Loading...

Glossary term: Galáxia Irregular

Description: Uma galáxia irregular é um tipo de galáxia com pouca ou nenhuma simetria (tem uma morfologia ou forma distorcida). Normalmente, elas são menores do que as galáxias espirais e elípticas e geralmente contêm quantidades significativas de gás capaz de formar estrelas. A Grande e a Pequena Nuvem de Magalhães são galáxias irregulares, relativamente próximas (aproximadamente 160.000 anos-luz e 200.000 anos-luz) da Via Láctea, que podem ser observadas a olho nu do hemisfério sul da Terra.

Related Terms:



See this term in other languages

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".

If you notice a factual or translation error in this glossary term or definition then please get in touch.

Related Diagrams


Sculptor’s stars form hook shape with the curve of the hook pointing west

Sculptor Constellation Map

Caption: The constellation Sculptor with its brighter stars and surrounding constellations. Sculptor is surrounded by (going clockwise from the top): Cetus, Aquarius, Piscis Austrinus, Grus, Phoenix and Fornax. Sculptor is a southern constellation and thus the whole constellation is visible at some point in the year throughout the southern hemisphere. The whole constellation is also visible in equatorial and most temperate regions of the northern hemisphere. Parts of the constellation are also visible to the remaining northern temperate regions. Sculptor is best viewed in the evening in the late northern hemisphere autumn and late southern hemisphere spring. The irregular galaxy NGC 55, and the spiral galaxies NGC 253 and NGC 300 all lie in Sculptor. There are marked here with red ellipses. The y-axis of this diagram is in degrees of declination with north as up and the x-axis is in hours of right ascension with east to the left. The sizes of the stars marked here relate to the star's apparent magnitude, a measure of its apparent brightness. The larger dots represent brighter stars. The Greek letters mark the brightest stars in the constellation. These are ranked by brightness with the brightest star being labeled alpha, the second brightest beta, etc., although this ordering is not always followed exactly. The dotted boundary lines mark the IAU's boundaries of the constellations and the solid green lines mark one of the common forms used to represent the figures of the constellations. Neither the constellation boundaries, nor the lines joining the stars appear on the sky.
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope

License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons