Cross Sections and Reaction Rates for Comparative Planetary Aeronomy

In this chapter we describe the current knowledge of a selection of collision processes and chemical reactions of importance to planetary aeronomy. Emphasis is placed on critical evaluation of what we know and what we wish we knew about fundamental processes required for interpretation, explanation, and modeling of atmospheric observations.     

High resolution X-ray spectroscopy and chemical evolution in elliptical galaxies

We discuss the elemental composition in the hot ISM of elliptical galaxies derived from new and recent X-ray spectral analysis in the context of new phenomenological models of their chemical evolution. Star formation histories, the IMF, the astrophysics of supernovae, and the nature of galactic winds impact the metal content and relative abundances in the hot ISM. We evaluate how X-ray spectroscopy may be utilized to deconstruct how elliptical galaxies, and the stellar populations that compose them, form and evolve, with an emphasis on present and future high resolution spectroscopic analysis.     

The New Horizons Spacecraft

The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments designated by the science team to collect and return data from Pluto in 2015. The design meets the requirements established by the National Aeronautics and Space Administration (NASA) Announcement of Opportunity AO-OSS-01. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration consistent with meeting the AO requirement of returning data prior to the year 2020. The spacecraft subsystems were designed to meet tight resource allocations (mass and power) yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto fly-by is 4.5 hours. Missions to the outer regions of the solar system (where the solar irradiance is 1/1000 of the level near the Earth) require a radioisotope thermoelectric generator (RTG) to supply electrical power. One RTG was available for use by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on approximately 200 W. The travel time to Pluto put additional demands on system reliability. Only after a flight time of approximately 10 years would the desired data be collected and returned to Earth. This represents the longest flight duration prior to the return of primary science data for any mission by NASA. The spacecraft system architecture provides sufficient redundancy to meet this requirement with a probability of mission success of greater than 0.85. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial in-flight tests have verified that the spacecraft will meet the design requirements.     

The Allen telescope array: Commensal and efficient SETI

The Allen telescope array (ATA) currently under construction affords the possibility of a dedicated and highly efficient SETI program that may be done commensally with other radio astronomy programs. This symbiosis is important in order to maintain and sustain the long-term effort that may be required in order to achieve success as a positive or null result. The technology that is being exploited is the construction of many small elements that allow large fields-of-view at high sensitivity, the use of ultra-wideband front-ends, and the use of flexible digital “intermediate frequency (IF)” systems. The project is under construction in phases, with the first 32 antennas expected to be functional in the fall of 2004, the next 173 dishes operational early 2006, with plans for 350 antennas total within this decade.     

Astronaut photography and the intelligence community: Who saw what?

Despite NASA's astronaut photography benefiting a wide range of civilian interests, it occasionally conflicted directly with the critical national security requirement to protect the National Reconnaissance Program from public disclosure or compromise. The Intelligence Community consequently imposed a number of restrictions, from reviewing the photography before public release to limiting the capabilities of NASA's image-forming sensors. At the same time, beginning in the Mercury program the Intelligence Community acquired and analyzed some of the photography as a possible source of intelligence data that otherwise was not being collected.     

Is high resolution possible aboard minisatellites?

To achieve the size reductions needed to lower the costs of space imaging, every part of a satellite (telescope, detector, digitization, image compression, memory, telemetry, and of course satellite platform) has to be improved. With regard to the instrument, new dimensioning rules, new optical designs, and new detection systems allow significant gains. Better balance between detector and optics modulation transfer function (MTF) performances can be achieved. Though the involved solutions raise the question of signal level, the latter can be solved with the use of TDI (Time Delay and Integration) detection. The instrumental choices, the optical system under investigation and how the above techniques are allowed for in the next generation SPOT satellites development studies led by CNES will be presented in this paper, showing how they can achieve the goal of weight reductions.     

Effects of several environmental factors on sweetpotato growth.

Effects of relative humidity, light intensity and photoperiod on growth of 'Ga Jet' and 'TI-155' sweetpotato cultivars, using the nutrient film technique (NFT), have been reported. In this study, the effect of ambient temperature regimes (constant 28 degrees C and diurnal 28:22 degrees C day:night) and different CO2 levels (ambient, 400, 1000 and 10000 microliters/L--400, 1000 and 10000 ppm) on growth of one or both of these cultivars in NFT are reported. For a 24-h photoperiod, no storage roots were produced for either cultivar in NFT when sweetpotato plants were grown at a constant temperature of 28 degrees C. For the same photoperiod, when a 28:22 degrees C diurnal temperature variation was used, there were still no storage roots for 'TI-155' but the cv. 'Ga Jet' produced 537 g/plant of storage roots. For both a 12-h and 24-h photoperiod, 'Ga Jet' storage root fresh and dry weight tended to be higher with a 28:22 degrees C diurnal temperature variation than with a constant 28 degrees C temperature regime. Preliminary results with both 'Ga Jet' and 'TI 155' cultivars indicate a distinctive diurnal stomatal response for sweetpotato grown in NFT under an ambient CO2 level. The stomatal conductance values observed for 'Ga Jet' at elevated CO2 levels indicated that the difference between the light- and dark-period conductance rates persisted at 400, 1000, and 10000 microliters/L.     

Deployment Mechanisms on the Fast Satellite: Magnetometer,Radial Wire,and Axial Booms

The Fast Auroral SnapshoT (FAST) satellite was launched by a Pegasus XL on August 21, 1996. This was the second launch in the NASA SMall EXplorer (SMEX) program. Early in the mission planning the decision was made to have the University of California at Berkeley Space Sciences Laboratory (UCB-SSL) mechanical engineering staff provide all of the spacecraft appendages, in order to meet the short development schedule, and to insure compatibility. This paper describes the design development, testing and on-orbit deployment of these boom systems: the 2 m carbon fiber magnetometer booms, the 58 m tip to tip spin-plane wire booms, and the 7 m dipole axial stiff booms.