16 research outputs found
Gamma‐ray optical counterpart search experiment (GROCSE)
The requirements of a gamma‐ray burst optical counterpart detector are reviewed. By taking advantage of real‐time notification of bursts, new instruments can make sensitive searches while the gamma‐ray transient is still in progress. A wide field of view camera at Livermore National Laboratories has recently been adapted for detecting GRB optical counterparts to a limiting magnitude of 8. A more sensitive camera, capable of reaching mv=14, is under development. © 1994 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87629/2/633_1.pd
Autonomous, agile micro-satellites, and supporting technologies
This paper updates the on-going effort at Lawrence Livermore National Laboratory to develop autonomous, agile micro-satellites (MicroSats). The objective of this development effort is to develop MicroSats weighing only a few tens of kilograms, that are able to autonomously perform precision maneuvers and can be used telerobotically in a variety of mission modes. The required capabilities include satellite rendezvous, inspection, proximity-operations, docking, and servicing. The MicroSat carries an integrated proximity-operations sensor-suite incorporating advanced avionics. A new self-pressurizing propulsion system utilizing a miniaturized pump and non-toxic mono-propellant hydrogen peroxide was successfully tested. This system can provide a nominal 25 kg MicroSat with 200-300 m/s delta-v including a warm-gas attitude control system. The avionics is based on the latest PowerPC processor using a CompactPCI bus architecture, which is modular, high-performance and processor-independent. This leverages commercial-off-the-shelf (COTS) technologies and minimizes the effects of future changes in processors. The MicroSat software development environment uses the Vx-Works real-time operating system (RTOS) that provides a rapid development environment for integration of new software modules, allowing early integration and test. We will summarize results of recent integrated ground flight testing of our latest non-toxic pumped propulsion MicroSat testbed vehicle operated on our unique dynamic air-rail
Near-infrared camera for the Clementine mission
The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. The near-infrared (NIR) multi-spectral camera, one of two workhorse lunar mapping cameras (the other being the UV/visible camera), provided {approximately}200 in spatial resolution at 400 km periselene, and a 39 km across-track swath. This 1.9 kg infrared camera using a 256 x 256 InSb FPA viewed reflected solar illumination from the lunar surface and lunar horizon in the 1 to 3 {micro}m wavelength region, extending lunar imagery and mineralogy studies into the near infrared. A description of this light-weight, low power NIR camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights
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Cosmic Bombardment IV: Averting catastrophe in the here-and-now
At the present time, it is at least arguable that large-scale cosmic bombardment has been a major driver of the evolution of the terrestrialbiosphere. The fundamental motivation of the present paper is the (high) likelihood that the advent and rise of the human species hasn`t coincided with the cessation of soft and hard collisions in the Asteroid Belt or in the Oort Cloud, and that we will either stop the cosmic bombardment or it will eventually stop us. In the foregoing, briefly reviewed the prospects for active planetary defenses against cosmic bombardment in the very near-term, employing only technologies which exist now and could be brought-to-bear in a defensive system on a one-decade time-scale. We sketch various means and mechanisms from a physicist`s viewpoint by which such defensive systems might detect threat objects, launch interdiction machinery toward them and operate such machinery in their vicinity to alternately deflect, disperse or vaporize objects in the 0.1-10 km-diameter range, the ones whose size and population constitute the greatest threats to our biosphere. We conclude that active defenses of all types are readily feasible against 0.1 kmdiameter incoming cosmic bomblets and that even complete vaporization-class defenses are feasible against 1 km-diameter class objects of all compositions. When facing Great Extinctors of up to 10 km diameter, the feasible defensive methods depend upon the object`s size and composition. Dispersion defenses are feasible against all threat-classes, as are deflection approaches for bomblets up to {approximately} 10 km diameter; vaporization-level protection is, however, available only against dirty snowballs` of the {approximately} 1--2 km diameter class. Great Extinctors of sizes significantly greater than 10 km diameter challenge contemporary human technology ever more severely; fortunately, they appear to be rare on the several Aeon time-scales over which Sol will shift its spectral class
Evaluation of spray deposition in potatoes using various spray delivery systems
The tomato-potato psyllid incurs high control costs through intensive spraying and other treatments. A field study was conducted in March 2012 in Pukekohe, New Zealand, to evaluate the pesticide deposition potential of five different spray delivery systems. The treatments included a conventional boom, a canopy submerged drop sprayer combination, a pneumatic electrostatic spraying system, an air-assisted rotary atomizer, and a high-volume air-assist boom. Each system was calibrated for appropriate spray volume rates between 167 and 400 litres/ha. Rhodamine WT fluorescent dye used as a tracer was sampled on folded Kromekote® sampling cards oriented flat and horizontally above, central to, and below the canopy. Spray coverage rates were quantified at designated heights adjacent to leaves to assess deposition throughout the potato canopy. All treatments that consisted of one or more novel technologies consistently gave higher coverage to the underside of the potato leaves than with the conventional boom
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Genius Sand: A Miniature Kill Vehicle Technology to Support Boost Phase Intercepts and Midcourse Engagements
This paper summarizes Lawrence Livermore National Laboratory's (LLNL) approach to a proposed Technology Demonstration program for the development of a new class of miniature kill vehicles (MKVs), that they have termed Genius Sand (GS). These miniaturized kinetic kill vehicles offer new capabilities for boost phase intercept (BPI) missions, as well as midcourse intercepts and the defeat of advanced countermeasures. The specific GS MKV properties will depend on the choice of mission application and system architecture, as well as the level of coordinated or autonomous operations in these missions. In general the GS MKVs will mass from between 1 to 5 kilograms and have several hundred meters per second of {Delta}v and be capable of several g's of acceleration. Based on the results of their previous study effort, they believe that it is feasible to develop and integrate the required technologies into a fully functional GS MKV prototype within the scope of a three-year development effort. They will discuss some of the system architecture trades and applicable technologies that can be applied in an operational MKV system, as a guide to focus any technology demonstration program. They will present the results of a preliminary 6DOF analysis to determine the minimum capabilities of an MKV system. They also will discuss a preliminary design configuration of a 2 kg GS MKV that has between 300-500 m/s of {Delta}v and has at least 2-g's of acceleration capability. They believe a successful GS MKV development effort will require not only a comprehensive component miniaturization program, but a rapid hardware prototyping process, and the ability to utilize high fidelity ground testing methodologies
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Gamma-ray optical counterpart search experiment (GROCSE)
The requirements of a gamma-ray burst optical counterpart detector are reviewed. By taking advantage of real-time notification of bursts, new instruments can make sensitive searches while the gamma-ray transient is still in progress. A wide field of view camera at Livermore National Laboratories has recently been adapted for detecting GRB optical counterparts to a limiting magnitude of 8. A more sensitive camera, capable of reaching m{sub upsilon} = 14, is under development
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Experiment to study the. beta. -decay of free atomic and molecular tritium. [For determining antineutrino mass]
An apparatus is described which will allow the measurement of the ..beta..-decay of free tritium atoms and molecules for determining antineutrino mass. It consists of an RF dissociator, a long cylindrical decay region open at both ends, a guide field, and a magnetic spectrometer