We present experimental results showing that basalt is oxidized in gas mixtures with CO number densities approximately equal to those at the surface of Venus. Although the gas mixtures have CO/CO2 ...ratios falling inside the magnetite stability field, Mössbauer spectroscopy shows that hematite and Fe3+ in pyroxene are produced in the oxidized basalt. The results suggest that the red color observed at several Venera landing sites is due to sub-aerial oxidation of Fe2+-bearing basalt on the surface of Venus, and that hematite, instead of magnetite, is present on the surface of Venus.
NEAR multispectral imaging was obtained at seven wavelengths (450–1050 nm) to characterize hemispheric and regional color properties of Eros. The highest-resolution whole-disk data, 180 m/pixel, were ...obtained during the last pre-orbit insertion sequence on 12 February 2000. The same areas were imaged again in color at 10–20 m/pixel from high orbit in March–April 2000, and selected targets have been studied in color at resolutions as high as 4 m/pixel from low orbit. Whole-disk spectra are in close agreement with ground-based observations. These and the disk-resolved measurements show little variation in visible-wavelength color, but they do reveal spatial variation of several percent in the 950-nm/760-nm reflectance ratio, used here as a proxy for depth of the 1-μm olivine-pyroxene absorption band. After photometric correction to i=30° e=0° using both a Hapke correction and a modified empirical phase function, the disk-resolved images show reproducible spatial variations in albedo and 950-nm/760-nm reflectance ratio. The northern hemisphere exhibits average reflectances at i=30°, e=0° of 0.136±0.007 at 760 nm and 0.115±0.006 at 950 nm, equivalent to geometric albedos of 0.30±0.02 and 0.26±0.02, respectively. There is more than factor of 2 spatial variation in reflectance, but only about 10% variation in the 950-nm/760-nm reflectance ratio. Reflectance and color ratio are highly correlated, with the highest reflectances in discrete, sharp-edged patches on slopes exceeding 20°, consistent with material being exposed by downslope movement. Eros is also conspicuously deficient in small, bright, spectrally distinctive craters which are found on the other two S asteroids, Gaspra and Ida, imaged by spacecraft at close range. Eros exhibits a larger range of albedos than other S asteroids, but its color variations are much more subtle: variation in the 950-nm/760-nm reflectance ratio with 760-nm reflectance is several times less than on those asteroids or in the lunar maria. Of the different mechanisms possibly responsible for reflectance and color differences on Eros, spatial differences in the extent of regolith aging by space weathering are most consistent with Eros's observed properties. However, the effects of this process are both qualitatively and quantitatively different than in the lunar maria.
The previous four articles in this series on the Web, Communication Trends, and Children's Health (Clinical Pediatrics, March-June, 1998) have shown that the Internet is a rich interactive window on ...the world, with health-related resources not readily available elsewhere. While the Internet brings great benefits, there are also some significant potential drawbacks. In this final article of the series, we focus on the precautions parents, teachers, and caregivers can take to help children and their families use the Internet wisely and safely.
The CONTOUR remote imager and spectrograph Fort, D.; Warren, J.; Strohbehn, K. ...
Acta astronautica,
2003, 2003-1-00, 20030101, Letnik:
52, Številka:
2
Journal Article
Recenzirano
The Comet Nucleus Tour (CONTOUR) is a NASA Discovery mission to study the diversity of comet nuclei. Top level mission goals include imaging the nuclei of several comets at resolutions up to
4
m/
...pixel
, acquiring spectral information in both the visible and infrared (IR), and obtaining detailed compositional measurements of the gas and dust. The CONTOUR Remote Imager and Spectrograph (CRISP) instrument, under development at The Johns Hopkins University Applied Physics Laboratory, achieves the primary imaging and spectral mapping objectives. CRISP includes a visible imager and 10-position filter wheel to survey the visible spectrum from 400 to
800
nm
and provide high-resolution images of the nucleus. An imaging spectrograph, utilizing a
256×256
HgCdTe
array and yielding a spectral resolution of
7
nm
, analyzes the infrared IR spectrum from 800 to
2500
nm
. A Stirling cycle refrigerator cools the IR array to cryogenic operating temperatures. The imager and spectrograph share a common optical path that includes a scan mirror to actively track the comet nucleus during approach and fly-by. An overview of the CRISP instrument is presented.
The historical background of the existential critique of psychoanalysis was the attack against positivism mounted toward the end of the nineteenth century. The link is to be found in the early ...writings of Ludwig Binswanger, the Swiss psychiatrist who introduced the idea of existential analysis. The works of his pre-existentialist period were concerned with the theoretical and methodological issues involved in the debate about the nature of the human sciences that preoccupied continental philosophy in the decades before the First World War. Indeed, Binswanger is an interesting figure in twentieth-century intellectual history not only for his own contributions but because
Existentialism, it was argued in chapter four, completed the critique of rationalism begun before World War I by offering a theory of motivation that accounted for the human desire to escape from ...freedom. This did not put the existentialists into the camp of the irrationalists, however; on the contrary, they insisted on the inescapable reality of human responsibility for human choices and used their theory of motivation to explain the ideological belief systems and everyday self-deceptions by which men tried to escape it. However, the existentialists did not fully appreciate the negative implications of their own conclusions.
In rejecting the
INTRODUCTION Izenberg, Gerald N
The Existentialist Critique of Freud: The Crisis of Autonomy,
03/2015
Book Chapter
This book is a study of the critique of Freud’s theories advanced by a number of existential philosophers and psychiatrists. On one level, it is necessarily concerned with philosophical psychology, ...for the existentialists saw themselves in relation to Freud primarily as opponents of what they regarded as the humanistically inappropriate and conceptually unsound structure of explanation in psychoanalytic theory. On another level, however, it is the history of a stage in the crisis of the European rationalist tradition. Behind the methodological issues raised by the existentialists was a conception of the self that ran counter to the one that had
In the last chapter it was argued that the existential critique of Freud could not be adequately characterized as a philosophical debate about the proper foundations of a science of human behavior. ...The attacks on mechanism and biologism, which were explored in detail in chapter three, were part of a more fundamental difference with Freud about the nature of human motivation and selfhood. This difference emerged in the historical setting of crumbling faith in the premises of European rationalism. If Heidegger laid the foundations for the new view of human motivation, however, it was left to others to apply it
Psychoanalysis, it was argued in chapter four, represented the internalization of rationalist social theory and its central problem. In the guise of biological instincts, the conflict between ...individual interest (autonomy) and social harmony was fought out on the level of the individual rather than on that of society. The same difficulties of reconciliation that in social theory were manifest as interpersonal conflict and social and political disequilibrium were manifest within the personality as internal conflict and symptom formation.
At this point, however, it is necessary to make distinctions within rationalist social theory that were initially glossed over in the emphasis
