O espelho vai a caminho!
Já alguma vez se perguntou como é que um telescópio mantém os seus espelhos nas melhores condições para observar o cosmos? Na Fotografia da Semana de hoje, um camião transporta cuidadosamente um dos espelhos do Very Large Telescope (VLT) do ESO, bem embrulhado para se proteger do ambiente inóspito do deserto chileno do Atacama. O seu destino é a instalação de revestimento que mantém os espelhos deste telescópio perfeitamente brilhantes.
Apesar de estarem alojados em recintos que os protegem das condições extremas do deserto durante o dia, os espelhos do telescópio estão expostos aos elementos durante a noite e, por isso, precisam de ser limpos e revestidos para manter a sua refletividade. O pó que se acumula na sua superfície é removido regularmente através da pulverização de dióxido de carbono gelado. E aproximadamente todos os 18 meses, o espelho recebe um novo revestimento de alumínio. Para tal, o espelho tem de ser removido do telescópio e transportado lentamente pela encosta abaixo até à instalação de revestimento, que fica a alguns quilómetros de distância dos telescópios, no campo base do VLT. Durante o transporte, o espelho é acompanhado de perto por pessoal do ESO que caminha ao lado do camião de transporte. O Extremely Large Telescope (ELT) do ESO, visível ao fundo da imagem e atualmente em construção, observa silenciosamente esta cena a partir do topo do Cerro Armazones.
Nas instalações de revestimento, o espelho de 8,2 metros é separado da sua célula de suporte, uma estrutura que protege o espelho e mantém a sua forma, e é limpo para remover quaisquer contaminantes que possam danificar o processo de revestimento. A antiga camada fina de alumínio, crucial para a refletividade do espelho, é removida com uma lavagem química e substituída por uma nova. Após este processo que demora cerca de 8 dias, incluindo testes para verificar os resultados, o espelho restaurado é então transportado de volta para o VLT, onde pode voltar ao trabalho, colectando a luz que nos chega do espaço profundo.
Créditos:L. Sbordone/ESO
Sobre a imagem
| Id: | potw2620a |
| Língua: | pt |
| Tipo: | Fotográfico |
| Data de divulgação: | 18 de Maio de 2026 às 06:00 |
| Tamanho: | 7728 x 5152 px |
Sobre o objeto
| Nome: | Cerro Armazones, Extremely Large Telescope, Mirror, Very Large Telescope |
| Tipo: | Unspecified : Technology |
Formatos de imagens
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