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Sten Odenwald

Publications and source records attributed to Sten Odenwald.

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Principles Of Heliophysics: a textbook on the universal processes behind planetary habitability

Heliophysics is the system science of the physical connections between the Sun and the solar system. As the physics of the local cosmos, it embraces space weather and planetary habitability. The wider view of comparative heliophysics forms a template for conditions in exoplanetary systems and provides a view over time of the aging Sun and its magnetic activity, of the heliosphere in different settings of the interstellar medium and subject to stellar impacts, of the space physics over evolving planetary dynamos, and of the long-term influence on planetary atmospheres by stellar radiation and wind. Based on a series of NASA-funded summer schools for early-career researchers, this textbook is intended for students in physical sciences in later years of their university training and for beginning graduate students in fields of solar, stellar, (exo-)planetary, and planetary-system sciences. The book emphasizes universal processes from a perspective that draws attention to what provides Earth (and similar (exo-)planets) with a relatively stable setting in which life as we know it could thrive. The text includes 200 "Activities" in the form of exercises, explorations, literature readings, "what if" challenges, and group discussion topics; many of the Activities provide additional information complementing the main text. Solutions and discussions are included in an Appendix for a selection of the exercises.

astro-ph.SR

A Study of External Galaxies Detected by COBE-DIRBE

A comparison of the COBE, Diffuse Infrared Background Experiment (DIRBE) all-sky survey with the locations of known galaxies in the IRAS Catalog of Extragalactic Objects and the Center for Astrophysics Catalog of Galaxies led to the detection of as many as 56 galaxies. In this paper, we present the photometric analysis of these detections and an analysis of their dust properties. The sample is dominated by late-type spirals and active galaxies, and their far-IR continuua between 25-240 microns suggest a single dust component dominating the far-IR emission. We show that for the spirals, T(dust)= 27.6 K, and for the active galaxies, T(dust) = 35.5 K. Estimates of the ratio of the mass of the dust component detected at T(dust) = 20 - 30 K to a hypothetical component with T(dust) = 15 K provide modest constraints to the Very Cold Dust (VCD) component present in the galaxies detected at 140 and 240 microns. VCD components with less than times the mass of the 20-30 K dust are consistent with all of the upper limits.

astro-ph