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Ukraine has launch vehicles that are able to deliver about 300 kg to lunar orbit. A future Ukrainian lunar program may propose a polar orbiter. This orbiter should fill principal information gaps in our knowledge about the Moon after the Clementine and Lunar Prospector missions and future missions like Smart-1, Lunar-A, and Selene. We consider that this can be provided by radar studies of the Moon with supporting optical photopolarimetric observations from lunar polar orbit. These experiments allow one to better understand global structure of the lunar surface at a wide range of scales, from microns to kilometers. We propose three instruments for the prospective lunar orbiter. They are a synthetic aperture imaging radar, ground-penetrating radar, and imaging UV-spectropolarimeter. The main purpose of the synthetic aperture imaging radar experiment is to study with high-resolution (50 m) permanently shadowed sites in the lunar polar regions. These sites are cold traps for volatiles, and have a potential for resource utilization. Possible presence of water ice in the regolith in the sites makes them interesting for long-term manned bases on the Moon. Radar and optical imaging and mapping of other interesting regions could be also planned. Multi-frequency, multi-polarization sounding of the lunar surface with ground-penetrating radar can provide data about internal structure of the lunar surface from meters to several hundred meters deep. The ground-penetrating radar can be used for measuring megaregolith properties, detection of cryptomaria, and studies of internal structure of the largest craters. Modest spatial resolution (50 m) of the imaging UV-spectropolarimeter should provide total coverage (or coverage of a large portion) of the lunar surface in oblique viewing at large phase angles. Polarization degree at large (>90°) phase angles bears information about characteristic size of the regolith particles. Additional experiments could use the synthetic aperture imaging radar system, e.g., bistatic radar sounding with the on-board transmitter and Earth-based receiver, and interferometry with the on-board transmitter and two Earth-based receiving antennas that allows reconstruction of the surface topography with high resolution.

Twenty precise compact DC voltages sources based on 6.4-V Zener diodes have been manufactured and investigated by the NPO VNIIFTRI measuring system during the year. Eight sources with voltage drift of less than 8 ppm/year and different drift signs as well as with noise levels lower than 100 nV in the 0.01-10 Hz frequency band have been selected. These sources were used for manufacturing two four-channel reference standards. One standard has been investigated by the Russian 1-V Josephson systems, and another one was examined at the NPO VNIIFTRI. The output voltage drift of the standard sources both under laboratory conditions and during transportation exhibits a linear time dependence. The spread of experimental points with respect to a linear extrapolation did not exceed 2/spl middot/10/sup -7/. The drift value of the best channel was less 0.5 ppm/year. >

A set of instruments for reproduction and storage of the emf and dc voltage unit and for transferring it directly to the location where measuring instruments (MIs) are used with an accuracy of (3–5) ·10−7, developed at the “VNIIFTRI” Research and Production Association (RPA) is described. The metrological characteristics of the set are investigated.

Contemporary methods of investigation of bipolar outflows are based on the spectral line analysis of molecule rotational transitions. Usually, the 12CO is used. Calculations involve assumption of local thermodynamic equilibrium. It is also assumed that optical depth of the analyzed lines should be less than 1. In the core of the 12CO molecule line profile the optical depth is much more than 1, that is why only line wings can be analyzed. This approach gives a possibility to consider high-velocity parts of bipolar outflow only.

In this paper, a low-noise pHEMT amplifier with an extra-low supply (0.25 V, 2 mA) is presented. The two-stage amplifier, based on low-cost commercially available components, has a noise figure of about 1 dB and gain of 20 /spl plusmn/ 1 dB over the 1.5 to 2.5 GHz. The input/output return loss do not exceed -5/- 8 dB, thermal gain variation is of 0.05 dB//spl deg/C. Via comparison with state of-the-art low-power low-noise amplifiers, it is confirmed that pHEMT has a grate potential as active element for extra-low DC-power-consumption microwave amplifiers.

The magnetic and optical properties of two types of hole centers formed in KDP (KH/sub 2/PO/sub 4/) under irradiation and variation of their concentration at thermal, laser and radiation annealing of crystals have been investigated by means of ESR and optical spectroscopy methods. It has been found that wide bands of optical absorption in the UV region of the spectrum with the maximum near 268 nm belong to these centers.

The investigation carried out on the industrial crystals and analysis of the works of the different authors show that any choice of one or another method for the improvement of the qualities of the KH/sub 2/PO/sub 4/ (KDP) and KD/sub 2/PO/sub 4/ (DKDP) crystals depends on the specific application of the crystals and the types of defects in the crystals. The thermal conditioning can be effectively used for recovering optical transparency of gamma, X-ray, or UV irradiated crystals. The thermal and laser conditioning methods improving laser damage threshold are effective for the crystals used for the frequency, conversion of the high-intensive laser radiation. It is necessary to use the ionizing radiation conditioning method for the crystals worked.. at the ionizing irradiation conditions.

Ultra-low-noise amplifiers, having noise temperature 10-20 K under moderate (uncryogenic) cooling, for the ranges 0.5-1, 1-2, 2-4 GHz are presented. The design peculiarities aimed to the most effective realization of modern PHEMTs potential are described. Relying on obtained experimental data prediction, it is drown that noise temperature of uncooled broadband amplifiers may be reduced down to 10 K over 0.3 to 3 GHz band.

Five transportable Zener-diode dc voltage standards have been developed, fabricated and investigated at the NPO VNIIFTRI. The standards were designed to transfer the unit of electromotive force (emf) from Josephson reference standards to measuring instruments. Following the results of these investigations, standard N 02 has been used for intercomparison of the Russian Josephson reference standards.

The processes of active star formation in interstellar molecular clouds lead molecules to a nonequilibrium distribution throughout the available energy levels. This is the reason why molecular clouds are sources of fairly intense radiation, with the frequency spectrum determined by vibratory-rotational levels of the energy structure of the molecules. It is known that in star formation regions molecules such as H/sub 2/O, OH, SiO and some others may be in an inversion state. Calculations have shown that under certain conditions in molecular clouds, the CO molecule inversion may also exist in the J=1-0 transition.

The possibility is shown of using transportable solid- state voltage measures for the transfer of emf and dc voltage units in the highest link of the GOST 8.027- 89 calibration scheme with an error (5–6)·10−7.