Maria de Fátima Oliveira Saraiva

Federal University of Rio Grande do Sul | UFRGS

A educação a distância (EAD) é uma importante alternativa para o ensino superior, mas na área de astronomia ainda há carência de materiais educacionais e avaliações sobre a qualidade de cursos ministrados nesta modalidade de ensino. Neste artigo relatamos uma experiência de cinco semestres consecutivos (de 2011/2a 2013/2) em que uma disciplina de a...

In this article we report the development and use of a CD of optics for high-school teaching, covering all topics for this level. The material contains didactic texts in HTML language, 77 animations and 64 images generated by ourselves, as well as 13 simulators (Java Applets) available in the internet. We comment about the application and reception...

Neste artigo descrevemos a elaboração de um teste de múltipla escolha sobre as fases da Lua e analisamos os resultados de sua aplicação em dez grupos de estudantes de Física da UFRGS. Durante o aprimoramento do teste notamos que a porcentagem de acertos a respeito de alguns conceitos teve um aumento significativo associado à reformulação da pergunt...

We present the structure of the basic school curriculum in Brazil, that for a few years has included astronomy, and comment on the strategies that universities are adopting for preparing the teachers for the new curriculum.

A lua cheia muda de cor conforme se eleva no céu. No nascente apresenta-se amarelada e depois, quando já se encontra elevada no céu, é branca. Durante um eclipse total, a Lua pode se apresentar com uma variedade de cores entre marrom e amarelo. Discutimos as razões pelas quais a lua cheia exibe cores variadas.

Resumo Quando um objeto intercepta a luz do Sol, a sua sombra sobre um anteparo diminui de tamanho à medida que aumenta a distância entre ele e o objeto. Finalmente, a uma distância grande compa-rada com as dimensões do objeto, a sombra deixa de existir. Apesar de o efeito ser bem conhecido no contexto da Astronomia, relacionado aos eclipses do Sol...

Neste trabalho propomos a construção de material didático de baixo custo para demonstração do conceito de fases de um corpo iluminado. O principal objetivo de nosso material é facilitar a compreensão das fases da Lua da perspectiva de um observador na Terra. O material ajuda na visualização de dois efeitos importantes: (1º) mesmo tendo sempre a met...

In this article we report the development and use of a CD of optics for high-school teaching, covering all topics for this level. The material contains didactic texts in HTML language, 77 animations and 64 images generated by ourselves, as well as 13 simulators (Java Applets) available in the internet. We comment about the application and reception...

In this article we report the development and use of a CD of optics for high-school teaching, covering all topics for this level. The material contains didactic texts in HTML language, 77 animations and 64 images generated by ourselves, as well as 13 simulators (Java Applets) available in the internet. We comment about the application and reception...

We present a detailed investigation of the incidence of circumnuclear dust structure in a large, well-matched sample of early-type galaxies with and without Active Galactic Nuclei (AGN). All 34 early-type AGN hosts in our sample have circumnuclear dust, while dust is only observed in 26% (nine) of a pair-matched sample of 34 early-type, inactive ga...

We present a detailed investigation of the incidence of circumnuclear dust structure in a large, well-matched sample of early-type galaxies with and without Active Galactic Nuclei (AGN). All 34 early-type AGN hosts in our sample have circumnuclear dust, while dust is only observed in 26% (nine) of a pair-matched sample of 34 early-type, inactive ga...

We report the discovery of fourteen new ZZ Cetis with the 4.1m Southern Astrophysical Research telescope, at Cerro Pachon, in Chile. The candidates were selected from the SDSS (Sloan Digital Sky Survey) DA white dwarf stars with Teff obtained from the optical spectra fit, inside the ZZ Ceti instability strip. Considering these stars are multi-perio...

High resolution B, V, I imaging of the inner region of the spiral barred galaxy NGC 7479 suggests this galaxy contains a pseudo nuclear ring and possibly a nuclear bar.

We present low signal-to-noise spectroscopy and surface photometry of two small galaxies, detected in the field of the nearby asymmetric barred spiral NGC$\,$7479, near a prolongation of the western arm that forms a faint tail in the disc, and selected as possible companions of this galaxy. The analysis was based on data obtained with the Prime Foc...

Conhecer as propriedades de galáxias a diferentes redshifts é uma questão fundamental para entender o problema da formação e evolução das galáxias, e desde a década passada tem se intensificado fortemente o estudo de galáxias muito distantes. No entanto parece haver um interesse menor em galáxias a distâncias intermediárias, que aparecem como objet...

Optical spectra were used to study the stellar population and gas emission, when present, in the central parts of the elliptical galaxies NGC 6958, NGC 6851 and ESO 185-G54, and the spiral galaxies NGC 5757, NGC 7412 and IC 4214. Stellar population properties were derived by comparing the equivalent widths of the absorption lines with those of gala...

We present BVRI CCD surface photometry for 4 elliptical and 2 S0 galaxies that show bright emission lines in their nuclear spectra. We obtained isophote maps, luminosity profiles, and basic photometric parameters. We also obtained continuum subtracted Hα +[NII] images for 5 galaxies in our sample, but only in two of them, NGC 6858 and ESO 185-54, w...

BVRI and Hα CCD surface photometry is presented for the Sab system IC 4214, an example of a galaxy with three rings and no conventional bar. We obtained isophote maps, luminosity profiles, and basic photometric parameters. The photometry suggests the galaxy has three major structural components: the nuclear bulge, the disk, and a non-axisymmetric c...

We present a brief report on the B, V, R, I , and H α CCD surface photometry of the southern SABab galaxy IC 4214. We obtained isophote maps, luminosity profiles, and basic geometric and photometric parameters in BV RI , and mapped the distribution of the gas through continuum subtracted Hα emission line images.