Search NASA⌕ Search

SEARCH · Search NASA

Results for “scientific instruments”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

An innovative design for autonomous backup attitude control of the Gamma Ray Observatory

The Gamma Ray Observatory is a NASA funded three-axis stabilized spacecraft which will carry four scientific instruments to observe gamma ray phenomena. The requirement to protect the scientific mission from system failures led to the attitude control and determination system design described in this paper. The design employs nine control modes with error detection, hardware substitution, and autonomous mode switching. The system architecture evolved to eliminate cross-dependence between the primary on-board computer (OBC) and the backup control processor electronics. Cross strapping of sensors and actuators and separation of the input/output electronics ensure that a reliable set of sensors and actuators will be available for backup mode operation. The OBC software includes failure detection, hardware reconfiguration, and mode switching logic which provide the ability to autonomously transfer, upon anomaly, to a reliable backup mode. Verification of this mode transition design is done in four test programs: at the unit level, by analytical simulation, by a hybrid breadboard electronics-simulation setup, and by a flight hardware-simulation test.

Tai, F.↗
NASA NTRS1992

Mirror Measurement Device

A Small Business Innovation Research (SBIR) contract led to a commercially available instrument used to measure the shape profile of mirror surfaces in scientific instruments. Bauer Associates, Inc.'s Bauer Model 200 Profilometer is based upon a different measurement concept. The local curvature of the mirror's surface is measured at many points, and the collection of data is computer processed to yield the desired shape profile. (Earlier profilometers are based on the principle of interferometry.) The system is accurate and immune to problems like vibration and turbulence. Two profilometers are currently marketed, and a third will soon be commercialized.

Source record↗
NASA NTRS2005

Sensors for Pointing Moving Instruments Toward Each Other

Optoelectronic sensor systems are being developed for use in maintaining fixed relative orientations of two scientific-instrument platforms that are in relative motion. In the original intended application, the platforms would be two spacecraft flying in formation and separated by a long baseline. In principle, sensor systems of this type could also be used in terrestrial applications for maintaining alignments between moving instrument platforms. The sensor system would utilize beacon laser beams that would be transmitted by the platforms in the normal course of scientific measurements. The frequency of the returned laser beam would differ by about 5 MHz. On each platform, the transmitted laser beam and the laser beam bounced off the other platform would be focused onto a quadrant photodetector, where the interference between the laser beams would give rise to sinusoidal (beat-frequency) signals on all four quadrants. The differences among the phases of the beat-frequency signals in the quadrants would depend on, and would be used to determine the angle between, the wave fronts of the outgoing and incoming laser beams.

Liebe, Carl↗
NASA NTRS2004

Lessons Learned from the Hubble Space Telescope (HST) Contamination Control Program

Over the past two decades, the Hubble Space Telescope (HST) Contamination Control Program has evolved from a ground-based integration program to a space-based science-sustaining program. The contamination controls from the new-generation Scientific Instruments and Orbital Replacement Units were incorporated into the HST Contamination Control Program to maintain scientific capability over the life of the telescope. Long-term on-orbit scientific data has shown that these contamination controls implemented for the instruments, Servicing Mission activities (Orbiter, Astronauts, and mission), and on-orbit operations successfully protected the HST &om contamination and the instruments from self-contamination.

Hansen, Patricia A.↗
NASA NTRS2004

Lessons Learned from the Hubble Space Telescope (HST) Contamination Control Program

Over the past two decades, the Hubble Space Telescope (HST) Contamination Control Program has evolved from a ground-based integration program to a space-based science-sustaining program. The contamination controls from the new-generation Scientific Instruments and Orbital Replacement Units were incorporated into the HST Contamination Control Program to maintain scientific capability over the life of the telescope. Long-term on-orbit scientific data has shown that these contamination controls implemented for the instruments, Servicing Mission activities (Orbiter, Astronauts, and mission), and on-orbit operations successfully protected the HST from contamination and the instruments from self-contamination.

Hansen, Patricia A.↗
NASA NTRS1973

Instrumentation for the Atmospheric Explorer photoelectron spectrometer

The photoelectron spectrometer (PES) is part of the complements of scientific instruments aboard three NASA Atmosphere Explorer (AE) satellites. The PES measures the energy spectrum, angular distribution, and intensity of electrons in the earth's thermosphere. Measurements of energies between 2 and 500 eV are made at altitudes as low as 130 km. The design, characteristics, and performance of the instrument are described.

Peletier, D. P.↗
NASA NTRS1990

Voyager 2's encounter with the gas giants

The findings made by Voyager 2 as it passed by the gas giants are reviewed. The unexpected problems that had to be overcome during the mission, including receiver failure and scan platform problems, are described. The scientific instrumentation aboard Voyager is briefly examined, and the major types of Voyager scientific investigations and principal investigators are listed. The scientific findings regarding the atmospheres, thermal properties, electromagnetic environments, ring systems, satellite surfaces, body properties, and bulk properties are examined.

Miner, Ellis D.↗
NASA NTRS1991

TOPEX/Poseidon - The ocean topography experiment

The configuration of the TOPEX/Poseidon mission is discussed in an overview of the launch and experimental objectives related to the deployment planned for 1992. The spacecraft carries equipment for radar altimetry and precise orbit determination, and the instruments are expected to provide precise observations of global ocean dynamics. Six scientific instruments are described including the Laser Retroreflector Array, the Tracking System Receiver, and GPS Demonstration Receiver. Also described are the orbit configuration of the satellite, verification of system performance, and the techniques for data processing. The observations from the TOPEX/Poseidon experiment can provide data that is free of sea-level variabilities and describes the general circulation of the ocean and its variability.

Fu, Lee-Lueng↗
NASA NTRSDate not supplied

Reflections on 20 Years of Research on the International Space Station

November 2, 2000 began an era of continuous human presence on the International Space Station (ISS). That first crewed expedition to the ISS had few scientific instruments and facilities to work with, yet managed to conduct 52research investigations. Today, crew oversee upwards of 300 investigations during their time aboard. Indeed, over the past 20 years the ISS has evolved into a robust laboratory with dozens of research facilities, capabilities for the autonomous monitoring and conduct of research, and a growing array of scientific tools available and observational instruments active. As a result, the station has hosted more than 3,000 research investigations generating more than 2,400 scientific publications across every major discipline of science. The ISS Program Science Forum is composed of senior science representatives across the station’s international partnership. It provides multilateral science leadership to the ISS Program. Indeed, ISS research has evolved to become a truly international activity encompassing the participation of more than 4,000 investigators from over 100 countries whose research has been completed or is ongoing. This paper provides an overview of the research and technology development conducted to date and reflects upon the accomplishments, impacts and future direction of ISS research from the perspective of the member organizations of the Program Science Forum. Research areas which have been a focus of ISS research to date and key implications both for future space exploration and scientific advancement are presented. Major Earth benefits derived from ISS research are discussed. Finally, the paper provides insight into areas of emphasis for future research including the maturation of technological capabilities needed for deep space exploration, including lunar exploration programs such as Artemis and future missions to Mars

International Space Station↗
NASA NTRS2011

Carbon Nanotubes on Titanium Substrates for Stray Light Suppression

A method has been developed for growing carbon nanotubes on a titanium substrate, which makes the nano tubes ten times blacker than the current state-of-the-art paints in the visible to near infrared. This will allow for significant improvement of stray light performance in scientific instruments, or any other optical system. Because baffles, stops, and tubes used in scientific observations often undergo loads such as vibration, it is critical to develop this surface treatment on structural materials. This innovation optimizes the carbon nano - tube growth for titanium, which is a strong, lightweight structural material suitable for spaceflight use. The steps required to grow the nanotubes require the preparation of the surface by lapping, and the deposition of an iron catalyst over an alumina stiction layer by e-beam evaporation. In operation, the stray light controls are fabricated, and nanotubes (multi-walled 100 microns in length) are grown on the surface. They are then installed in the instruments or other optical devices.

Hagopian, John↗
NASA NTRS2003

Analytic Method for Computing Instrument Pointing Jitter

A new method of calculating the root-mean-square (rms) pointing jitter of a scientific instrument (e.g., a camera, radar antenna, or telescope) is introduced based on a state-space concept. In comparison with the prior method of calculating the rms pointing jitter, the present method involves significantly less computation. The rms pointing jitter of an instrument (the square root of the jitter variance shown in the figure) is an important physical quantity which impacts the design of the instrument, its actuators, controls, sensory components, and sensor- output-sampling circuitry. Using the Sirlin, San Martin, and Lucke definition of pointing jitter, the prior method of computing the rms pointing jitter involves a frequency-domain integral of a rational polynomial multiplied by a transcendental weighting function, necessitating the use of numerical-integration techniques. In practice, numerical integration complicates the problem of calculating the rms pointing error. In contrast, the state-space method provides exact analytic expressions that can be evaluated without numerical integration.

Bayard, David↗
NASA NTRS2005

Space Qualification of Laser Diode Arrays

Laser instruments have great potential in enabling a new generation of remote-sensing scientific instruments. NASA s desire to employ laser instruments aboard satellites, imposes stringent reliability requirements under severe conditions. As a result of these requirements, NASA has a research program to understand, quantify and reduce the risk of failure to these instruments when deployed on satellites. Most of NASA s proposed laser missions have base-lined diode-pumped Nd:YAG lasers that generally use quasi-constant wave (QCW), 808 nm Laser Diode Arrays (LDAs). Our group has an on-going test program to measure the performance of these LDAs when operated in conditions replicating launch and orbit. In this paper, we report on the results of tests designed to measure the effect of vibration loads simulating launch into space and the radiation environment encountered on orbit. Our primary objective is to quantify the performance of the LDAs in conditions replicating those of a satellite instrument, determine their limitations and strengths which will enable better and more robust designs. To this end we have developed a systematic testing strategy to quantify the effect of environmental stresses on the optical and electrical properties of the LDA.

Troupaki, Elisavet↗
NASA NTRS2008

The INTEGRAL Mission: Status and Science

Since its launch on October 17, 2002, the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) mission has been producing exciting scientific results. I will present a brief overview of the INTEGRAL mission including its complement of scientific instruments and its current operational status. This will set the stage for the scientific talks that follow. I will then discuss opportunities for US investigator participation including the NASA INTEGRAL Guest Investigator Program and support services available through the US INTEGRAL Guest Observer Facility.

Sturner, Steven J.↗
NASA NTRS2022

Understanding Sampling Hardware Cleanliness from Perseverance Lessons Learned, and Forward Approach to Biosignature Missions

The search for biosignatures on other solar system bodies drives the scientific objectives of many ongoing and proposed exploration missions, including the Europa Lander mission concept.[1] The detection of trace and unfamiliar biosignatures in extreme environments necessitates state-of-the-art scientific instrumentation with extraordinary sensitivity – and often, extraordinary susceptibility to terrestrial and spacecraft self-induced contamination vectors.[2] While instruments can be carefully designed to operate remotely at high performance, in situ scientific measurements can only analyze the samples they’re given: samples or sample handling hardware that have been inadvertently tainted by outgassed organic molecules, thruster plume effluents, or other common sources of spacecraft contamination may yield ambiguous or false results. Maintaining and verifying the purity of collected samples and the cleanliness of sample handling hardware throughout the lifecycle of biosignature detection missions like Europa Lander is a primary responsibility of the Contamination Control group at JPL.

Alred, John↗
NASA NTRS1984

Spacelab transitioning to Space Station

The availability of Shuttle and Spacelab makes it possible to fly a new class of scientific instruments. Thus, larger and heavier instruments can be employed, while the return of instruments after a mission provides an opportunity for instrument reconditioning and improvement in preparation for the next flight. In addition, the Shuttle provides a basic pointing capability with its Reaction Control System (RCS) which adjusts the attitude of the entire Shuttle in the desired direction. As part of Spacelab, the European Space Agency (ESA) developed an Instrument Pointing System (IPS). Early mission results are discussed, taking into account the first scientific payload carried on the Shuttle (OSTA-1), the OSS-1 payload, Spacelab 1, Spacelab 2, the Astro payload, Sunlab, and OSTA-3. Future missions are also considered, giving attention to the Solar Optical Telescope (SOT), the Shuttle Infrared Telescope Facility (SIRTF), and the Pinhole Occulter Facility (POF). It is pointed out that a number of the instruments being developed can be modified for operation on the Space Station.

Benson, R. H.↗
NASA NTRS1994

Our Mission to Planet Earth: A guide to teaching Earth system science

Volcanic eruptions, hurricanes, floods, and El Nino are naturally occurring events over which humans have no control. But can human activities cause additional environmental change? Can scientists predict the global impacts of increased levels of pollutants in the atmosphere? Will the planet warm because increased levels of greenhouse gases, produced by the burning of fossil fuels, trap heat and prevent it from being radiated back into space? Will the polar ice cap melt, causing massive coastal flooding? Have humans initiated wholesale climatic change? These are difficult questions, with grave implications. Predicting global change and understanding the relationships among earth's components have increased in priority for the nation. The National Aeronautics and Space Administration (NASA), along with many other government agencies, has initiated long-term studies of earth's atmosphere, oceans, and land masses using observations from satellite, balloon, and aircraft-borne instruments. NASA calls its research program Mission to Planet Earth. Because NASA can place scientific instruments far above earth's surface, the program allows scientists to explore earth's components and their interactions on a global scale.

Source record↗