The solar orbiter mission

Approved in October 2000 by ESA's Science Programme Committee as a flexi-mission, the Solar Orbiter will studythe Sun and unexplored regions of the inner heliosphere from a unique orbit that brings the probe to within 45 solar radii (0.21 AU) of our star, and to solar latitudes as high as 38°. This orbit will allow the Solar Orbiter to make fundamental contributions to our understanding of the acceleration and propagation of energetic particles in the extended solar atmosphere. During quasi-heliosynchronous phases of the orbit, Solar Orbiter will track a given region of the solar surface for several days, making possible unprecedented studies of the sources of impulsive and CME-related particle events. The scientific payload to be carried by the probe will include a sophisticated remote-sensing package, as well as state-of-the-art in-situ instruments. The multi-wavelength, multi-disciplinary approach of Solar Orbiter, combined with its novel location, represents a powerful tool for studies of energetic particle phenomena.     

Effects observed in the equatorial and low latitude ionospheric F-region in the Brazilian sector during low solar activity geomagnetic storms and comparison with the COSMIC measurements

The main objective of the present investigation has been to compare the ionospheric parameters (NmF2 and hmF2) observed by two ground-based ionospheric sounders (one at PALMAS- located near the magnetic equator and the other at Sao Jose dos Campos-located in the low-latitude region) in the Brazilian sector with that by the satellite FORMOSAT-3/COSMIC radio occultation (RO) measurements during two geomagnetic storms which occurred in December 2006 and July 2009. It should be pointed out that in spite of increasing the latitude (to 10°) and longitude (to 20°) around the stations; we had very few common observations. It has been observed that both the peak electron density (NmF2) and peak height (hmF2) observed by two different techniques (space-borne COSMIC and ground-based ionosondes) during both the geomagnetic storm events compares fairly well (with high correlation coefficients) at the two stations in the Brazilian sector. It should be pointed out that due to equatorial spread F (ESF) in the first storm (December 2006) and no-reflections from the ionosphere during nighttime in the second storm (July 2009), we had virtually daytime data from the two ionosondes.     

Future test system architectures

An expanding number of test system architectural choices has caused confusion in the test engineering community. This will show the strengths and weaknesses of existing test system architectures including rack and stack systems with GPIB instruments and modular systems like VXI and PXI. It will provide a glimpse into an emerging new architecture: LAN-based test systems. The paper reviews key concerns such as costs, channel counts, footprints, IO speeds, ease-of-integration, and flexibility. The objective of the paper is to provide engineers insight into the most effective test systems for their future applications.     

Submillimeter spectroscopy from space — Missions planned between 1995 and 2005

The submillimeter wavelength range (100 μm ≤ λ ≤ 1 mm) is exceptionally rich in atomic and molecular transitions that provide direct measures of the chemical composition, temperature, density, and cooling of the interstellar medium. In part, this is due to the fact that the most abundant oxygen- and carbon-bearing species as well as the most common hydrides have their lowest lying transitions within this wavelength region. However, because of the great abundance of many of these same species in our own atmosphere (e.g., H₂O and O₂), terrestrial absorption at submillimeter wavelengths is strong, rendering much of the sky inaccessible to ground- and even airborne observing platforms. In recognition of the scientific importance of the submillimeter range to astronomy and the limitations placed on its pursuit by the atmosphere, both NASA and ESA have embarked on ambitious programs to explore these wavelengths from space.     

A database for crew system design: lessons-learned

To aid designers in overcoming problems of technical oversights or designer unfamiliarity with the operational environment, a database of lessons learned has been specified to highlight previously identified design deficiencies and prevent their perpetuation. Interface design requirements, search and retrieval procedures, and special system features are described, and a user interface is proposed for such a system. The content and organization of the lessons learned and a form to guide contributors through performance of new lessons are presented     

Physical events in the track structure of heavy ions and their relation to alterations of biomolecules.

Heavy charged particles interacting with biological cells can produce a wide variety of different physical, chemical and biological consequences. A rigorous identification of relevant chemical and biological alterations of biomolecules in cells, however, is still lacking and, thus, it is difficult to identify the potential biological importance of different early physical events. In addition, due to experimental and theoretical problems also little is known about the details of energy transfer, -absorption and -decay from projectiles to atoms/molecules in condensed targets; this is particularly true for not completely stripped heavy ions. Nevertheless, one might conclude from available data that higher densities of physical energy absorption events have a significantly higher probability to lead to qualitatively more severe biochemical alterations as regards the induction of DNA double strand breaks and of chromatin damage. It is not very likely that energy migration along the DNA molecule in biological cells over long distances plays a significant role as contributor to these biological radiation effects.     

Early martian environments: the Antarctic and other terrestrial analogs.

The comparability of the early environments of Mars and Earth, and the biological evolution which occurred on early earth, motivates serious consideration of the possibility of an early martian biota. Environments which could have contained this early martian life and which may presently contain evidence of this former life include aquatic, ice, soil, and rock habitats. Several analogs of these potential early martian environments, which can provide useful information in searching for extinct life on Mars, are currently available for study on Earth. These terrestrial analogs include the perennially ice-covered lakes and sandstone rocks in the Polar Deserts of Antarctica, surface of snowfields and glaciers, desert soils, geothermal springs, and deep subsurface environments.