868 research outputs found

    Space Shuttle Mission STS-61: Hubble Space Telescope servicing mission-01

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    This press kit for the December 1993 flight of Endeavour on Space Shuttle Mission STS-61 includes a general release, cargo bay payloads and activities, in-cabin payloads, and STS-61 crew biographies. This flight will see the first in a series of planned visits to the orbiting Hubble Space Telescope (HST). The first HST servicing mission has three primary objectives: restoring the planned scientific capabilities, restoring reliability of HST systems and validating the HST on-orbit servicing concept. These objectives will be accomplished in a variety of tasks performed by the astronauts in Endeavour's cargo bay. The primary servicing task list is topped by the replacement of the spacecraft's solar arrays. The spherical aberration of the primary mirror will be compensated by the installation of the Wide Field/Planetary Camera-II and the Corrective Optics Space Telescope Axial Replacement. New gyroscopes will also be installed along with fuse plugs and electronic units

    NASA Tech Briefs, May 2012

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    Topics covered include: An "Inefficient Fin" Non-Dimensional Parameter to Measure Gas Temperatures Efficiently; On-Wafer Measurement of a Multi-Stage MMIC Amplifier with 10 dB of Gain at 475 GHz; Software to Control and Monitor Gas Streams; Miniaturized Laser Heterodyne Radiometer (LHR) for Measurements of Greenhouse Gases in the Atmospheric Column; Anomaly Detection in Test Equipment via Sliding Mode Observers; Absolute Position of Targets Measured Through a Chamber Window Using Lidar Metrology Systems; Goldstone Solar System Radar Waveform Generator; Fast and Adaptive Lossless Onboard Hyperspectral Data Compression System; Iridium Interfacial Stack - IrIS; Downsampling Photodetector Array with Windowing; Optical Phase Recovery and Locking in a PPM Laser Communication Link; High-Speed Edge-Detecting Line Scan Smart Camera; Optical Communications Channel Combiner; Development of Thermal Infrared Sensor to Supplement Operational Land Imager; Amplitude-Stabilized Oscillator for a Capacitance-Probe Electrometer; Automated Performance Characterization of DSN System Frequency Stability Using Spacecraft Tracking Data; Histogrammatic Method for Determining Relative Abundance of Input Gas Pulse; Predictive Sea State Estimation for Automated Ride Control and Handling - PSSEARCH; LEGION: Lightweight Expandable Group of Independently Operating Nodes; Real-Time Projection to Verify Plan Success During Execution; Automated Performance Characterization of DSN System Frequency Stability Using Spacecraft Tracking Data; Web-Based Customizable Viewer for Mars Network Overflight Opportunities; Fabrication of a Cryogenic Terahertz Emitter for Bolometer Focal Plane Calibrations; Fabrication of an Absorber-Coupled MKID Detector; Graphene Transparent Conductive Electrodes for Next- Generation Microshutter Arrays; Method of Bonding Optical Elements with Near-Zero Displacement; Free-Mass and Interface Configurations of Hammering Mechanisms; Wavefront Compensation Segmented Mirror Sensing and Control; Long-Life, Lightweight, Multi-Roller Traction Drives for Planetary Vehicle Surface Exploration; Reliable Optical Pump Architecture for Highly Coherent Lasers Used in Space Metrology Applications; Electrochemical Ultracapacitors Using Graphitic Nanostacks; Improved Whole-Blood-Staining Device; Monitoring Location and Angular Orientation of a Pill; Molecular Technique to Reduce PCR Bias for Deeper Understanding of Microbial Diversity; Laser Ablation Electrodynamic Ion Funnel for In Situ Mass Spectrometry on Mars; High-Altitude MMIC Sounding Radiometer for the Global Hawk Unmanned Aerial Vehicle; PRTs and Their Bonding for Long-Duration, Extreme-Temperature Environments; Mid- and Long-IR Broadband Quantum Well Photodetector; 3D Display Using Conjugated Multiband Bandpass Filters; Real-Time, Non-Intrusive Detection of Liquid Nitrogen in Liquid Oxygen at High Pressure and High Flow; Method to Enhance the Operation of an Optical Inspection Instrument Using Spatial Light Modulators; Dual-Compartment Inflatable Suitlock; Large-Strain Transparent Magnetoactive Polymer Nanocomposites; Thermodynamic Vent System for an On-Orbit Cryogenic Reaction Control Engine; Time Distribution Using SpaceWire in the SCaN Testbed on ISS; and Techniques for Solution- Assisted Optical Contacting

    Science & Technology Review December 2005

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    Image-Processing Techniques for the Creation of Presentation-Quality Astronomical Images

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    The quality of modern astronomical data, the power of modern computers and the agility of current image-processing software enable the creation of high-quality images in a purely digital form. The combination of these technological advancements has created a new ability to make color astronomical images. And in many ways it has led to a new philosophy towards how to create them. A practical guide is presented on how to generate astronomical images from research data with powerful image-processing programs. These programs use a layering metaphor that allows for an unlimited number of astronomical datasets to be combined in any desired color scheme, creating an immense parameter space to be explored using an iterative approach. Several examples of image creation are presented. A philosophy is also presented on how to use color and composition to create images that simultaneously highlight scientific detail and are aesthetically appealing. This philosophy is necessary because most datasets do not correspond to the wavelength range of sensitivity of the human eye. The use of visual grammar, defined as the elements which affect the interpretation of an image, can maximize the richness and detail in an image while maintaining scientific accuracy. By properly using visual grammar, one can imply qualities that a two-dimensional image intrinsically cannot show, such as depth, motion and energy. In addition, composition can be used to engage viewers and keep them interested for a longer period of time. The use of these techniques can result in a striking image that will effectively convey the science within the image, to scientists and to the public.Comment: 104 pages, 38 figures, submitted to A

    Advanced photonic solutions for high precision astronomical imaging

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    The sharply rising productivity of exoplanet searches over the past two decades has delivered profound statistical insights into the prevalence and diversity of worlds around other stars. The frontier for astronomers has now expanded into the new era of exoplanet characterisation. Major progress here will only be achieved with new instrumental advances. Most highly sought-after is the capability to separate the faint light from a planet from the glare of the host star. The direct detection of planetary photons will enable unique spatial and spectral studies, revealing intrinsic properties of atmospheres and surfaces. In this project, a prototype instrument GLINT South (Guided Light Interferometric Nulling Technology) was developed. It employs nulling interferometry in which the light from the host star is actively rejected though destructive interference. Such advanced control and processing of starlight is accomplished by way of photonic technology fabricated into integrated optical chips. A monochromatic null depth was measured in the laboratory consistent with 0 within an uncertainty of 10-3. The instrument was tested at the Anglo Australian Telescope, and a sample of infrared-bright stars were observed retrieving uniform disk diameters in close agreement to the literature values, despite the stellar diameters being beyond the telescopes formal di raction limit. Furthermore, an algorithm was created to optimise the design of integrated optics waveguides for pupil remapping chips leading to the design of a 4-input remapping chip which will signi cantly expand capabilities and deliver multi-channel nulling as well as complex visibility data. The photonic nulling devices, inscribed within miniature, robust and environmentally stable monolithic chips are a promising avenue to one of astronomy's grandest challenges of characterising the chemical and physical environments of exoplanets

    Active production of large aspheric optics for astronomy

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    This thesis is devoted mainly to tackling the unsolved problem of producing secondary mirrors for 8 m telescopes, which will be up to 2-2.5 m in diameter and in excess of 1000 waves aspheric. This cannot be done by traditional methods. The project directly addresses the problem and forms part of the UK's R and D contributions to the Gemini USA/UK/Canada/Brazil/Chile/Argentina project to produce two 8 m telescopes. Its aim was to develop a new active method. The thesis starts with a review of astronomical implications of 8 m telescope projects currently being undertaken or planned worldwide and continues with discussions on technological challenges specifically in main optics production. The first stage of producing the mirror is generation of the aspheric surface profile by diamond milling. This has been directly addressed by developing a new computer-controlled profiler based on the existing manual hardware of the Grubb-Parsons 2.5 m machine. An essential part of the development also includes a computer controlled contact profilometer. The system performance is presented, including calibration, error profile and convergence of error compensation. The main part of the project was to develop polishing using a full size active lap, by which the pressure distribution and hence ablation rate are modulated in real time. The progress of the project is described, starting with a review of other approaches being developed world wide. The overall philosophy and design of active components are presented. Following this, experiments with a sub-diameter polisher and a prototype active lap of 85 cm in diameter, as built, are also described, including methods of testing, ablation algorithm and control theory. The final part of this section discusses the performance of the active polishing lap in terms of functionality at component and system levels. The conclusion briefly summarises the evaluation of the active method and its impact on large optics production. It also gives ideas for future improvements of performance, research work still needed and viable applications for the technique

    Exploring the NRO Opportunity for a Hubble-sized Wide-field Near-IR Space Telescope -- NEW WFIRST

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    We discuss scientific, technical and programmatic issues related to the use of an NRO 2.4m telescope for the WFIRST initiative of the 2010 Decadal Survey. We show that this implementation of WFIRST, which we call "NEW WFIRST," would achieve the goals of the NWNH Decadal Survey for the WFIRST core programs of Dark Energy and Microlensing Planet Finding, with the crucial benefit of deeper and/or wider near-IR surveys for GO science and a potentially Hubble-like Guest Observer program. NEW WFIRST could also include a coronagraphic imager for direct detection of dust disks and planets around neighboring stars, a high-priority science and technology precursor for future ambitious programs to image Earth-like planets around neighboring stars.Comment: 76 pages, 26 figures -- associated with the Princeton "New Telescope Meeting

    NASA Tech Briefs, January 2009

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    Tech Briefs are short announcements of innovations originating from research and development activities of the National Aeronautics and Space Administration. They emphasize information considered likely to be transferable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. Topics covered include: The Radio Frequency Health Node Wireless Sensor System; Effects of Temperature on Polymer/Carbon Chemical Sensors; Small CO2 Sensors Operate at Lower Temperature; Tele-Supervised Adaptive Ocean Sensor Fleet; Synthesis of Submillimeter Radiation for Spectroscopy; 100-GHz Phase Switch/Mixer Containing a Slot-Line Transition; Generating Ka-Band Signals Using an X-Band Vector Modulator; SiC Optically Modulated Field-Effect Transistor; Submillimeter-Wave Amplifier Module with Integrated Waveguide Transitions; Metrology System for a Large, Somewhat Flexible Telescope; Economical Implementation of a Filter Engine in an FPGA; Improved Joining of Metal Components to Composite Structures; Machined Titanium Heat-Pipe Wick Structure; Gadolinia-Doped Ceria Cathodes for Electrolysis of CO2; Utilizing Ocean Thermal Energy in a Submarine Robot; Fuel-Cell Power Systems Incorporating Mg-Based H2 Generators; Alternative OTEC Scheme for a Submarine Robot; Sensitive, Rapid Detection of Bacterial Spores; Adenosine Monophosphate-Based Detection of Bacterial Spores; Silicon Microleaks for Inlets of Mass Spectrometers; CGH Figure Testing of Aspherical Mirrors in Cold Vacuums; Series-Coupled Pairs of Silica Microresonators; Precise Stabilization of the Optical Frequency of WGMRs; Formation Flying of Components of a Large Space Telescope; Laser Metrology Heterodyne Phase-Locked Loop; Spatial Modulation Improves Performance in CTIS; High-Performance Algorithm for Solving the Diagnosis Problem; Truncation Depth Rule-of-Thumb for Convolutional Codes; Efficient Method for Optimizing Placement of Sensors
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