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In January 2006, the Stardust mission will return the first samples from a solid solar-system body since Apollo, and the first samples of contemporary interstellar dust ever collected. Although sophisticated laboratory instruments exist for the analysis of Stardust samples, techniques for the recovery of particles and particle residues from aerogel collectors remain primitive. Here we describe our recent progress in developing techniques for extracting small volumes of aerogel, which we have called ``keystones,'' which completely contain particle impacts but minimize the damage to the surrounding aerogel collector. These keystones can be fixed to custom-designed micromachined silicon fixtures (so-called ``microforklifts''). In this configuration the samples are self-supporting, which can be advantageous in situations in which interference from a supporting substrate is undesirable. The keystones may also be extracted and placed onto a substrate without a fixture. We have also demonstrated the capability of homologously crushing these unmounted keystones for analysis techniques which demand flat samples.

We performed a series of hypervelocity impact experiments using carbon-bearing impactors (diamond, graphite, fullerenes, phthalic acid crystals, and Murchison meteorite) into Al plate at velocities between 4.2 and 6.1 km/s. These tests were made to do the following: (1) determine the survivability of carbon forms and organize molecules in low hypervelocity impact; (2) characterize carbonaceous impactor residues; and (3) determine whether or not fullerenes could form from carbonaceous impactors, under our experimental conditions, or survive as impactors. An analytical protocol of field emission SEM imagery, SEM-EDX, laser Raman spectroscopy, single and 2-stage laser mass spectrometry, and laser induced fluorescence (LIF) found the following: (1) diamonds did not survive impact at 4.8 km/s, but were transformed into various forms of disordered graphite; (2) intact, well-ordered graphite impactors did survive impact at 5.9 km/sec, but were only found in the crater bottom centers; the degree of impact-induced disorder in the graphite increases outward (walls, rims, ejecta); (3) phthalic acid crystals were destroyed on impact (at 4.2 km/s, although a large proportion of phthalic acid molecules did survive impact); (4) fullerenes did not form as products of carbonaceous impactors (5.9 - 6.1 km/s, fullerene impactor molecules mostly survived impact at 5.9 km/s; and (5) two Murchison meteorite samples (launched at 4.8 and 5.9 km/s) show preservation of some higher mass polycyclic aromatic hydrocarbons (PAHs) compared with the non-impacted sample. Each impactor type shows unique impactor residue morphologies produced at a given impact velocity. An expanded methodology is presented to announce relatively new analytical techniques together with innovative modifications to other methods that can be used to characterize small impact residues in LDEF craters, in addition to other acquired extraterrestrial samples.

The Interplanetary Dust Experiment (IDE) had over 450 electrically active ultra-high purity metal-oxide-silicon impact detectors located on the six primary sides of the Long Duration Exposure Facility (LDEF). Hypervelocity microparticles (approximately 0.2 to approximately 100 micron diameter) that struck the active sensors with enough energy to break down the 0.4 or 1.0 micron thick SIO2 insulator layer separating the silicon base (the negative electrode), and the 1000 A thick surface layer of aluminum (the positive electrode) caused electrical discharges that were recorded for the first year of orbit. The high purity Al-SiO2-Si substrates allowed detection of trace (ppm) amounts of hypervelocity impactor residues. After sputtering through a layer of surface contamination, secondary ion mass spectrometry (SIMS) was used to create two-dimensional elemental ion intensity maps of microparticle impact sites on the IDE sensors. The element intensities in the central craters of the impacts were corrected for relative ion yields and instrumental conditions and then normalized to silicon. The results were used to classify the particles' origins as 'manmade,' 'natural,' or 'indeterminate.' The last classification resulted from the presence of too little impactor residue, analytical interference from high background contamination, the lack of information on silicon and aluminum residues, or a combination of these circumstances. Several analytical 'blank' discharges were induced on flight sensors by pressing down on the sensor surface with a pure silicon shard. Analyses of these blank discharges showed that the discharge energy blasts away the layer of surface contamination. Only Si and Al were detected inside the discharge zones, including the central craters of these features. Thus far a total of 79 randomly selected microparticle impact sites from the six primary sides of the LDEF have been analyzed: 36 from tray C-9 (Leading (ram), or East, side), 18 from tray C-3 (Trailing (wake), or West, side), 12 from tray B-12 (North side), 4 from tray D-6 (South side), 3 from tray H-11 (Space end), and 6 from tray G-10 (Earth end). Residue from manmade debris was identified in craters on all trays. (Aluminum oxide particle residues were not detectable on the Al/Si substrates.) These results were consistent with the IDE impact record which showed highly variable long term microparticle impact flux rates on the West, Space and Earth sides of the LDEF which could not be ascribed to astronomical variability of micrometeorite density. The IDE record also showed episodic bursts of microparticle impacts on the East, North, and South sides of the satellite, denoting passage through orbital debris clouds or rings.

During 2003 and 2004, the Johnson Space Center's White Sands Testing Facility in Las Cruces, New Mexico conducted hypervelocity impact tests on the space shuttle wing leading edge. Hypervelocity impact tests were conducted to determine if Micro-Meteoroid/Orbital Debris impacts could be reliably detected and located using simple passive ultrasonic methods. The objective of Target RCC16R was to study hypervelocity impacts through the reinforced carbon-carbon (RCC) panels of the Wing Leading Edge. Impact damage was detected using lightweight, low power instrumentation capable of being used in flight.

Hypervelocity impacts were performed on six unstressed and six stressed titanium coupons with aluminium: shielding in order to assess the effects of the partial penetration damage on the post impact micromechanical properties of titanium and on the residual strength after impact. This work is performed in support of the defInition of the penetration criteria of the propellant and oxidizer tanks dome surfaces for the service module of the crew exploration vehicle where such a criterion is based on testing and analyses rather than on historical precedence. The objective of this work is to assess the effects of applied biaxial stress on the damage dynamics and morphology. The crater statistics revealed minute differences between stressed and unstressed coupon damage. The post impact residual stress analyses showed that the titanium strength properties were generally unchanged for the unstressed coupons when compared with undamaged titanium. However, high localized strains were shown near the craters during the tensile tests.

As the outlook for space exploration becomes more ambitious and spacecraft travel deeper into space than ever before, it is increasingly important that propulsion systems perform reliably within the space environment. The increased reliability compels designers to increase design margin at the expense of system mass, which contrasts with the need to limit vehicle mass to maximize payload. Such are the factors that motivate the integration of high specific strength composite materials in the construction of pressure vessels commonly referred to as composite overwrapped pressure vessels (COPV). The COPV consists of a metallic liner for the inner shell of the COPV that is stiff, negates fluid permeation and serves as the anchor for composite laminates or filaments, but the liner itself cannot contain the stresses from the pressurant it contains. The compo-site-fiber reinforced polymer (CFRP) is wound around the liner using a combination of hoop (circumferential) and helical orientations. Careful consideration of wrap orientation allows the composite to evenly bear structural loading and creates the COPV's characteristic high strength to weight ratio. As the CFRP overwrap carries most of the stresses induced by pressurization, damage to the overwrap can affect mission duration, mission success and potentially cause loss-of-vehicle/loss-of-crew. For this reason, it is critical to establish a fundamental understanding of the mechanisms involved in the failure of a stressed composite such as that of the COPV. One of the greatest external threats to the integrity of a spacecraft's COPV is an impact from the meteoroid and orbital debris environments (MMOD). These impacts, even from submillimeter particles, generate extremely high stress states in the CFRP that can damage numerous fibers. As a result of this possibility, initial assumptions in survivability analysis for some human-rated NASA space-craft have assumed that any alteration of the vessel due to impact is considered a catastrophic failure. This assumption is conservative and made due to lack of knowledge on the level of allow-able damage to the composite overwrap that can be sustained and still allow successful completion of the mission. To quantify the allowable damage level to the composite overwrap involves assessing stress redistribution following damage as well as evaluating possible time-dependent mechanisms involved in the COPV response to an impact event. Limited published work in this subject has shown that COPV can withstand at least some level of damage due to high energy impacts. These observations have been confirmed and expanded upon in recent experimental research performed by NASA. This research has demonstrated that there is not only robustness in a COPV to compensate for CFRP damage, but has also identified two significant failure modes for pressurized COPV. The lowest threshold failure mode involves the perforation of the vessel, and the highest threshold failure mode is the catastrophic rupture. While both of these failure modes mean a loss of the COPV, system robustness affords some tolerance to the venting as opposed to the more catastrophic rupture. As a consequence, it is necessary to understand the conditions that result in the transition between these failure modes. The aforementioned experimental research has been performed in both the unpressurized and pressurized condition to identify the damage level that triggered the failure thresh-old. This COPV test program was sponsored by the NASA Engineering and Safety Center (NESC), and tests were performed at NASA White Sands Test Facility (WSTF). Planning and coordination were provided by NASA JSC Hypervelocity Impact Technology (HVIT) group, and the COPVs were provided by the ISS Program. Unpressurized testing has been conducted at the pressure of the vacuum test chamber, while, the pressurized testing has been conducted at 290 +/- 10 bar (4,200  100 psi) using nitrogen as the pressurizing gas, which corresponds to the design pressure for the target COPV. In this research, spherical aluminum projectiles with varying diameter has been chosen as the impactor. For the unpressurized COPV, the dependence of penetration up to the dependence of hole size in the liner has been obtained as a function of impact conditions. For the pressurized research, the dependence of penetration up to rupture has been obtained as a function of im-pact conditions. Two representative post-test photographs of the failed COPV's from a nor-mal impact into the COPV surface are shown in Fig. 1. These images display the dramatic difference between failure modes, venting (Fig. 1a) and rupture (Fig. 1b). For venting, liner perforation, severed composite fibers/tows and ply delamination are commonly observed damage characteristics of this COPV failure mode. In the case of rupture, the COPV typically experienced a separation of its domed regions and severe break-up of the cylindrical region. Fully understanding the transition from venting to rupture experimentally is costly and potentially unachievable for conditions that cannot be generated in the laboratory. These shortcomings have motivated the performance of three-dimensional numerical simulations to expand the existing experimental database. These simulations have been carried out with the nonlinear-structural-dynamics, analysis-tool, CTH. A typical pressure contour plot from an impact simulation of an entire COPV is shown in Fig. 2. To generate the COPV stress state without initiating a shock wave, the pressure in the simulated COPV is ramped up to the final pressure over a millisecond prior to impact of the projectile with nitrogen gas. Figure 2a shows the system in this initial condition. After one millisecond, a projectile is initiated into the simulation and impacts the COPV. Figure 2b shows the system after this impact. In the figure, the onset of venting is represented as the change in pressure (μbar), red to green, at the perforation site. Also seen in the figure is the eroded projectile that had passed into the COPV vessel with the generated shock wave in the pressurant propagating just ahead of the material. In this paper, pertinent experimental details and the development of the material constitutive models necessary for this work along with the efforts to validate their use are dis-cussed. The simulation results are presented and compared with the NASA experimental observations. While work is on-going from this effort, early observations pertinent to the failure threshold are presented.

The memorandum discusses the thermodynamics associated with the flow processes in hypervelocity cratering. Qualitative, graphical arguments are presented to show that previously proposed thermal-impact theories, which postulate that the kinetic energy of impacting projectiles goes entirely into breaking of chemical bonds of fusion, considerably overestimate the transference of energy into heating. Work conducted on the evaluation of release temperatures and phases of nine metals as a function of shock strength is summarized, and similar information is estimated for ten additional metals. The data on release temperature as a function of maximum shock pressure provide a basis for calculating the threshold impact velocities of various projectiles that cause incipient and complete melting in the target material. The results indicate that a quantitative evaluation of the effects of heating in an impact process requires a detailed knowledge of the maximum shock pressures as a function of position within the target.

Ultrahigh speed photographic system for photographing hypervelocity projectiles and impact phenomena

Threshold penetration data are established by impacting spherical projectiles onto 2024 aluminum single-wall targets. Nylon and cadmium projectiles were used at impacting velocities from 3.0 to 6.8 km/s and 7.9 to 8.5 km/s respectively. These data are combined with existing data and compared with three threshold relations to assess their respective validities over a wide range of projectile densities. Two of these relations were validated over the extended range of projectile densities.

A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft is described. The spacecraft wall configuration is assumed to consist of multilayer insulation (MLI) placed between a Whipple style bumper and the pressure wall. Predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on Earth. A module of the program facilitates the creation of the data base of experimental results that are used by the damage prediction modules of the code. The user has the choice of three different prediction modules to predict damage to the bumper, the MLI, and the pressure wall. One prediction module is based on fitting low order polynomials through subsets of the experimental data. Another prediction module fits functions based on nondimensional parameters through the data. The last prediction technique is a unique approach that is based on weighting the experimental data according to the distance from the design point.

A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft are described. Spacecraft wall temperatures and condensate formation is also predicted. The spacecraft wall configuration is assumed to consist of multilayered insulation (MLI) placed between a Whipple style bumper and the pressure wall. Impact damage predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on earth. A module of the program facilitates the creation of the database of experimental results that is used by the damage prediction modules to predict damage to the bumper, the MLI, and the pressure wall. A finite difference technique is used to predict temperature distributions in the pressure wall, the MLI, and the bumper. Condensate layer thickness is predicted for the case where the pressure wall temperature drops below the dew point temperature of the spacecraft atmosphere.

In the course of preparing the SD_SURF space debris analysis code, several problems and possibilities for improvement of the BUMPERII code were documented and sent to MSFC. These suggestions and problem reports are included here as a part of the contract final report. This includes reducing BUMPERII memory requirements, compiling problems with BUMPERII, FORTRAN-lint analysis of BUMPERII, and error in function PRV in BUMPERII.

No Abstract Available

Particle-based hydrodynamics models offer distinct advantages over Eulerian and Lagrangian hydrocodes in particular shock physics applications. Particle models are designed to avoid the mesh distortion and state variable diffusion problems which can hinder the effective use of Lagrangian and Eulerian codes respectively. However existing particle-in-cell and smooth particle hydrodynamics methods employ particles which are actually moving interpolation points. The latter distinction has been emphasized in the more recent development of element-free Galerkin theory. As a result general formulations of all of the aforementioned methods are based on the partial differential equation forms of the continuum balance laws which underlie conventional Eulerian and Lagrangian schemes. An alternative modeling methodology, based on the application of Hamilton's equations to a system of deforming physical particles, provides a fully Lagrangian, energy-based approach to shock physics simulations. Neither interpolations of field variables nor continuum balance laws are used to establish the state equations for the particle system. Mechanical and thermal interaction of the particles is accounted for by nonholonomic constraints which determine both particle entropy evolution and particle collision loads. Application of the method is illustrated by simulation of wall shock, Whipple shield, and multi-plate shield impact problems. A three dimensional, vectorized and autotasked implementation of the particle model presented here has been coded for application to orbital debris shield design simulations.

A constitutive microdamage model is developed capable of simulating high shock compression, release, dilatation (tension), and microdamage evolution leading possibly to fracture and penetration of targets after hypervelocity impact. The microdamage constitutive model is applicable to polycrystalline metals and is appropriate in the lower range of hypervelocity impact velocity, i.e. approximately 2-7 Km/s, over which the projectile and target materials remain in the solid state. The model implements the Mie-Omneisen equation of state coupled with the Hugoniot relations along with expressions of non-linear elastic moduli (bulk and shear) as functions of volume strain, temperature and microdamage. The viscoplastic material response includes strain and strain rate hardening and temperature and microdamage softening. The microdamage evolution model is based on the micromechanics of an expanding void, and is capable of modeling void compaction and expansion that leads to spall-fracture as an evolutionary time dependent process. The constitutive microdamage model was implemented in the AutodynTM software and a series of computer simulations of hypervelocity impact experiments on Allloo plates with soda-lime glass spherical projectiles were conducted. The results of the simulations are compared with the laboratory experimental results in terms of crater, penetration hole and back-wall spallation geometry of the target plate.

The DebriSat tests were conducted to better understand the distribution of fragments generated from a hypervelocity impact with a modern satellite. The last such test (SOCIT) was conducted 20 years ago and satellite construction has changed considerably since then. DebriSat was a NASA program with support/collaboration from the Air Force Space and Missile Center, University of Florida and Aerospace. It consisted of three tests: Pre Preshot, Debris-LV and DebriSat. Tests were conducted at the Arnold Engineering Development Complex Range G Two-Stage Light Gas Gun Facility with a pressure of 1-2 Torr of air and using approximately 600 gram projectiles with nominal velocities of 7 km/s. The Pre Preshot target was a multi-shock shield supplied by NASA designed to catch the projectile. It consisted of seven bumper panels consisting of fiberglass, stainless steel mesh and Kevlar. Debris-LV used a 15 kg target fabricated by Aerospace to simulate a spent upper stage. DebriSat consisted of a 50 kg target constructed by the University of Florida from materials representative of a modern LEO satellite.

Contents: A critique of accelerator techniques for hypervelocity impact; Experimental and theoretical studies on the interior ballistics of light gas guns; An investigation of the performance of a compression heater for use with gun tunnels or hypervelocity launchers; Computer analysis of two-stage hypervelocity model launchers; NRL hypervelocity accelerator development; Performance of a three stage arc heated light gas gun; Hypervelocity augmentation techniques.

An improved hybrid particle-finite element method has been developed for hypervelocity impact simulation. The method combines the general contact-impact capabilities of particle codes with the true Lagrangian kinematics of large strain finite element formulations. Unlike some alternative schemes which couple Lagrangian finite element models with smooth particle hydrodynamics, the present formulation makes no use of slidelines or penalty forces. The method has been implemented in a parallel, three dimensional computer code. Simulations of three dimensional orbital debris impact problems using this parallel hybrid particle-finite element code, show good agreement with experiment and good speedup in parallel computation. The simulations included single and multi-plate shields as well as aluminum and composite shielding materials. at an impact velocity of eleven kilometers per second.

This report is a critical investigation of the meteoroid hazard and of theoretical, empirical, and experimental investigations of hypervelocity impact. Simple and complex models of cratering and perforation are considered, as are the limitations and requirements imposed by practical engineering considerations. Results presented in this report are based on a detailed review of the published works of the many investigators in the field of hypervelocity impact and on a number of independent experimental and theoretical research programs being conducted at GM Defense Research Laboratories. The conclusions are summarized, and specific recommendations are made concerning future experimental and theoretical studies of hypervelocity impact.

During 2003 and 2004, the Johnson Space Center's White Sands Testing Facility in Las Cruces, New Mexico conducted hypervelocity impact tests on the space shuttle wing leading edge. Hypervelocity impact tests were conducted to determine if Micro-Meteoroid/Orbital Debris impacts could be reliably detected and located using simple passive ultrasonic methods. The objective of Target C-2 was to study impacts through the reinforced carboncarbon (RCC) panels of the Wing Leading Edge. Fiberglass was used in place of RCC in the initial tests. Impact damage was detected using lightweight, low power instrumentation capable of being used in flight.

Contents: Review of physical processes in hypervelocity impact and penetration, Hydrodynamics of hypervelocity impact, Visco-plastic solution of hypervelocity impact cratering phenomenon, The calculation of stress waves in solids, A hypervelocity impact model for completely deforming projectiles, A blast-wave theory of crater formation in semi-infinite targets, Spherical shock waves and cavity formation in metals, Properties of spherical shock waves produced by hypervelocity impact, Shock front variation in time for high speed impact into water.

This volume contains the papers presented at the 1998 Hypervelocity impact Symposium (HVIS 98) held in Huntsville, Alabama, on November 17-19, 1998. This was the sixth symposium since the re-initiation of the symposia in 1986, and the proceedings for the 1986, 1989, 1992,1994, and 1996 HVIS are published as Volumes 5, 10, 14, 17, and 20, respectively, of the International Journal of Impact Engineering. The 85 papers in this volume address advancements in the basic understanding of hypervelocity impact physics, related phenomenology, and engineering applications. Each paper in this volume has undergone peer review by experts in their respective fields of research. The authors are to be commended for keeping to the schedule for providing their draft manuscripts for review, making appropriate modifications and corrections, and preparing the final manuscript.

The results of the investigations of spray particle impact are reported. A method was devised to measure the velocity an calculate the diameter of the spray particle in light. The crater produced at impact was measured to obtain the diameter and several attempts to measure penetration and volume are described. A scaling law relating macro size craters to micro craters produced at the same velocity is presented.

With three flights remaining on the manifest, the shuttle impact hypervelocity database has over 2800 entries. The data is currently divided into tables for crew module windows, payload bay door radiators and thermal protection system regions, with window impacts compromising just over half the records. In general, the database provides dimensions of hypervelocity impact damage, a component level location (i.e., window number or radiator panel number) and the orbiter mission when the impact occurred. Additional detail on the type of particle that produced the damage site is provided when sampling data and definitive analysis results are available. The paper will provide details and insights on the contents of the database including examples of descriptive statistics using the impact data. A discussion of post flight impact damage inspection and sampling techniques that were employed during the different observation campaigns will be presented. Future work to be discussed will be possible enhancements to the database structure and availability of the data for other researchers. A related database of ISS returned surfaces that are under development will also be introduced.

A design of experiments approach has been implemented using computational hypervelocity impact simulations to determine the most effective place to add mass to an existing metallic Thermal Protection System (TPS) to improve hypervelocity impact protection. Simulations were performed using axisymmetric models in CTH, a shock-physics code developed by Sandia National Laboratories, and validated by comparison with existing test data. The axisymmetric models were then used in a statistical sensitivity analysis to determine the influence of five design parameters on degree of hypervelocity particle dispersion. Several damage metrics were identified and evaluated. Damage metrics related to the extent of substructure damage were seen to produce misleading results, however damage metrics related to the degree of dispersion of the hypervelocity particle produced results that corresponded to physical intuition. Based on analysis of variance results it was concluded that the most effective way to increase hypervelocity impact resistance is to increase the thickness of the outer foil layer. Increasing the spacing between the outer surface and the substructure is also very effective at increasing dispersion.

An improved hybrid particle-finite element method has been developed for the simulation of hypervelocity impact problems. Unlike alternative methods, the revised formulation computes the density without reference to any kernel or interpolation functions, for either the density or the rate of dilatation. This simplifies the state space model and leads to a significant reduction in computational cost. The improved method introduces internal energy variables as generalized coordinates in a new formulation of the thermomechanical Lagrange equations. Example problems show good agreement with exact solutions in one dimension and good agreement with experimental data in a three dimensional simulation.

Quantitative information on hypervelocity impact dynamics was obtained from 30 shots. Cadmium spheres projected at a velocity of 25,000 fps impacted against multiplate targets. Instrumentation used during the test includes five channels of flash X rays, high-speed framing camera, model detectors, impact pressure probes, laser stress-wave sensors, and photostress analyzer. However, data from the pressure measurements and the stress-wave analysis are not included in this report. Some preliminary conclusions made from the test and a few remarks on the experimental techniques are included in this report.

This paper discusses the design of an automated imaging system for size characterization of debris produced by the DebriSat hypervelocity impact test. The goal of the DebriSat project is to update satellite breakup models. A representative LEO satellite, DebriSat, was constructed and subjected to a hypervelocity impact test. The impact produced an estimated 85,000 debris fragments. The size distribution of these fragments is required to update the current satellite breakup models. An automated imaging system was developed for the size characterization of the debris fragments. The system uses images taken from various azimuth and elevation angles around the object to produce a 3D representation of the fragment via a space carving algorithm. The system consists of N point-and-shoot cameras attached to a rigid support structure that defines the elevation angle for each camera. The debris fragment is placed on a turntable that is incrementally rotated to desired azimuth angles. The number of images acquired can be varied based on the desired resolution. Appropriate background and lighting is used for ease of object detection. The system calibration and image acquisition process are automated to result in push-button operations. However, for quality assurance reasons, the system is semi-autonomous by design to ensure operator involvement. This paper describes the imaging system setup, calibration procedure, repeatability analysis, and the results of the debris characterization.

The three principal areas of activity, (1) Numerical solutions of problems in impact, (2) Code development for solving impact problems, and (3) Analytical work on the theory of the impact process, are reviewed, utilizing wherever possible cited papers which have been published during this past year as part of the project work. The investigations covered in these papers are described only briefly in the present status report, familiarity with or availability of the original documents being assumed. The major part of the present discussion is devoted to a status report of unfinished work on the problem of computing strength-dependent and viscous impact flows. A computer program is described for generalizing Eulerian hydrodynamic codes to include these effects and sample calculations are given.

Contents: Observations of crater formation in ductile materials Impact experiments on wax Correlation of hypervelocity impact data Review and analysis of high velocity impact data Hypervelocity launchers and hypervelocity impact experiments at ARDE, Fort Halstead Experimental observations of impact Oblique impact of high velocity steel pellets on lead targets Hypervelocity impact of heated copper Crater characteristics due to impacts between 4 and 15 An experimental investigation of single aluminum meteor bumpers The perforation of thin plates by high velocity fragments Perforation of finite targets by high velocity projectiles Penetration of thin plates

The International Space Station (ISS) must be able to withstand the hypervelocity impacts of micrometeoroids and orbital debris that strike its many surfaces. In order to design and implement shielding which will prevent hull penetration or other operational losses, NASA must first model the orbital debris and micrometeoroid environment. Based upon this environment, special multi-stage shields called Whipple and Enhanced Stuffed Whipple Shields are developed and implemented to protect ISS surfaces. Ballistic limit curves that establish shield failure criteria are determined via ground testing. These curves are functions of material strength, shield spacing, projectile size, shape and density, as well as a number of other variables. The combination of debris model and ballistic limit equations allows NASA to model risk to ISS using a hydro-code called BUMPER. This thesis modifies and refines existing ballistic limit equations for U.S. Laboratory Module shields to account for the effects of projectile (debris/ micro-meteoroid) densities. Using these refined ballistic limit equations this thesis also examines alternative shielding materials and configurations to optimize shield design for minimum mass and maximum stopping potential, proposing alternate shield designs for future NASA ground testing. A final goal of this thesis is to provide the Department of Defense a background in satellite shield theory and design in order to improve protection against micrometeoroid and orbital debris impacts on future spacebased national systems.

A statistical analysis of the NASA Space Shuttle Hypervelocity Impact Database to find correlations between meteoroid and orbital debris (M/OD) impacts on the shuttle orbiter fleet and specific mission parameters; Inclination, Altitude, Duration and Year, M/OD impact data, regardless of location, particle type or mission was examined first, followed by the subcategories of Window data, Radiator data, Reinforced Carbon-Carbon (RCC) data, and Flexible Reusable Surface Insulation (FRSI) data, In an effort to characterize and evaluate the meteoroid and orbital debris (M/OD) environment in low earth orbit, post-flight surveys of the shuttle orbiters are conducted to identify damage caused by hypervelocity impacts from M/OD, Survey analysis determines whether the impactor was a naturally occurring meteoroid or man-made orbital debris, as well as the impactor's size and impact velocity, From the post-flight survey data, calculations on the number of impacts from specific particle diameters or specific particle materials are made and compared to mission parameters to help engineers design spacecraft for better mission efficiency by reducing the effects of M/OD impacts This thesis analyzes the NASA Space Shuttle Hypervelocity Impact Database, using regression analysis software, to find correlations between M/OD impacts on the shuttle orbiter fleet and mission parameters to draw conclusions on what is influencing vehicle damage.

Micrometeorite bombardment of thin foils was simulated by a ballistic method of projecting cast iron particles less than 100 microns in size to 12 km/ sec. The Mylar and Testlar target foils tested were prospective balloon satellite materials. Bare and metal coated specimens, 0.5 and 2 mils thick, were included. Perforations were analysed by a photographic enlargement technique particularly adapted for complete survey of exposed target area without gaps or duplications. Statistical distributions of perforation diameters were obtained and matched with a similar distribution of the impacting fragments. Thus, the integrated impact intensity sustained by a particular target was determined. Results are reported in tabular form suitable for evaluation of changes in physical properties of the foils due to meteorite impact. These experimental methods are suitable for studies of impacts on simple metal foils.

A program was initiated to obtain terminal ballistic data for masses up to five grams starting at velocities of 4.6 km/sec and extending into the hypervelocity region as far as possible. Terminal ballistic data was obtained using aluminum and tungsten carbide projectiles at velocities from near zero to 6.4 km/sec. Both conventional powder guns and light-gas guns were used to obtain this data. Various target materials were examined including lead, steel, copper and two kinds of aluminum, 1100 F and 2014-T6. The data show that for the velocity range and materials considered, the cavity shape approaches that of a hemisphere when the impact is in the hypervelocity region. Also, the ratio of impact energy to crater volume as a function of impact velocity seems to approach a constant value in the hypervelocity region for each projectile-target system except for tungsten carbide into lead.

Gun development efforts to increase the launching capabilities of the NASA Ames 0.5-inch two-stage light-gas gun have been investigated. A gun performance simulation code was used to guide initial parametric variations and hardware modifications, in order to increase the projectile impact velocity capability to 8 km/s, while maintaining acceptable levels of gun barrel erosion and gun component stresses. Concurrent with this facility development effort, a hypervelocity impact testing series in support of the X-33/RLV program was performed in collaboration with Rockwell International. Specifically, advanced thermal protection system materials were impacted with aluminum spheres to simulate impacts with on-orbit space debris. Materials tested included AETB-8, AETB-12, AETB-20, and SIRCA-25 tiles, tailorable advanced blanket insulation (TABI), and high temperature AFRSI (HTA). The ballistic limit for several Thermal Protection System (TPS) configurations was investigated to determine particle sizes which cause threshold TPS/structure penetration. Crater depth in tiles was measured as a function of impact particle size. The relationship between coating type and crater morphology was also explored. Data obtained during this test series was used to perform a preliminary analysis of the risks to a typical orbital vehicle from the meteoroid and space debris environment.

The results of a continuing investigation of the phenomena associated with the oblique hypervelocity impact of spherical projectiles onto multi-sheet aluminum structures are given. A series of equations that quantitatively describes these phenomena is obtained through a regression of experimental data. These equations characterize observed ricochet and penetration damage phenomena in a multi-sheet structure as functions of geometric parameters of the structure and the diameter, obliquity, and velocity of the impacting projectile. Crater damage observed on the ricochet witness plates is used to determine the sizes and speeds of the ricochet debris particles that caused the damage. It is observed that the diameter of the most damaging ricochet debris particle can be as large as 40 percent of the original particle diameter and can travel at speeds between 24 percent and 36 percent of the original projectile impact velocity. The equations necessary for the design of shielding panels that will protect external systems from such ricochet debris damage are also developed. The dimensions of these shielding panels are shown to be strongly dependent on their inclination and on their circumferential distribution around the spacecraft.

Using the concept of intercepting orbits from a pair of Space Station serviced free flyers, a class of impact and shock wave experiments pertinent to planetary science can be performed. One proposed free flying vehicle is an impactor dispensor, and the second is the impact laboratory. How collision is achieved by utilizing essentially twice orbital velocity is demonstrated. The impactor dispensor contains a series of small flyer plates or other projectiles which are launched into the trajectory of the impactor laboratory at appropriate positions. The impactor laboratory is a large impact tank similar to those in terrestrial gun laboratories, except that it contains a supply of targets and instrumentation such as high speed cameras, flash X-ray apparatus, and digital recorders. Shock and isentropic pressures of up to 20 Mbar are achievable with such a system which provides 15 km/sec impact velocities for precisely oriented projectiles.

Ionization associated with hypervelocity impact

An experimental investigation of phenomena associated with the oblique hypervelocity impact of spherical projectiles on multisheet aluminum structures is described. A model that can be employed in the design of meteoroid and space debris protection systems for space structures is developed. The model consists of equations that relate crater and perforation damage of a multisheet structure to parameters such as projectile size, impact velocity, and trajectory obliquity. The equations are obtained through a regression analysis of oblique hypervelocity impact test data. This data shows that the response of a multisheet structure to oblique impact is significantly different from its response to normal hypervelocity impact. It was found that obliquely incident projectiles produce ricochet debris that can severely damage panels or instrumentation located on the exterior of a space structure. Obliquity effects of high-speed impact must, therefore, be considered in the design of any structure exposed to the meteoroid and space debris environment.

Hypervelocity impact tests of 2.5 grains per foot flexible confined detonating chord (FCDC) shielded by a 1 mm thick 2024-T3 aluminum alloy bumper standing off 51 mm from the FCDC were performed. Testing showed that a 6 mm diameter 2017-T4 aluminum alloy ball impacting the bumper at 6.97 km/s and 45 degrees impact angle initiated the FCDC. However, impact by the same diameter and speed ball at 0 degrees angle of impact did not initiate the FCDC. Furthermore, impact at 45 degrees and the same speed by a slightly smaller diameter ball (5.8 mm diameter) also did not initiate the FCDC.

As a result of man's venturing into space, the local debris contributed by his presence exceeds, at some orbital altitudes, that of the natural component. Man's contribution ranges from fuel residue to large derelect satellites that weigh many kilograms. Current debris models are able to predict the growth of the problem and suggest that spacecraft must employ armor or bumper shields for some orbital altitudes now, and that, the problem will become worse as a function of time. The practical upper limit to the velocity distribution is on the order of 40 km/s and is associated with the natural environment. The maximum velocity of the man-made component is in the 14-16 km/s range. The Long Duration Exposure Facility (LDEF) has verified that the 'high probability of impact' particles are in the microgram to milligram range. These particles can have significant effects on coatings, insulators, and thin metallic layers. The surface of thick materials becomes pitted and the local debris component is enhanced by ejecta from the debris spectrum in a controlled environment. The facility capability is discussed in terms of drive geometry, energetics, velocity distribution, diagnostics, and projectile/debris loading. The facility is currently being used to study impact phenomena on Space Station Freedom's solar array structure, other solar array materials, potential structural materials for use in the station, electrical breakdown in the space environment, and as a means of clarifying or duplicating the impact phenomena on the LDEF surfaces. The results of these experiments are described in terms of the mass/velocity distribution incident on selected samples, crater dynamics, and sample geometry.

Hypervelocity impact tests were conducted to simulate the damage that meteoroids will produce in the Shuttle Orbiter leading edge structural subsystem material. The nature and extent of the damage is reported and the probability of encountering meteoroids with sufficient energy to produce such damage is discussed.

Structural damage resulting in hypervelocity impact of a meteorite on a spacecraft is discussed. Of particular interest is the backside spallation caused by such a collision. To treat this phenomenon two numerical schemes were developed in the course of this study to compute the elastic-plastic flow fracture of a solid. The numerical schemes are a five-point finite difference scheme and a four-node finite element scheme. The four-node finite element scheme proved to be less sensitive to the type of boundary conditions and loadings. Although further development work is needed to improve the program versatility (generalization of the network topology, secondary storage for large systems, improving of the coding to reduce the run time, etc.), the basic framework is provided for a utilitarian computer program which may be used in a wide variety of situations. Analytic results showing the program output are given for several test cases.

The instrumentation capabilities of the Arnold Engineering Development Center (AEDC) von Karman Gas Dynamics Facility's (VKF) aeroballistic ranges have been expanded to facilitate studies of hypervelocity impact-related phenomena. Two instrumentation systems for characterizing clouds of debris resulting from impact have been developed and put to use: (1) An extremely high- speed sequential laser photography system provides photographic data describing debris cloud growth characteristics at framing rates from 10,000/sec to 10 to the 7th power/sec. This system can resolve debris particles as small as 0.0001 in. (2) X-ray shadowgraph systems with exposure times of 30 nsec can record debris velocity and mass data and can discern aluminum particles as small as 0. 063 in. and steel particles as small as 0.031 in. Electromagnetic radiation generated by hypervelocity impact can be explored in a variety of ways.

Semi-analytical lethality assessment models fall into one of two general categories: discrete particle models and expanding shell models. Discrete particle models account for and track only a small number of solid fragments in a debris cloud generated by a hypervelocity impact. They are best suited for impact scenarios in which melting and/or vaporization of the projectile and target materials do not occur. Expanding shell models assume that all of the debris cloud material is homogeneously distributed over a uniformly expanding spherical shell in those impact scenarios where melting and/or vaporization of the projectile and target materials do occur. A lethality assessment model that considers the creation and subsequent effects of debris clouds containing all three states of matter is needed. This report describes the results of an investigation into the composition of the material in a debris cloud generated by a hypervelocity projectile impact. The work completed represents the first step in a long-term research program whose overall objective is to develop a general model of the response of a target structure to a hypervelocity impact over the 4-16 kilometers per second impact regime.

Developing aluminum meteoritic simulators for hypervelocity impact test using shaped charges

During 2003 and 2004, the Johnson Space Center's White Sands Testing Facility in Las Cruces, New Mexico conducted hypervelocity impact tests on the space shuttle wing leading edge. Hypervelocity impact tests were conducted to determine if Micro-Meteoroid/Orbital Debris impacts could be reliably detected and located using simple passive ultrasonic methods. This volume contains an executive summary, overview of the method, brief descriptions of all targets, and highlights of results and conclusions.

No Abstract Available

Advanced composites with multi-functional capabilities are of great interest to the designers of aerospace structures. Polymer matrix composites (PMCs) reinforced with high strength fibers provide a lightweight and high strength alternative to metals and metal alloys conventionally used in aerospace architectures. Novel reinforcements such as nanofillers offer potential to improve the mechanical properties and add multi-functionality such as radiation resistance and sensing capabilities to the PMCs. This paper reports the hypervelocity impact (HVI) test results on ultra-high molecular weight polyethylene (UHMWPE) fiber composites reinforced with single-walled carbon nanotubes (SWCNT) and boron nitride nanotubes (BNNT). Woven UHMWPE fabrics, in addition to providing excellent impact properties and high strength, also offer radiation resistance due to inherent high hydrogen content. SWCNT have exceptional mechanical and electrical properties. BNNT (figure 1) have high neutron cross section and good mechanical properties that add multi-functionality to this system. In this project, epoxy based UHMWPE composites containing SWCNT and BNNT are assessed for their use as bumper shields and as intermediate plates in a Whipple Shield for HVI resistance. Three composite systems are prepared to compare against one another: (I) Epoxy/UHMWPE, (II) Epoxy/UHMWPE/SWCNT and (III) Epoxy/UHMWPE/SWCNT/BNNT. Each composite is a 10.0 by 10.0 by 0.11 cm3 panel, consisting of 4 layers of fabrics arranged in cross-ply orientation. Both SWCNT and BNNT are 0.5 weight % of the fabric preform. Hypervelocity impact tests are performed using a two-stage light gas gun at Rice University

Erosive particle impact frequency-dependent mechanisms are examined to determine potentially important spatial and time-dependent interactions which can influence flight and ground test erosion performance. Specific consideration is given to the interaction of incident erosive particles with impact-generated ejecta and to the shielding effect which this interaction can have on the observed material erosion characteristics. It is concluded that debris shielding does not occur to any significant degree in the real flight environment, but could be a potential problem in correlating high concentration range/track test results.

1Winesburg, Ohio

By Sherwood Anderson

Published in 1919, and listed on the Modern Library roster of the 20th century's 100 greatest novels in English, Winesburg, Ohio presents a series of loosely related character studies of the inhabitants of a fictional Midwestern town that together form a novel of unusual unity and vision. The inarticulate and lonely citizens of Winesburg, each with his or her own secret tale to tell, frequently relate those tales to, or through their interactions with, the character of George Willard, a young Winesburg citizen on the cusp of manhood with dreams of becoming a writer. Thus Winesburg tells the story of the townspeople's loneliness and alienation in parallel with the tale of George's own coming of age. The citizens of Winesburg are described obliquely as "grotesques," but as the introductory chapter makes clear, "The grotesques were not all horrible. Some were amusing, some almost beautiful . . ." (Description by Stewart Wills)

2Seven O'Clock Stories

By Robert Gordon Anderson

"Not once upon a time but just now, in a white house by the side of a road, live three happy children. Their mother and father gave them very odd names, for two old uncles and one aunt, which pleased the old people very much. Their names are all written in the big family Bible,--Jehosophat Green, Marmaduke Green, and Hepzebiah Green." So begins this collection of bedtime stories for children, one each night for twenty days, involving these three happy children and their playmates. (Summary by P. Cunningham)

3Security

By Poul William Anderson

“Security” tells the story of a compartmentalized government physicist ordered by secret police to complete experiments aimed at developing a new weapon. He is brought to a hidden space station and put in charge of the project but there are many questions. In a world of spies watching spies it’s sometimes hard to know what’s patriotic. -- Poul Anderson was a Golden Age Science Fiction and Fantasy author. “Security” first appeared in the magazine “Space Science Fiction” in February of 1953 (Summary by Gregg Margarite)

4Chapter Ends

By Poul William Anderson

Far, far in the future the Earth is still spinning around the Sun, on the edge of the galaxy, dozing in obscurity, forgotten by it's trillions of progeny and completely irrelevant. But this doesn't matter to the few millions who still live there in simplicity and quiet happiness. But then interstellar politics dictates that they must all leave Earth because ... well, listen to the story as told by the great Poul Anderson as he explores what the Earth means to humans and to one man in particular. (Summary by Phil Chenevert)

5Spell of the Hawaiian Islands and the Philippines

By Isabel Anderson

Isabel Anderson has written a most interesting travelogue of Hawaii and The Philippines. Actually it is more of a history lesson. Anyone with any interest whatsoever in the South Pacific will find this book very interesting indeed, to note all that has changed since Mrs. Anderson had traveled there. (Summary by William Tomcho)

Eamont was an opium clipper built in Cowes. It was the subject of an 1891 book, A cruise in an opium clipper, by Captain Lindsay Anderson. Eamont was involved in the opening of Japan to foreigners in 1858, serving as a dispatch boat between Nagasaki and Shanghai, and was one of the first vessels to open up a trade with Formosa…. The Eamont was sent on some very dangerous trips. She was one of the first vessels to open up a trade with Formosa, and made the first survey of the port of Taku, which she entered by bumping over the reef in spite of a tremendous surf beating upon it at the time, a most daring performance. And in her efforts to trade with the Formosans she had to withstand the attack of hundreds of armed natives right on top of a typhoon, which she succeeded in riding out on her moorings. But the captain of the Eamont was a famous fighting man, as the Chinese pirates knew to their cost…. The Eamont was also employed in the negotiations for the first commercial treaty with Japan. (See Wikipedia article on Eamont (schooner)) - Summary by Wikipedia and david wales

Anderson served as third officer aboard the Eamont. Eamont was an opium clipper built in Cowes. Eamont was involved in the opening of Japan to foreigners in 1858, serving as a dispatch boat between Nagasaki and Shanghai, and was one of the first vessels to open up a trade with Formosa. The Eamont was employed in the negotiations for the first commercial treaty with Japan. On this occasion she ran into Nagasaki and quietly dropped anchor, in spite of the fact that opposition to the proposed commercial treaty was very strong at the time. On the following morning 150 boat-loads of Japanese attempted to tow her to sea, being evidently ignorant of an anchor's raison d'etre. But though they attempted several similar methods to get rid of her they refrained from any armed attack, and, eventually, her mission was completely successful. This was in 1858, and the Eamont's crew saw many wonderful sights in that tierra incognita. The September Typhoon of 1858 destroyed several well-known opium clippers at Double Island, including the Anonyma, Gazelle, Pantaloon, and Mazeppa. Eamont was anchored off Double Island, with "150 fathoms of chain out and a second anchor backed on it at 60 fathoms." The waves in the anchorage were estimated to be as large as 40 feet, and the Eamont’s crew had to cut away her masts. Eamont was one of only two ships in that anchorage to survive the night, the other being the Hazard. (See Wikipedia article on Eamont (schooner)) (Wikipedia and david wales)

A Voice from Harper's Ferry is the abolitionist testament of Osborne Perry Anderson, the only surviving black participant in the 1859 raid on Harpers Ferry organized by John Brown. The book details the motivations and preparations for the raid, the events that unfolded over several days in October 1859, and Anderson's subsequent escape. It ends with a short selection of poems from various sources honoring Brown and the movement for abolition. (summary by JR Martin)

9Sentiment, Inc.

By Poul William Anderson

The way we feel about another person, or about objects, is often bound up in associations that have no direct connection with the person or object at all. Often, what we call a "change of heart" comes about sheerly from a change in the many associations which make up our present viewpoint. Now, suppose that these associations could be altered artificially, at the option of the person who was in charge of the process.... (from the Blurb)

“The Triumph of the Egg” is a collection of stories and poems by Sherwood Anderson. Abandoning the interconnected quality of his more famous “Winesburg, Ohio,” the author adopts a variety of perspectives and settings while exploring similar themes: personal growth, disillusionment, loneliness, and urban-rural contrast. In the North American Review, critic Lawrence Gilman wrote, “Mr. Anderson has achieved a beauty that irradiates his page.” Though largely overshadowed by that celebrated, earlier book, “The Triumph of the Egg” remains a foundational work for Modernist literature, proven by its winning the first annual Dial Award from the influential journal The Dial.<br /><br /> NOTE TO LISTENERS: The second story in this collection, “I Want to Know Why,” contains language that may be offensive.<br /> (summary by Ben Adams)

11How to Do Chemical Tricks

By A. T. Anderson

While a bit outdated in many of the more complex descriptions of several of the phenomena described, this book is nonetheless still fun and relevant for a person interested in basic chemistry or physics tricks, and the devices built in the book can be easily replicated with more modern materials. The book is split up into many little experiments, tricks, with an explanation on how it works, what's happening, and how to reproduce the effects at home.(summary by Kyle Van DeGlast)

12American Big-Game Hunting

By George S. Anderson, Winthrop Chanler, Oscar F. C. Crocker, Walter Bourchier Devereux, George Bird Grinnell, Arnold Hague, W. D. Pickett, Archibald Rogers, Theodore Roosevelt, Bronson Rumsey, Dean Sage, Roger D. Williams and Owen Wister

The first book published by The Boone and Crockett Club founded by Theodore Roosevelt and George Grinnell, who declared in their Editors Note: "Hunting big game in the wilderness is, above all things, a sport for a vigorous and masterful people. The rifle-bearing hunter, whether he goes on foot or on horseback, whether he voyages in a canoe or travels with a dog-sled, must be sound of body and firm of mind, and must possess energy, resolution, manliness, self-reliance, and capacity for hardy self-help. In short, the big-game hunter must possess qualities without which no race can do its life-work well; and these are the very qualities which it is the purpose of this Club, so far as may be, to develop and foster."<br /><br /> A bit outdated as to the equipment they used, this book is nevertheless an intense look at the west in early days, and at the beginnings of the conservationist movement in America. Each chapter focuses on a different animal, from buffalo, mountain goat, elk, pronghorn sheep, grizzlies, etc., indigenous peoples, different areas like the Rockies and Yellowstone, and it still captures the essence of the spirit of the hunt.<br /><br /> The book ends with a list of the club's original 100 members, a veritable Who's Who of Generals, Colonels, Doctors, Senators and Representatives, amongst them that most illustrious Gen'l William T. Sherman. ( ~ Michele Fry, read by LibriVox Volunteers)

13Windy McPherson's Son

By Sherwood Anderson

Windy McPherson's Son is the story of Sam McPherson's rise in the world of business and search for emotional enlightenment in later life. McPherson starts out as an ambitious newsboy in Caxton, Ohio, with drunkard of a father who constantly embarrasses him. Eventually, after his mother's death and an episode with a middle-aged schoolteacher, McPherson leaves Caxton for Chicago. In Chicago, he gets a job as a buyer of farm implements and establishes his reputation in business. While his professional life is blossoming, his personal life suffers. After meeting Sue Rainey, the daughter of his boss Colonel Rainey, they get married and twice fail to have children. Following a business deal that forces his father-in-law out of his own company, McPherson and Sue Rainey separate. One day, once McPherson had become quite wealthy, he gets a telegram saying that Colonel Rainey committed suicide. This causes Sam to realize that he is unhappy with his life. This feeling inspires him to leave Chicago and travel all over becoming involved in various adventures. Finally, McPherson's comes across a promiscuous and alcoholic mother of three children. A deal is made and McPherson gets custody of the children. Showing up with the children at Sue's current place of residence, the five of them become family. ( Wikipedia)

14Inside Earth

By Poul William Anderson

This story takes place in the not so distant future. Earth has been conquered and is a subjugated planet, the much too humanoid new rulers now extract heavy taxes, control industry and reproduction and interfere in every aspect of life. Rumors of their brutality and vicious massacres increase every day. Obviously, they must be thrown out and rebellion seethes among the patriots. But on the other hand, others are not so eager to get rid of the overlords: the terrible nationalistic wars have been stopped, famine is long gone and health care is almost universally available. Still, the elite intellectual portion of the earth's population plot to remove the heavy heel of the oppressors from their necks and let earth be free again. But time and again the attempts for freedom have been crushed the Valgolians mainly because national, ethnic, religious and racial prejudices and hatred among the earthlings keep the conspirators from working together. Obviously, no conqueror wants his subjects to revolt against his rule. Obviously? This one would go to any lengths to start a rebellion!

15Sensitive Man

By Poul William Anderson

Poul Anderson delves into the realm of human potential in this exciting story and asks some penetrating questions for us to think about. What if psychology finally enabled people to even partially control all those automatic reactions of our minds and bodies? What if we were not slaves to anger, fear, emotions, hormones, blood pressure and the thousand other things that our bodies 'take care of' from instant to instant? What if those things could be brought under the control even partially of our reason and minds? In this story one man stood between a power-hungry cabal and their world mastery—but a man of, shall we say, unusual talents.

16Hunting In Many Lands

By Henry T. Allen, George S. Anderson, Daniel Moreau Barringer, Winthrop Chanler, George H. Gould, Madison Grant, William Woodville Rockhill, Elliott Bulloch Roosevelt, Theodore Roosevelt, Alden Sampson, Henry L. Stimson, Charles E. Whitehead, Caspar W. Whitney and Roger D. Williams

The first volume published by the Boone and Crockett Club, entitled "American Big Game Hunting," confined itself to sport on the American continent. This second volume presents a number of interesting sketches written by club members who have hunted big game in other lands. Essays include: Hunting in East Africa, To the Gulf of Cortez, A Canadian Moose Hunt, A Hunting Trip in India, Dog Sledging in the North, Wolf-Hunting in Russia, A Bear-Hunt in the Sierras, The Ascent of Chief Mountain, The Cougar, Big Game of Mongolia and Tibet, Hunting in the Cattle Country, Wolf-Coursing, Game Laws, and Protection of the Yellowstone National Park. - Summary by Michele Fry

Margaret Steele Anderson was born in Louisville, Kentucky in 1867 and was educated in the public school of Louisville, with special courses at Wellesley College. From 1901 Miss Anderson was Literary Editor of the `Evening Post' of Louisville, and was known as one of the most discriminating critics of the South. She published only one volume of verse, "The Flame in the Wind", 1914. (David Lawrence

Frederick Irving Anderson was a New York newspaperman who had a second career writing mystery stories for the "slick" magazines such as the Saturday Evening Post. The Infallible Godahl is a collection of some of his first stories. Godahl is a clever gentleman thief, who might be thought of as an American version of Raffles or Arsene Lupin. - Summary by Winston Tharp