Vibrations of a shell with the discretely attached dynamic subsystem

A problem on low vibrations of a thin spherical shell is considered. A solid of finite dimensions is discretely attached to the shell by means of an elastic rod system. The calculation examples are presented.     

Confronting Observations and Modeling: The Role of the Interstellar Magnetic Field in Voyager 1 and 2 Asymmetries

Magnetic effects are ubiquitous and known to be crucial in space physics and astrophysical media. We have now the opportunity to probe these effects in the outer heliosphere with the two spacecraft Voyager 1 and 2. Voyager 1 crossed, in December 2004, the termination shock and is now in the heliosheath. On August 30, 2007 Voyager 2 crossed the termination shock, providing us for the first time in-situ measurements of the subsonic solar wind in the heliosheath. With the recent in-situ data from Voyager 1 and 2 the numerical models are forced to confront their models with observational data. Our recent results indicate that magnetic effects, in particular the interstellar magnetic field, are very important in the interaction between the solar system and the interstellar medium. We summarize here our recent work that shows that the interstellar magnetic field affects the symmetry of the heliosphere that can be detected by different measurements. We combined radio emission and energetic particle streaming measurements from Voyager 1 and 2 with extensive state-of-the art 3D MHD modeling, to constrain the direction of the local interstellar magnetic field. The orientation derived is a plane ～60°–90° from the galactic plane. This indicates that the field orientation differs from that of a larger scale interstellar magnetic field, thought to parallel the galactic plane. Although it may take 7–12 years for Voyager 2 to leave the heliosheath and enter the pristine interstellar medium, the subsonic flows are immediately sensitive to the shape of the heliopause. The flows measured by Voyager 2 in the heliosheath indicate that the heliopause is being distorted by local interstellar magnetic field with the same orientation as derived previously. As a result of the interstellar magnetic field the solar system is asymmetric being pushed in the southern direction. The presence of hydrogen atoms tend to symmetrize the solutions. We show that with a strong interstellar magnetic field with our most current model that includes hydrogen atoms, the asymmetries are recovered. It remains a challenge for future works with a more complete model, to explain all the observed asymmetries by V1 and V2. We comment on these results and implications of other factors not included in our present model.     

Measurement of mesopause temperature from hydroxyl nightglow at Kolhapur (16.8°N, 74.2°E), India

The paper reports the nightglow observations of hydroxyl (8–3), (7–2) and (6–2) Meinel band carried out at a low latitude station Kolhapur (16.8°N, 74.2°E, dip latitude 10.6°N), India during November 2002 to May 2005 with the objective of investigating mesopause dynamics based on derived OH rotational temperature. Overall, 132 nights of quality data were collected using filter-tilting photometer and an all-sky scanning photometer. The mean mesopause temperature observed at Kolhapur is 195 ± 11, 196 ± 9 and 195 ± 7 K from OH (8–3), (7–2) and (6–2) band emissions, respectively, using transition probabilities given by Langhoff et al. [Langhoff, S.R., Werner, H.J., Rosmus, P. Theoretical transition probabilities for the OH Meinel system. Journal of Molecular Spectroscopy 118, 507–529, 1986]. Small wave-like variations (periodicities ∼ few hours) existing over long period variations in derived temperatures are also present. A steady decrease of emission intensities from evening to dawn hours has been observed in approximately 59% of nights. No significant change of nightly mean temperatures has been noted. Furthermore, about 62% of observed nightly mean temperatures lie within one error bar of MSISE-90 model predictions.     

Evolution of galaxy cluster scaling from XMM-Newton observation of the galaxy clusters at z ⩾ 0.4

We present here new XMM-Newton observations of 3 relatively cool clusters at z ≈ 0.4, complemented by archival observations of 3 other clusters at similar redshift. We derived the M–T and R–T relations from the hydrostatic equation using an isothermal temperature distribution.     

The APT on the Polar Orbiting Weather Satellites

The receipt of the Pioneer Award has given me a chance to look back over my professional life and the opportunity to take stock of how I helped shape a small part of the world. While I hope this process entertains my contemporaries, more importantly, I hope it stimulates those that are engaged in actively shaping the present. To describe the need for automatic picture transmission (APT), I must retrace the historical development of meteorological satellites. The idea for weather observations from a satellite originated with a small group of meteorologists at the U.S. Army Signal Corps Research and Development Lab. at Ft. Monmouth, N.J., and resulted in the design of Vanguard II. The Tiros and TOS series of satellites, and the design of Nimbus, followed soon thereafter. However, a faster picture dissemination than was available at that time was needed, and it was this necessity that sparked the development of APT. Nimbus was originally intended to be an operational system, but the advent of simpler, less costly stabilization systems made the Tiros evolution the clear winner. The geosynchronous weather satellites started nearly a decade later and evolved from the NASA Application Technology Satellite (ATS) series. All three systems, existing polar orbiting weather satellites, APT, and geosynchronous weather satellites, have changed meteorology and the reliability of weather forecasting profoundly.     

Simultaneous measurement of multiple radiation-induced protein expression profiles using the Luminex(TM) system.

Space flight results in the exposure of astronauts to a mixed field of radiation composed of energetic particles of varying energies, and biological indicators of space radiation exposure provides a better understanding of the associated long-term health risks. Current methods of biodosimetry have employed the use of cytogenetic analysis for biodosimetry, and more recently the advent of technological progression has led to advanced research in the use of genomic and proteomic expression profiling to simultaneously assess biomarkers of radiation exposure. We describe here the technical advantages of the Luminex(TM) 100 system relative to traditional methods and its potential as a tool to simultaneously profile multiple proteins induced by ionizing radiation. The development of such a bioassay would provide more relevant post-translational dynamics of stress response and will impart important implications in the advancement of space and other radiation contact monitoring.     

On the structure and dynamics of the thermosphere

Thermospheric temperature, composition and wind measurements from the Dynamics Explorer satellite (DE-2) are interpreted using a three dimensional, multiconstituent spectral model. The analysis accounts for tides driven by the absorbed solar radiation as well as energy and momentum coupling involving the magnetosphere and lower atmosphere. We discuss phenomena associated with the annual tide, polar circulation, magnetic storms and substorms.     

The biological clock of Neurospora in a microgravity environment.

The circadian rhythm of conidiation in Neurospora crassa is thought to be an endogenously derived circadian oscillation; however, several investigators have suggested that circadian rhythms may, instead, be driven by some geophysical time cue(s). An experiment was conducted on space shuttle flight STS-9 in order to test this hypothesis; during the first 7-8 cycles in space, there were several minor alterations observed in the conidiation rhythm, including an increase in the period of the oscillation, an increase in the variability of the growth rate and a diminished rhythm amplitude, which eventually damped out in 25% of the flight tubes. On day seven of flight, the tubes were exposed to light while their growth fronts were marked. Some aspect of the marking process reinstated a robust rhythm in all the tubes which continued throughout the remainder of the flight. These results from the last 86 hours of flight demonstrated that the rhythm can persist in space. Since the aberrant rhythmicity occurred prior to the marking procedure, but not after, it was hypothesized that the damping on STS-9 may have resulted from the hypergravity pulse of launch. To test this hypothesis, we conducted investigations into the effects of altered gravitational forces on conidiation. Exposure to hypergravity (via centrifugation), simulated microgravity (via the use of a clinostat) and altered orientations (via alterations in the vector of a 1 g force) were used to examine the effects of gravity upon the circadian rhythm of conidiation.     

History of monopulse radar in the USSR

Monopulse radars have played an important role in air and missile defense systems since the development of the monopulse technique in the late 1940s. This paper outlines the application of monopulse radars in Russian defense systems, starting with the Moscow ABM system and continuing in instrumentation and air defense radars now widely deployed in Russia and elsewhere     

In situ measurements to determine if Phobos is layered

The complex system of linear features on Phobos—the inner moon of Mars—found by the Viking Orbiters in 1976, can be classified morphologically into three types according to their appearance as well as their geometrical distribution on the surface. One kind of grooves appears to form arcs of small circles normal to the Phobos-Mars direction. We propose that these grooves are the surface manifestation of layering within Phobos[4–6] which could have been formed when Phobos was a part of a much larger and geologically active parent planet.Here we suggest some measurements to observe whether Phobos has a layered structure or not. The suggestion contains remote sensing measurements (particularly determination of the magnetic field by magnetometer and by electron reflection method) by a spacecraft orbiting around Mars as well as surface measurements (active seismic reflection experiment) by a landing module on Phobos.