Astrobiology: An Astronomer's Perspective

In this review we explore aspects of the field of astrobiology from an astronomical viewpoint. We therefore focus on the origin of life in the context of planetary formation, with additional emphasis on tracing the most abundant volatile elements, C, H, O, and N that are used by life on Earth. We first explore the history of life on our planet and outline the current state of our knowledge regarding the delivery of the C, H, O, N elements to the Earth. We then discuss how astronomers track the gaseous and solid molecular carriers of these volatiles throughout the process of star and planet formation. It is now clear that the early stages of star formation fosters the creation of water and simple organic molecules with enrichments of heavy isotopes. These molecules are found as ice coatings on the solid materials that represent microscopic beginnings of terrestrial worlds. Based on the meteoritic and cometary record, the process of planet formation, and the local environment, lead to additional increases in organic complexity. The astronomical connections towards this stage are only now being directly made. Although the exact details are uncertain, it is likely that the birth process of star and planets likely leads to terrestrial worlds being born with abundant water and organics on the surface.Comment: 40 pages, 11 figures to be published in: XVII Special Courses at the National Observatory of Rio de Janeiro. AIP Conference Proceedings, Volume TB

The Effect of Dysfunctional Thought Processes on Subjective Well-Being and Job Satisfaction

While the dispositional approach to job satisfaction has received a good deal of recent attention, a fundamental deficiency in past dispositional research is a failure to use existing theories to explain why individuals are unhappy and dissatisfied with their jobs. Locke (1976), Judge (in press), and Judge and Hulin (in press) suggested that thinking processes should be studied in relation to job satisfaction. This study tested the thesis that the cognitive theory of depression, which focuses on irrational thought processes, will help in understanding both subjective well-being and job satisfaction. A causal model involving subjective well-being, job satisfaction, dysfunctional thought processes, and other relevant influences was hypothesized and tested using a stratified random sample of university employees. Ratings were obtained from two sources in order to reduce single-source bias. The results indicated strong support for the overall model and for the efficacy of dysfunctional thought processes