Glossary term: Refração
Description: Refração é a forma como uma onda - e, especificamente, a luz - muda de direção ao passar de um meio para outro. A magnitude e a direção da mudança dependem dos "índices de refração" dos dois meios, que, por sua vez, dependem da velocidade da luz em cada meio, uma relação que é descrita matematicamente na lei de refração de Snell. A maneira como a luz passa em um pedaço de vidro pode ser usada para criar uma lente, que agrupa raios de luz paralelos - como a luz de uma estrela distante - que caem sobre a lente. Esse é o principal efeito usado na construção de telescópios refratores. A refração também depende do comprimento de onda da luz que incide, um fato que pode ser usado como em um prisma para separar a luz por comprimento de onda em suas cores elementares constituintes, o que é importante para documentar e examinar espectros.
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.
In Other Languages
- Árabe: الانكسار
- Alemão: Brechung
- Inglês: Refraction
- Francês: Réfraction
- Italiano: Rifrazione
- Chinês Simplificado: 折射
- Chinês Tradicional: 折射
Related Media
24 Hours of Rainbow
Caption: Honorable mention in the 2023 IAU OAE Astrophotography Contest, category of Still images taken exclusively with smartphones/mobile devices.
This panoramic view taken with a smartphone of Livorno, Italy, showcases a series of vivid rainbows captured on three different days in December 2021. Rainbows are the result of sunlight being refracted by water droplets suspended in the air, typically after rainfall or during misty conditions. The water droplets act like a prism, breaking up (refracting) the sunlight into the various colours. The different wavelengths of light are refracted by different amounts, which is why we see this layering of colours. The photographer skillfully merged the most remarkable shots taken on different days to highlight the diverse sizes and brilliance of these rainbows. The locations at which the rainbows appear to be centred are different because each rainbow appeared when the Sun was at a different position in the sky. This composite image beautifully captures the transient yet mesmerising allure of rainbows, illustrating their fleeting appearance and gradual dissipation influenced by the shifting atmospheric conditions.
Credit: Fabrizio Guasconi/IAU OAE (CC BY 4.0)
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
