Pressure and Ionization Balances in the Circum-Heliospheric Interstellar Medium and the Local Bubble

A disconcerting mismatch of thermal pressures for two media in contact with each other, (1) the warm, Circum-Heliospheric Interstellar Medium (CHISM) and (2) the very hot material within a much larger region called the Local Bubble (LB), has troubled astronomers for over two decades. A possible resolution of this problem, at least in part, now seems possible. We now understand that earlier estimates for the average electron density in the very hot LB plasma were inflated by an unrecognized foreground contamination to the low energy diffuse X-ray background measurements. This foreground illumination arises from photons emitted by charge exchange reactions between solar wind ions and neutral atoms from the interstellar medium that enter into the heliosphere. However, with the resolution of this problem comes a new one. The high ionization fraction of helium in the CHISM, relative to that of hydrogen, could be understood in terms of the effects from a strong flux of EUV and X-ray radiation coming from both the Local Bubble and a conductive interface around the CHISM. A revision of this interpretation may now be in order, now that the photoionization rate from radiation emitted by hot gas the Local Bubble is lower than previously assumed.     

Effect of bacterial population density on germination wheat seeds and dynamics of simple artificial ecosystems.

Effect of the size of rhizospheric bacterial populations on germination of seeds and development of simple terrestrial "wheat plants--rhizospheric microorganisms--artificial soil" and "wheat plants-artificial soil" systems has been studied. Experiments demonstrated that within specify ranges in the inoculate, the rhizospheric bacteria are capable of increasing the yield of germinated seeds and stimulate the growth of plantlets. Germination of seeds inoculated with bacteria was either stimulated, or inhibited or remained at control levels depending on the amount of bacteria. Plant biomass growth and total photoassimilation has been found to depend on the amount of bacteria on the plant roots: the higher the amount of bacteria on plant roots, the smaller is the biomass of plants but the total photoassimilation is, higher. Thus, depending on the amount of bacteria on the roots of plants the system either increases the biomass of plants or increases the total photoassimilation, i.e. "pumps" carbon through itself involving bacteria. Grant numbers: N99-04-96017, N15.     

EUVITA — An extreme UV imaging telescope array with spectral capability

EUVITA is a set of 8 extreme UV normal incidence imaging telescopes, each of them sensitive in a narrow band (λ/Δλ = 15 to 80), centered at wavelengths between 50 and 175 Å. Each telescope has an effective area of a few cm²; a field of view of 1.2° and a spatial resolution of 10 arcsec.

EUVITA will be flown on the Russian mission SPECTRUM X-G. This satellite will be launched in a highly eccentric orbit with a period of 4 days, allowing long, uninterrupted observations (e.g. 10⁵ seconds). EUVITA's narrow spectral bands allow the measurement of source parameters such as temperature or power law index as well as interstellar absorption, and will resolve groups of strong lines emitted by optically thin hot plasmas.     

Accessing NASA technology with the World Wide Web

NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer and technology awareness applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology Opportunities Showcase (TOPS), an industrial partnering showcase that exists on the Web long after the actual 3-day event ended. The NASA Technical Report Server (NTRS) provides uniform access to many logically similar, yet physically distributed NASA report servers. WWW is also the foundation of the Langley Software Server (LSS), an experimental software distribution system which will distribute LaRC-developed software. In addition to the more formal technology distribution projects, WWW has been successful in connecting people with technologies and people with other people     

Experiments with injection of powerful plasma jet into the ionosphere

This paper describes two rocket experiments “Aelita” with high power lithium plasma injection. The results of onboard magnetometer, massspectrometer, photometer, plasma, corpuscular and ground radar measurements are given. Dynamics and structure of plasma formation are discussed.     

Improvement of Automatic Landing Through the Use of a Space Diversity ILS Receiving System

A space diversity method of receiving and processing ILS localizer information has been developed and flight tested. Multiple lateral ly separated antennas are used which sense the ILS signal on and around the approach path. Combining these signals suppresses ILS beam distortion produced by multipath signal interference and provides much improved guidance information to the landing aircraft control system.     

The uses of past and present magnetospheric field models for mapping fluxes and calculating conjugate points

Two different utilisations of magnetospheric models are described in this paper. In the first one very crude analytical expressions are used to describe the motion of energetic particles and the evolution of fluxes along a given orbit. In the second one, the exact internal and external fields are used for field line tracing and the determination of conjugate points. Applications to the calculation of synchronous fluxes and the Geos conjugate points are given.     

The optical parameters of the atmosphere of Venus

This work is devoted to the derivation of the optical properties of the Venus atmosphere from “Venera-10” optical measurements. Within the framework of a two-layer model of Venus atmosphere it is found that in the spectral interval 0.52 – 0.85 μm the optical thickness of the upper cloud layer is ≈ 50 and the optical parameters of the lower layer are similar to the Rayleigh ones. Comparison is made between the measurements of radiation field within the atmosphere and the results of strict calculations. A preliminary conclusion is suggested that there are considerable numbers of aerosol particles with a radius ? 0.03 μm in the lower layer. The results of the upper boundary of the cloud layer is estimated to be ≈ 70 km.