Book reviews

Space Science Reviews -     

Radar: The Cassini Titan Radar Mapper

The Cassini RADAR instrument is a multimode 13.8 GHz multiple-beam sensor that can operate as a synthetic-aperture radar (SAR) imager, altimeter, scatterometer, and radiometer. The principal objective of the RADAR is to map the surface of Titan. This will be done in the imaging, scatterometer, and radiometer modes. The RADAR altimeter data will provide information on relative elevations in selected areas. Surfaces of the Saturn’s icy satellites will be explored utilizing the RADAR radiometer and scatterometer modes. Saturn’s atmosphere and rings will be probed in the radiometer mode only. The instrument is a joint development by JPL/NASA and ASI. The RADAR design features significant autonomy and data compression capabilities. It is expected that the instrument will detect surfaces with backscatter coefficient as low as −40 dB.RADAR Team LeaderThis revised version was published online in July 2005 with a corrected cover date.     

The Galactic Environment of the Sun: Interstellar Material Inside and Outside of the Heliosphere

Interstellar material (ISMa) is observed both inside and outside of the heliosphere. Relating these diverse sets of ISMa data provides a richer understanding of both the interstellar medium and the heliosphere. The galactic environment of the Sun is dominated by warm, low-density, partially ionized interstellar material consisting of atoms and dust grains. The properties of the heliosphere are dependent on the pressure, composition, radiation field, ionization, and magnetic field of ambient ISMa. The very low-density interior of the Local Bubble, combined with an expanding superbubble shell associated with star formation in the Scorpius-Centaurus Association, dominate the properties of the local interstellar medium (LISM). Once the heliosphere boundaries and interaction mechanisms are understood, interstellar gas, dust, pickup ions, and anomalous cosmic rays inside of the heliosphere can be directly compared to ISMa outside of the heliosphere. Our understanding of ISMa at the Sun is further enriched when the circumheliospheric interstellar material is compared to observations of other nearby ISMa and the overall context of our galactic environment. The IBEX mission will map the interaction region between the heliosphere and ISMa, and improve the accuracy of comparisons between ISMa inside and outside the heliosphere.     

The plasma physics of shock acceleration

The notion that plasma shocks in astrophysical settings can and do accelerate charged particles to high energies is not a new one. However, in recent years considerable progress has been achieved in understanding the role particle acceleration plays both in astrophysics and in the shock process itself. In this paper we briefly review the history and theory of shock acceleration, paying particular attention to theories of parallel shocks which include the backreaction of accelerated particles on the shock structure. We discuss in detail the work that computer simulations, both plasma and Monte Carlo, are playing in revealing how thermal ions interact with shocks and how particle acceleration appears to be an inevitable and necessary part of the basic plasma physics that governs collisionless shocks. We briefly describe some of the outstanding problems that still confront theorists and observers in this field.     

Gender differences in leader and follower perceptions of social support in Antarctica

The purpose of this study was to methodologically explore the links among social support, gender, age, prior experience, leader/follower status, and leadership effectiveness noted in previous accounts from Antarctic stations. Data for this study were collected from volunteers involved in Australian National Antarctic Research Expeditions conducted from 1996 to 2001. Multilevel analysis revealed that most of the variance in perceptions of social support was at the individual level (71%). Perceptions of social support had less variance at the group level (29%) and little variance at the weekly level. At the group level, the explanatory variables we examined included leadership effectiveness, gender similarity, and age similarity. At the individual level, the explanatory variables we examined included age, gender, prior experience, and leader/follower status. An interaction between gender and leader/follower status contributed to a significant model of variation in perceptions of social support.     

Accretion disks in stellar X-ray sources

This review presents an introduction to the theory of accretion disks. After explaining the importance of accretion disks in stellar X-ray sources, it considers observational and theoretical indications of the formation of accretion disks in close binary systems. The simple Shakura and Sunyaev model and its problems are discussed. A survey of other models that try to improve upon this model is given (in Table III), and critically discussed.     

Modular ICNIA Packaging Technology

Significant size, weight, power and reliability improvements can be achieved in next generation avionics by the modular integration of similar functions into a fault tolerant reconfigurable architecture. The Integrated Communication Navigation Identification Avionics program (ICNIA), and ITT/TI Joint Venture, is accomplishing this task with a combination of modular circuit designs using VHSIC technology, improved packaging designs incorporating surface mount component technology and a modular two-level maintenance support concept for reduced life cycle cost. This article will concentrate on the modular packaging technology of the digital processor subsystem.     

Analysis of remote reflection spectroscopy to monitor plant health.

Remote non-contact reflection spectroscopy is examined as a method for detecting stress in Controlled Ecological Life Support System CELSS type crops. Lettuce (Lactuca [correction of Latuca] Sativa L. cv. Waldmans Green) and wheat (Triticum Aestivum L. cv. Yecora Rojo) were grown hydroponically. Copper and zinc treatments provided toxic conditions. Nitrogen, phosphorous, and potassium treatments were used for deficiency conditions. Water stress was also induced in test plants. Reflectance spectra were obtained in the visible and near infrared (400nm to 2600nm) wavebands. Numerous effects of stress conditions can be observed in the collected spectra and this technique appears to have promise as a remote monitor of plant health, but significant research remains to be conducted to realize the promise.