct return to earth to meet major scientific goals. Further studies should be made in orbit assembly, fuel transfer technology, aeromaneuvering, terminal guidance, rover technology, and robotics.

Albee, A. L.↗
NASA NTRS1984

Quantitative use of multiincidence-angle SAR for geologic mapping

It is proposed that techniques be developed and used for quantitative interpretation of shuttle imaging radar-B (SIR-B) data for lithologic identification and mapping. The use of backscatter versus incidence angle signatures derived from SIR-B images is to be investigated. The use of SIR-B with other sensors for geologic mapping is also to be considered. Anticipated results are discussed in terms of geologic mapping.

Farr, T. G.↗
NASA NTRS1983

Development of a miniature scanning electron microscope for in-flight analysis of comet dust

A description is presented of an instrument which was developed with the original goal of being flown on the International Comet Mission, scheduled for a 1985 launch. The Scanning Electron Microscope and Particle Analyzer (SEMPA) electron miniprobe is a miniaturized electrostatically focused electron microscope and energy dispersive X-ray analyzer for in-flight analysis of comet dust particles. It was designed to be flown on board a comet rendezvous spacecraft. Other potential applications are related to asteroid rendezvous and planetary lander missions. According to the development objectives, SEMPA miniprobe is to have the capability for imaging and elemental analysis of particles in the size range of 0.25 microns and larger.

Conley, J. M.↗
NASA NTRS1982

Petrology and petrogenesis of lunar breccia 12013

Sample 12013 is extremely rich in incompatible elements (K, P, U, Th, Pb, Ba, Rb, Zr, Nb, and rare earths) relative to other lunar samples, and it contains abundant granitic material composed of silica minerals and K-feldspar. The present investigation provides detailed petrologic and mineralogic descriptions of the rock and a discussion of its genesis and history. The sample is made up of two lithologies, including a mottled gray and white lithology, and a black lithology. A detailed petrology of the gray breccia is presented, taking into account lithic clasts, mineral clasts, deformation textures in clasts, the matrix, and felsite. A detailed petrology of the black breccia is also provided. Attention is given to a model for the formation of the breccia, an evaluation of the possible genetic relationships between the various components, and some constraints on the nature of the source area.

Quick, J. E.↗
NASA NTRS1980

The geology and petrology of the Apollo 11 landing site

Geochemical and petrologic data indicate that the 73 Apollo 11 basalts thus far identified can be divided into five petrologic groups (A, B1, B2, B3, D) which must represent at least five separate igneous cooling units. These five igneous bodies range in age from 3.90 b.y. to 3.60 b.y. Photogeologic studies indicate that three mare units are present, and that the lunar module set down on the oldest of the three. The exposure age data suggest that the high-K flow is the surficial rock type at the landing area, and is, therefore, probably the oldest of the three mare units. By examining the size frequency distribution and the inferred cooling rates of the individual samples, it is possible to calculate the formation thicknesses within the 30-m-deep West Crater. This suggests that A = 9 m, B1 = 2 m (and may be an ejecta blanket), B2 is equal to or greater than 8 m, and B3 = 6 m.

Beaty, D. W.↗
NASA NTRS1979

The petrology and chemistry of basaltic fragments from the Apollo 11 soil - I

A study of basaltic fragments from the Apollo 11 bulk sample using instrumental neutron activation analysis, the petrographic microscope, and the electron microprobe is presented. The fragments include Group A, B2, and B3 basalts, of which two of the Group A samples are vitrophyres with bulk compositions similar to the crystalline high-K rocks which crystallized under different physical conditions and represent a second high-K cooling unit. The B2 samples relate to each other through ilmenite fractionation, and the B3 samples relate through olivine fractionation; it is concluded that the B2 samples have an anomalously high La/K ratio and may have generated in the same source region as the Group D basalts.

Beaty, D. W.↗
NASA NTRS1979

Apollo 12 feldspathic basalts 12031, 12038 and 12072 - Petrology, comparison and interpretations

The paper presents the petrology of Apollo 12 feldspathic basalts. Modal and chemical data indicate that basalts 12072, 12038, and 12031 cannot be related to the other Apollo rock types; 12072 contains phenocrysts of olivine and pigeonite, 12038 is a multiply saturated equigranular basalt, and 12031 is a coarse-grained rock with granular to graphic intergrowths of pyroxene and plagioclase. The bulk compositions indicate that these basalts could not have been derived from the Apollo 12 olivine or ilmenite basalts by crystal-liquid fractionation, and their petrologic similarities suggest that they were produced in the same or similar source regions.

Beaty, D. W.↗
NASA NTRS1979

The petrology of the Apollo 12 pigeonite basalt suite

A study of the petrology of the Apollo 12 pigeonite basalt samples 12011, 12043, and 12007 is presented. In this suite, the abundances of olivine and Cr-spinel decrease with increasing grain size, while the abundances of plagioclase and ilmenite increase. The petrochemical and textural variations indicate that the pigeonite basalts were derived from the olivine basalts, but the compositional gap between the olivine and pigeonite basalts indicates that they could not have crystallized together from a single, initially homogeneous magma body.

Baldridge, W. S.↗
NASA NTRS1978

Petrology, chemistry, age and irradiation history of Luna 24 samples

The results of petrological, chemical, isotopic age determination and irradiation studies of sample 24170 from the 170 cm depth of the regolith core returned from Mare Crisium by Luna 24 are presented. The sample is found to be comprised of fragments from a single igneous rock, with mineralogical evidence indicating it to be a mare basalt. The crystallization age is determined by Sm-Nd and Ar(40)-Ar(39) ages to be 3.30 AE, establishing the presence of relatively young flows. All soil samples show low trace element compositions with minimum contamination by KREEPUTh-rich materials. Rb-Sr and Sm-Nd relations reflect the absence of significant fractionation at ages younger than 4.5 AE. One soil sample shows extremely large neutron capture effects, imposing a new lower limit to the neutron production rate in the regolith and requiring the addition of irradiated materials from depth.

Wasserburg, G. J.↗
NASA NTRS1978

Comparative petrology and possible genetic relations among the Apollo 11 basalts

A comparative petrological study has been performed on 19 large Apollo-11 basalt fragments as well as two smaller vitrophyres in order to determine how many igneous bodies are presented by this suite of rocks. Detailed petrographic and mineral chemical studies have been performed on each sample along with an electron microprobe point count, which gives the mode, the range and distribution of all mineral zonation and the bulk composition. These data confirm the twofold division of the Apollo-11 basalts into high-K (type A) and low-K (type B) basalts.

Beaty, D. W.↗
NASA NTRS1978

Petrology of Apollo 16 breccia 66075

66075 is a coherent, light matrix breccia with a seriate fabric and is composed of large lithic, mineral and glass clasts in a matrix of lithic, mineral and glass fragments. The lithic clasts are ANT-suite rocks and a texturally diverse suite of impact-generated melt-rocks. The mineral fragments in the matrix and the mineral clasts are mostly plagioclase with subordinate amounts of pyroxene and olivine. The mineral compositions and/or bulk compositions of most of the components of the breccia, as well as the U-Pb isotopic systematics, are compatible with an origin involving impact-melting and fragmentation of an ANT-suite protolith. The major element composition of the breccia matrix can be successfully modeled in terms of mixing the observed clast types. Previously suggested components such as 'dunite' and 'KREEP' are absent or occur in very low abundance.

Quick, J. E.↗
NASA NTRS1977

Report of the Terrestrial Bodies Science Working Group. Volume 2: Mercury

The objectives and rationale for scientific investigation of Mercury are explored. Knowledge already obtained by astronomical observations and Mariner 10 spacecraft is reviewed and measurements required for the principal scientific goals are described. The use of low thrust propulsion systems is recommended so that maximum scientific return may be achieved and the reconnaissance phase of Mercury exploration may be completed in a single mission. Accelerated development is recommended on solar electric propulsion, solar sails, passive and active cooling mechanisms, and single rough landers.

Albee, A. L.↗
NASA NTRS1977

Report of the Terrestrial Bodies Science Working Group. Volume 5: Mars

Present knowledge of the global properties and surface characteraretics of Mars and the composition and dynamics of its atmosphere are reviewed. The objectives of proposed missions, the exploration strategy, and supporting research and technology required are delineated.

Masursky, H.↗
NASA NTRS1977

Petrogenesis of lunar rocks: Rb-Sr constraints and lack of H2O

Rb and Sr isotopic data and other chemical data indicate major lunar differentiation at about 4.6 AE (AE = 10 to the 9th power years) and very limited subsequent differentiation. The constraints of limited differentiation after 4.6 AE and the apparent lack of H2O on the moon, when applied to the derivation and petrogenesis of lunar samples, suggest the following: (1) soil samples, breccias, metaclastic rocks, and feldspathic basalts represent mixtures of repeatedly modified clastic material, which was utimately derived from materials formed during the 4.6 AE differentiation; and (2) mare basalts crystallized from melts which formed by partial melting, and which developed without equilibrium between the melt and crystalline residuum.

Albee, A. L.↗
NASA NTRS1977

Chemical compositions and possible immiscibility of two silicate melts in 12013

The lunar sample 12013, a complex mixture of gray breccia and black breccia, is described. The gray breccia consists of mostly basaltic and gabbroic lithic clasts as well as plagioclase and pyroxene mineral clasts set in a matrix of smaller clasts and a felsite of granitic composition, while the black breccia is comprised of mostly mineral clasts, some lithic clasts, and felsite blebs enclosed in an aphanitic groundmass of basaltic composition. Textural relationships indicate that the felsite and the black breccia groundmass crystallized from melts which coexisted prior to the final lithification of 12013 but failed to mix. Both the felsite and the black breccia groundmass have extreme enrichments of incompatible elements. The critical feature of their compositions is a 'splitting up' of incompatible element associations so that the highest REE and P concentrations are in the black breccia groundmass, and the highest K, Ba, and Rb concentrations are in the felsite.

Quick, J. E.↗
NASA NTRS1976

Petrography of isotopically-dated clasts in the Kapoeta howardite and petrologic constraints on the evolution of its parent body

Results are presented for petrographic and electron microprobe studies of the isotopically dated A, B, C, and rho basaltic rock fragments separated from the howardite Kapoeta. Other lithic clasts and numerous mineral fragments in thin sections of Kapoeta are investigated in order to outline the range in lithology and chemistry of the source materials from which the Kapoeta meteorite is derived. The data obtained are compared to those from other meteorite and lunar samples, with particular reference to the observational consequences for the evolution of the Kapoeta parent body. A major conclusion is that there is no clearcut evidence for young magmatism on the Kapoeta parent body. The observations preclude the interpretation that the Kapoeta is a simple mixture of eucrites and diogenites. In contrast to the moon, a source of anorthositic rocks does not appear to have been present on the Kapoeta parent body which involved chiefly pyroxene. The FeO-MnO relationships suggest that the source of the materials in the Kapoeta parent planet are fundamentally related.

Dymek, R. F.↗