Cosmoeducação: uma abordagem transdisciplinar no ensino de astronomia

This work proposes a transdisciplinary approach that integrates transpersonal psychology exercises with astronomy teaching, seeking to allow one to reintegrate the sky in his/her daily life, expand his/her environmental awareness and eventually experiment the unity between human and cosmos. This proposal intends to collaborate with the supplying of education, which lacks initiatives of this kind, with the promotion of an integration of the scientific knowledge with the human experience that transcends the materialistic and fragmentary objectives of the current educational system. As a result of that lack, the teachers formation is also poor as for an integral and transdisciplinary approach. Besides, we also approached in this research the necessity to propose alternatives so that the educators may work in a more assertive way with the environmental and anthropological crisis in which we are living. Our working hypothesis is that the contents of astronomy, when they are dealt in a holisticanthropological focus and are related with transpersonal psychology practices, can come to be an efficient cultural-academic vehicle, capable of propitiating an expansion of consciousness and changes in the way one conceives the world. Such changes are necessary so that a more solidary, fair and ecologically balanced life may come to exist and prevail in the planet. Part of the collection of data was done through the ethnographic method, once an anthropological interpretation is inextricably associated with this kind of educational intervention, which will naturally include ethno-visions of the universe as well as specific cultural elements. In the beginning the scope of this research was a group of students attending the Astronomy assignment in an undergraduate Geography course (UFRN), in which we accomplished participant observation, half-open interviews and the first experimental practices mentioned. After the evaluation of the first data collected from that initial group, we elaborated an academic extension course, Laboratory in Cosmoeducation, and we offered it to teachers of the 1st and 2nd cycles of the fundamental level of the Alceu Amoroso Lima State School, located in the North Zone of Natal. We prized self-experimentation in that course, so that the teachers could enrich their repertoire of personal experiences, stimulating meditative reflections and eventual changes in the ways of conceiving the world and in their pedagogical practice. The transdisciplinary attitude permeated all our educational action, because this approach transcends the boundaries of disciplines, seeking essentially the integral development of the human being. The process has made us realize that the practice of looking at the sky , as a way of reintegrating it into daily life, provokes a process of expansion of the consciousness and of reintegration of the self in a wider level of environmental interrelation. According to the results, the occurrence of conceptual and existential changes of the world vision of the participant teachers was evident, reassuring ourselves of the idea that the interface between astronomy teaching and the practices of transpersonal psychology can contribute to the recovery of a holistic relationship between the human being and the cosmos and to inspire the arising of a more wide-ranging ethics, based on universal, impartial and sustainable values

Progress toward a cosmic dust collection facility on space station

Scientific and programmatic progress toward the development of a cosmic dust collection facility (CDCF) for the proposed space station is documented. Topics addressed include: trajectory sensor concepts; trajectory accuracy and orbital evolution; CDCF pointing direction; development of capture devices; analytical techniques; programmatic progress; flight opportunities; and facility development.

Possible comet samples : The NASA Cosmic Dust Program

Beginning in 1974, a limited effort to collect extraterrestrial dust samples from the stratosphere using impactors mounted on NASA U-2 aircraft was initiated at NASA Ames Research Center (1). Subsequent studies (e.g. 1-9) have clearly established an extraterrestrial origin for some of the material. Attrition of comets is considered to be one of the potential sources of extraterrestrial dust(1,5). Additionally, some of the particles appear to represent a type of primitive material not represented in meteorite collections. In order to provide a greater availability of these samples to the scientific community, NASA-Johnson Space Center (JSC) began in May of 1981 a program dedicated to the systematic collection and curation of cosmic dust for scientific investigation. Collections were made at 18 to 20 km altitude by means of collectors mounted under the wings of a WB57F. When the aircraft reaches operating altitude, the collector plates (impactors) are extended into the ambient airstream with the collection surface normal to the airflow. To prevent particles from bouncing off the surface, the impactors are coated with a film of high viscosity silicone oil. The impactors are sealed in canisters to minimize contamination when not collecting.

Non-Gaussianities and Preheating from N-flation and Magnetogenesis via rotating cosmic string loops

In this thesis we examine multi-field inflationary models of the early Universe. Since non-Gaussianities may allow for the possibility to discriminate between models of inflation, we compute deviations from a Gaussian spectrum of primordial perturbations by extending the delta-N formalism. We use N-flation as a concrete model; our findings show that these models are generically indistinguishable as long as the slow roll approximation is still valid. Besides computing non-Guassinities, we also investigate Preheating after multi-field inflation. Within the framework of N-flation, we find that preheating via parametric resonance is suppressed, an indication that it is the old theory of preheating that is applicable. In addition to studying non-Gaussianities and preheatng in multi-field inflationary models, we study magnetogenesis in the early universe. To this aim, we propose a mechanism to generate primordial magnetic fields via rotating cosmic string loops. Magnetic fields in the micro-Gauss range have been observed in galaxies and clusters, but their origin has remained elusive. We consider a network of strings and find that rotating cosmic string loops, which are continuously produced in such networks, are viable candidates for magnetogenesis with relevant strength and length scales, provided we use a high string tension and an efficient dynamo.

Measuring the Cosmic Microwave Background : Topics along the analysis pipeline

The first quarter of the 20th century witnessed a rebirth of cosmology, study of our Universe, as a field of scientific research with testable theoretical predictions. The amount of available cosmological data grew slowly from a few galaxy redshift measurements, rotation curves and local light element abundances into the first detection of the cos- mic microwave background (CMB) in 1965. By the turn of the century the amount of data exploded incorporating fields of new, exciting cosmological observables such as lensing, Lyman alpha forests, type Ia supernovae, baryon acoustic oscillations and Sunyaev-Zeldovich regions to name a few. -- CMB, the ubiquitous afterglow of the Big Bang, carries with it a wealth of cosmological information. Unfortunately, that information, delicate intensity variations, turned out hard to extract from the overall temperature. Since the first detection, it took nearly 30 years before first evidence of fluctuations on the microwave background were presented. At present, high precision cosmology is solidly based on precise measurements of the CMB anisotropy making it possible to pinpoint cosmological parameters to one-in-a-hundred level precision. The progress has made it possible to build and test models of the Universe that differ in the way the cosmos evolved some fraction of the first second since the Big Bang. -- This thesis is concerned with the high precision CMB observations. It presents three selected topics along a CMB experiment analysis pipeline. Map-making and residual noise estimation are studied using an approach called destriping. The studied approximate methods are invaluable for the large datasets of any modern CMB experiment and will undoubtedly become even more so when the next generation of experiments reach the operational stage. -- We begin with a brief overview of cosmological observations and describe the general relativistic perturbation theory. Next we discuss the map-making problem of a CMB experiment and the characterization of residual noise present in the maps. In the end, the use of modern cosmological data is presented in the study of an extended cosmological model, the correlated isocurvature fluctuations. Current available data is shown to indicate that future experiments are certainly needed to provide more information on these extra degrees of freedom. Any solid evidence of the isocurvature modes would have a considerable impact due to their power in model selection.

Impact of cosmic inhomogeneities on SNe observations

We study the impact of cosmic inhomogeneities on the interpretation of SNe observations. We build an inhomogeneous universe model that can confront supernova data and yet is reasonably well compatible with the Copernican Principle. Our model combines a relatively small local void, that gives apparent acceleration at low redshifts, with a meatball model that gives sizeable lensing (dimming) at high redshifts. Together these two elements, which focus on different effects of voids on the data, allow the model to mimic the concordance model.