Digital Commons Network^™

A Geomagnetic Smallsat Observatory For Operation In A 200 Km Altitude Low Earth Orbit, W.R. Baron, K.S. Schultz, P.L. Thomsen

Small Satellite Conference

An altitude of 200 km can improve the accuracy of measurements of the earth's crustal fields and low altitude ionospheric currents. However, atmospheric drag at this altitude requires altitude maintenance to provide useful orbital lifetime. In this study, a small-satellite conceptual design is developed to meet those requirements. The box shaped satellite basic configuration consists of science and electronics module mounted above a propulsion module. Overall satellite body size is 0.71 m x 0.71 m x 1.58 m long. The science and electronics module accommodates an 8 meter long deployable, non-magnetic boom carrying a scalar magnetometer, a star imager and …

Spartan Lite Status Report, S.C. Meyers

Small Satellite Conference

Spartan Lite is an inexpensive, three axis, fine pointer with mission unique pointing capabilities to arc seconds. It is a low cost, class D, single string, spacecraft designed to be launched from a Hitchhiker eject system on the Shuttle or as multiple payloads on a Pegasus class vehicle. The science payload is a cylinder 14 inches in diameter, 28 inches long, and weighing 75 pounds with 40 watts of experiment power. The spacecraft electronics wrap around the payload. Solar arrays are rigidly deployed at one end in a "Flower Petal" configuration. Attitude control actuators and sensors and antennas are mounted …

A Non-Standard Production Approach To Satellite Consellations, John Brunschwyler, Kyle Kelly, Kim Kubota

Small Satellite Conference

A non-standard approach solves several problems encountered in the production of commercial constellations consisting of relatively large numbers of spacecraft. In a commercial environment, market pressures drive the need for a rapid production schedule and highly reliable satellites. This dictates a departure from a conventional spacecraft production process.

The ORBCOMM spacecraft program has developed a singular approach to spacecraft production. This new approach consists of three major elements: 1) On-line Production Process: On-line procedures guide the production process. The engineers input procedure modifications directly into the database that are then immediately accessible. The process incorporates on-line nonconformance reporting. Integrated quality …

Parametric Design Curves For Payload Power And Mass Capabilities Of Non-Geo Smallsats Buses/Launchers, Gareth Richardson, Nizar Sultan, Alfred Ng

Small Satellite Conference

There is a need to reduce cost and perform an optimization on smallsats and standardsats before options for a payload/bus/launch vehicle combination are selected. Bus manufacturers want naturally to protect their proprietary data; at the same time, a smallsat designer cannot decide on this combination without tradeoff analysis. Geosynchronous bus manufacturers realized, some time ago, that it was in their interests to release some of the payload trade-off curves to potential customers. This paper provides a methodology to reduce cost and optimize the selection of this combination, for Low & Medium earth orbits satellites. This generalized approach for elliptical orbits, …

A Simplified Use Of Quality Function Deployment As A System Tool For Designing To Cost, Steven Deal, V. Coverstone-Carroll

Small Satellite Conference

The problem of designing to cost is one with which industry is still grappling. A technique of requirement development, analysis, and refinement is applied to a university-class satellite development project. A simplified form of the Quality Function Deployment process was followed and allowed to structure the entire design process. It aided in evolving a mission scope which resulted in a feasible mission. This paper presents the steps developed for a senior-level, spacecraft design course. Its application to the design of a low-cost wireless power transmission experiment will be illustrated from requirements generation well into the satellite design. Cost was the …

What's The Price Of Low Cost?, James Wertz, Simon Dawson

Small Satellite Conference

Many programs presented at prior USU meetings have been exceptionally successful at reducing the cost of space missions. Typically this is done by a variety of mechanisms that change fundamental characteristics of how business is done in space. (The missions flown do not literally reproduce their more expensive predecessors, or they would have not have been able to significantly reduce cost.) Thus, a critical question arises, what is the price of low cost? What do we give up in order to achieve the advantage of dramatically lower cost? This paper examines the 10 case study space missions presented in the …

Powering Small Satellites With Advanced Nih2 Dependent Pressure Vessel (Dpv) Batteries, Dwight Caldwell, Chris Fox, Lee Miller

Small Satellite Conference

The Dependent Pressure Vessel (DPV) nickel-hydrogen (NiH2) design is being developed by Eagle-Picher Industries, Inc. (EPI), as a spacecraft battery for both large and small, military and commercial satellites. The DPV cell design offers high specific energy, energy density and reduced cost, while retaining the established IPV technology flight heritage and database. This advanced design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduced parts count. The geometry of the DPV cell promotes compact, minimum volume packaging and battery weight efficiency. The DPV battery design offers significant cost and weight savings potential while …

Structural Design Of The Brazilian Scientific Applications Satellite 1 (Saci-1), P.N. Desouza, W.K. Takahashi, M. Kataoka Filho, M.S. Ribeiro, S.E.C. Varotto, J.A.C.F. Neri

Small Satellite Conference

This paper describes the structural design and analysis of the Brazilian Scientific Applications Satellite (SACI-1) that is devised as a multipurpose bus for scientific applications. The structure includes a Mainbody (Platform and Payload), an Adapter, four deployable panels and the holddown and release mechanisms (HDR). Its overall shape resembles a parallelepiped measuring 600 x 400 x 400 mm (Main body only) and weighting about 65 kg (Mainbody plus Adapter). The Platform consists on a pack of 9 aluminum ribbed frames of different thickness stacked horizontally and connected by means of 12 stud bolts. The Payload is assembled on the top …

Picosat Free Flying Magnetometer Experiment, Dana Clarke, Michael Hicks, Alissa Fitzgerald, Jason Suchman, Robert Twiggs, J. Randolf, Thomas Kenny

Small Satellite Conference

Individual satellites have been measuring the Earth's magnetic field since 1958. Measurements taken in this way have led to some interesting discoveries about the earth's magnetosphere. However, they have also raised many questions about the magnetosphere's finer texture and dynamic nature. Researchers at JPL have proposed a mission where a single larger satellite ejects several picosatellites in order to simultaneously sample a volume of space. Each picosat is to carry a small, two axis, fluxgate magnetometer, several photo detectors for spin rate detection, a micro processor and a high frequency transmitter. After launch from the main satellite, each picosat will …

Key Technological Solutions Towards The Saci-1 Microsatellite Design, J.A.C.F. Neri, S. Rabay, W.A. Dos Santos, P.N. De Souza, I.M. Fonseca, A.R. De Paula Junior

Small Satellite Conference

The advantages of a small scale space program over its bulky and complex space counterparts have been extensively documented in the technical literature. These systems are carrying on affordable solutions to telecommunications, earth observation, small-scale space science besides their direct effects in improving general education and training. Cost-effectiveness with reciprocity of mission needs is the utmost driving factor brought up in the process design. Hence the emphasis of this paper is on the key technical solutions adopted in the SACI microsatellite program currently under development by INPE, in Brazil. SACI-1, which stands for Scientific Applications Satellite, is a 60 kg …

Smex·Lite - Nasa's Next Generation Small Explorer, James Watzin

Small Satellite Conference

High space mission costs continue to be a major problem for the aerospace community. The National Aeronautics and Space Administration (NASA) Small Explorer (SMEX) Project has made great strides in reducing mission costs by implementing a building block architecture and streamlined mission operations. The project aims to substantially reduce both spacecraft and mission costs further through the introduction of advanced design tools and an advanced technology "function-sliced" architecture. Spacecraft autonomy will be extended such that classical mission operations will be eliminated altogether. This paper will describe the fundamental elements of the planned cost reduction and the "function-sliced" architecture as well …

The Mars Microprobe Mission: A Unique Solution For Network Science, George Powell, Sarah Gavit

Small Satellite Conference

The second deep-space advanced technology validation mission in NASA's New Millennium Program will demonstrate planetary microprobe technologies. Two microprobes, each consisting of a very low-mass aeroshell and penetrator system, are planned to launch in January 1999 and arrive at Mars in December 1999. The 2 kg probes ballistically enter the martian atmosphere at 7.2 km/s and passively orient themselves to meet peak heating and impact requirements. Upon impacting the martian surface at a velocity around 200 mis, the probes will punch through the entry aeroshell and separate into a fore and aftbody system. The forebody will reach a depth of …

Revolutionary Next Generation Small Satellite Communications Missions And Architectures, James Stuart

Small Satellite Conference

This paper describes revolutionary next generation small satellite communications missions and architectures. The satellite communications revolution background, current GSO's, 'Little', 'Big' and 'Broadband' LEO's, and enabling satellite technologies are briefly discussed. Converging technological and economic forces drive us inevitably to the next decade's communication satellite systems and network architectures. The increasing pace of new capabilities, Moore's law, and convergence of key technologies over the next few years provide the next generation satellite revolution 'push', while the global and local commercial communications demand/economics, orbit slot and spectrum scarcity, rapidly dropping communications costs, privatization, multiple market entries and competitive shakeouts provide the …

The Near Discovery Mission: Lessons Learned, R.H. Maurer, A.G. Santo

Small Satellite Conference

Under a contract from NASA The Johns Hopkins University Applied Physics Laboratory built and launched a spacecraft that will rendezvous and orbit the near earth asteroid 433 Eros. The Near Earth Asteroid Rendezvous (NEAR) spacecraft is the first under NASA's Discovery Program, which is a series of low cost solar system missions. While in orbit around Eros the spacecraft will measure the bulk, surface, and internal properties of the asteroid for 10 months. This paper describes the lessons learned from design, test, and fabrication that are appropriate to other programs in quick development, or of an interplanetary nature.

Gps Based Attitude Determination: The Rex Ii Flight Experience, Douglas Freesland, Keith Reiss, David Young, Jon Cooper, Captain Andrew Adams

Small Satellite Conference

A milestone in the annals of satellite guidance, navigation and control was achieved as REX II became the first spacecraft to employ GPS attitude knowledge for closed-loop control. Successfully launched and activated on March 8, 1996, this highly capable, low cost, 242 lb spacecraft, uses a GPS receiver to provide the attitude knowledge required by the control system to maintain a three-axis nadir pointed orientation. This paper describes the spacecraft, its attitude control subsystem and by evaluating its early flight history, captures our on-orbit experience using GPS. The resulting combination of GPS attitude knowledge coupled with our simple yet elegant …

Orbcomm Satellites Launch And Initial Flight Operations, David Steffy

Small Satellite Conference

The ORBCOMM Flight Model (FM) 1&2 and MicroLab I spacecraft were flawlessly launched by a Pegasus® vehicle on April 3, 1995. Following sequential separation from the Pegasus third stage, the spacecraft deployed solar arrays and antenna assemblies, autonomously de-tumbled, and acquired sun-nadir attitude. Both ORBCOMM spacecraft connected automatically with a Gateway Earth Station (GES) about 8 hours after launch. Nominal early passes focused on post-launch housekeeping tasks. However, a series of anomalies developed: including loss of gateway uplink, gateway downlink transmitter oscillation, poor GPS position fixing, subscriber downlink transmitter lock-up, and several software problems. All these conditions were unique to …

Mightysat I: Technology In Space For About A Nickel ($M), R.J. Davis, Capt J.F. Monahan, T.J. Itchkawich

Small Satellite Conference

MightySat is a United States Air Force (USAF) Phillips Laboratory (PL) multi-mission, small satellite program dedicated to providing frequent, inexpensive, on-orbit demonstrations of high payoff space system technologies. PL is the USAF center for space technology research & development. MightySat platforms provide the on-orbit "lab bench" for responsively testing emerging technologies to ensure their readiness for operational Air Force missions. This paper focuses on the MightySat I vehicle, developed largely by CTA Space Systems (CTASS) in McLean, VA. MightySat I, also 150 lb satellite designed for ejection from the Space Shuttle, is now in final integration and testing just 15 …

The Space Technology Research Vehicles: Strv-1a,B,C&D, Cdr. Richard Blott, Nigel Wells

Small Satellite Conference

The paper presents an overview of the achievements of the Space Technology Research Vehicle (STRV) 1a&b micro satellite mission in geostationary transfer orbit (GTO). Launched in June 1994 as auxiliary passengers on an Ariane-4, the two satellites achieved their primary objectives of demonstrating new space technologies and techniques in a harsh radiation environment at low cost and in a short timescale. The follow-on mission: STRV 1c&d will also be designed and built by the UK Defence Research Agency at Farnborough and the mission is described in detail. The proposed science and technology pay load, sponsored by the UK Ministry of …

Combined Bronchoalveolar-Vascular Casting Of The Canine Lung, John A. Nettum

Scanning Microscopy

Canine bronchoalveolar and vascular corrosion casts were prepared using unfixed tissue and Dow-Corning Room Temperature Vulcanizing Silastic® 734. The casts were observed using stereo light microscopy and scanning electron microscopy. The casts show the relationship between the vasculature and airway and demonstrate intricate microanatomical details. Also, microvasculature filling was enhanced using unfixed tissue as compared to my previously described technique using fixed tissue. Prewashing the microvasculature with cold phosphate buffered saline appeared to facilitate microvascular filling with silicone rubber. The described method is useful for rapidly making durable models for studying the normal respiratory airway and microvasculature. It should be …

Proceedings From The 33rd Annual Italian And Specialty Cheese Seminar, Various Authors

Cheese Industry Conference

No abstract provided.

Sharing Common Ground On Western Rangelands: Proceedings Of A Livestock/Big Game Symposium, Keith E. Evans, Intermountain Research Station, Usdsa Forest Service, U.S. Department Of Commerce, United States Department Of Agriculture, Forest Service

All U.S. Government Documents (Utah Regional Depository)

This proceedings includes 37 papers and posters presented at the "Sharing Common Ground" symposium. The information represents the progress made in livestock/big game management since the 1991 symposium with the theme of "Seeking Common Ground." The broad range of topics includes the rangeland resource, the science of livestock/big game interactions, the human dimension, and the success stories from the seeking common ground partnership demonstration projects.

The Role Of Calcium In The Regulation Of Apoptosis, David J. Mcconkey

Scanning Microscopy

The recognition that apoptosis is regulated by an evolutionarily conserved set of polypeptides from the nematode Caenorhabditis elegans to humans suggests that a conserved set of biochemical mechanism(s) may also be involved in the response. Early evidence suggested that the endogenous endonuclease implicated in apoptosis in most model systems is Ca2+ -dependent, and subsequent work from a number of independent laboratories suggests that alterations in cytosolic Ca2+ homeostasis are one of the conserved biochemical pathways regulating the response. Molecular targets for Ca2+ are now being identified and include signal transduction intermediates, endonuclease(s) and proteases, and the enzymes involved in the …

Labeling With Nanogold And Undecagold: Techniques And Results, James F. Hainfeld

Scanning Microscopy

A significant new development in gold labeling for microscopy has been achieved through the use of gold cluster compounds that are covalently attached to antibodies or other probe molecules. These unique gold probes are smaller than most colloidal gold conjugates and exhibit improved penetration into tissues, higher labeling densities, and allow many new probes to be made with peptides, nucleic acids, lipids, drugs, and other molecules. A new fluorescent-gold conjugate is useful for examining localization by fluorescence microscopy, then visualizing the same label at the ultrastructural level in the electron microscope.

Cytoskeletal Changes During Radiation-Induced Neoplastic Transformation Of Human Prostate Epithelial Cells, S. C. Prasad, P. J. Thraves, J. S. Rhim, M. R. Kuettel

Scanning Microscopy

We recently reported tumorigenic transformation of SV 40-immortalized neonatal human prostate epithelial cells (267Bl) by exposure to fractionated doses of X-rays. Altered morphology and anchorage independence were observed following two successive fractions of 2 Gy each (F3-SAC). Additional 2 Gy treatments to these non-tumorigenic cells to a total dose of 30 Gy resulted in radiation-transformed tumorigenic colonies (267Bl-SXR). Malignant transformation of parental 267B 1 cells was also achieved by consecutive 2 Gy exposures to a total dose of 30 Gy (267Bl-XR). This study discusses the cytoskeletal changes in the F3-SAC, 267Bl-XR and 267Bl-SXR derivatives of these human prostate epithelial cells. …

Pre-Embedding Staining Of Single Muscle Fibers For Light And Electron Microscopy Studies Of Subcellular Organization, Evelyn Ralston, Thorkil Ploug

Scanning Microscopy

Skeletal muscle fibers are large, multinucleated cells which pose a challenge to the morphologist. In the course of studies of the distribution of the glucose transporter GLUT4, in muscle, we have compared different preparative procedures, for both light (LM) and electron microscopy (EM) immunocytochemistry. Here we show that pre-embedding staining of single teased fibers, or of single enzymatically dissociated fibers, has several advantages over the use of sections for observing discrete patterns that extend over long distances in the cells. We report on an optimization study carried out to establish fixation and permeabilization conditions for EM immunogold labeling of the …

Ph Control Of Monoraphidium Minutum Grown In A Batch Culture Environment, Stephen M. Laconte, Kathryn G. Zeiler

Utah Space Grant Consortium

Research at the National Renewable Energy Laboratory (NREL) is being conducted to develop low-cost technology for coupling the exhaust from fossil fuel-fired power plants to the growth of microalgae for the dual purpose of recycling carbon dioxide emissions and producing a renewable fuel source. Microalgae are unicellular photosynthesizers with tremendous potential for rapid division (growth) and high lipid production. The carbon assimilated into lipids provides a renewable source for biodiesel fuel. Experiments are being conducted to explore the growth rates of microalgae exposed to simulated flue gas. Interest is focused on the effectiveness of pH control for regulating gas dosage …

Geophysical Modeling Error In Wind Scatterometry, Paul E. Johnson, David G. Long

Utah Space Grant Consortium

A scatterometer is a satellite-borne instrument designed to measure wind over the ocean. Scatterometer wind retrieval is based on the relationship between the wind over the ocean and the resulting scattering cross section of the surface; this relationship, termed the "geophysical model function," maps the wind speed, relative wind direction (relative to the antenna azimuth angle), antenna incidence angle, polarization and frequency band to the scattering cross section. The sea surface temperature, salinity, long waves, wind variability within a scatterometer footprint, etc., lend variability to the backscatter. A particular observation of the wind-dependent backscatter can be viewed as a random …

Observation Of A Quasi 16-Day Oscillation In The Polar Summer Mesosepheric Temperature, P. J. Espy, G. Witt

Space Dynamics Laboratory Publications

Night-Time measurements of te hydroxyl Meinel (3,1) Rotational band were used to infer the mesospheric temperature over Scandinavia from June through August, 1992. The Resulting Temperature Time Series Showed Spectrally-Distinct, Statistically-Significant fluctuations with periods between 2 and 16 days, although only the 16-day oscillation will be discussed here. The Perio, amplitude and temporal history of this wave agree with model predictions and radar wind measurm=ements of the (1,3) Rossby normal mode, and are therfore consistent with its identification as the temperature signature of this mode. The relationship of these summer temperature oscillations and the occurence of noctilucent clouds is discussed.

Ion Beam Induced Charge Microscopy Of Integrated Circuits, M. B. H. Breese

Scanning Microscopy

The ion beam induced charge (IBIC) microscopy technique has recently been developed as a means of imaging the depletion regions of working microelectronic devices beneath their thick metallisation and passivation layers. IBIC microscopy is analogous to electron beam induced current microscopy but has the advantages of a larger analytical depth, lower lateral scattering of the incident focused MeV ion beam and negligible charging effects. These characteristics enable IBIC to image small, buried active device regions without the need to remove the surface layers prior to analysis. The basis of this new technique is outlined and the applications for integrated circuit …

Reproductive Ecology, Population Genetics, And Clonal Distribution Of The Narrow Endemic: Mirabilis Macfarlanei (Nyctaginaceae), Jennifer L. Barnes

Biology

I examined the reproductive biology and population genetics of the narrow endemic, Mirabilis macfarlanei (Nyctaginaceae) Constance and Rollins, from the Snake and Salmon Rivers in Idaho and Oregon. The results of this study provide further evidence for the proposed effects of rarity on plant reproductive systems and population genetics. Breeding system results indicated that M. macfarlanei is self-compatible, but requires a pollen vector for fertilization. Seed set was not pollen limited, but may be resource limited during others. The major floral visitors were long-tongued bees such as Anthophora spp. and Bombus spp., unlike other species of Mirabilis, which are …