Os telescópios trabalham com a refração e a reflexão de Luz.

Transcrição

1 Telescópios

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3 Os telescópios trabalham com a refração e a reflexão de Luz. Quais as propriedades da luz que devemos conhecer para entender o funcionamento de um telescópio? Difração Reflexão e Refração Imagens: resolução e sensibilidade

4 Difração da Luz

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9 Difração

10 Difração O Interferência construtiva e destrutiva de ondas:

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12 Difração O O Diâmetro do espelho ou lente Influencia na resolução do telescópio!! Azul 1 rad = 360*60*60/2Pi segundos de arco

13 1 - Calcule a resolução angular dos telescópios abaixo, para o comprimento de onda de 400nm (luz visível): a) Telescópio de PVC, D = 3,6cm; b) Telescópio pequeno do laboratório, D = 10cm; c) Telescópio reflector do laboratório (Keck, Hubble, Magalhães e Soar), 15cm; d) Telescópio Celeston, D = 10 ; e) Soar, D = 4m; 2 - Caso estes telescópios tenham a mesma magnificação (aumento), qual deverá ser a diferença entre as imagens deles?

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15 Difração Com os nossos telescópios conseguimos ver a Andrômeda com esta resolução? NÃO!!! Tempo de exposição, seeing,...

16 Andes Chilenos: ESO, CTIO, SOAR

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18 Compensar o Seeing Ruim (1993):

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25 As lentes decompõe a luz como um prisma. Aberração Cromática

26 Maior Telescópio refletor 10m - Havai Maior Telescópio refrator 1m Yerkes

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29 Foco Newtoniano Foco Cassegrain

30 Foco Coudé

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39 The Very Large Telescope array (VLT) is the flagship facility for European ground-based astronomy at the beginning of the third Millennium. It is the world's most advanced optical instrument, consisting of four Unit Telescopes with main mirrors of 8.2m diameter and four movable 1.8m diameter Auxiliary Telescopes. The telescopes can work together, to form a giant interferometer, the ESO Very Large Telescope Interferometer, allowing astronomers to see details up to 25 times finer than with the individual telescopes. The light beams are combined in the VLTI using a complex system of mirrors in underground tunnels where the light paths must be kept equal to distances less than 1/1000 mm over a hundred metres. With this kind of precision the VLTI can reconstruct images with an angular resolution of milliarcseconds, equivalent to distinguishing the two headlights of a car at the distance of the Moon.

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45 The huge "dish" is 305 m (1000 feet) in diameter, 167 feet deep, and covers an area of about twenty acres. The surface is made of almost 40,000 perforated aluminum panels, each measuring about 3 feet by 6 feet, supported by a network of steel cables strung across the underlying karst sinkhole. It is a spherical (not parabolic) reflector. Suspended 450 feet above the reflector is the 900 ton platform. Similar in design to a bridge, it hangs in midair on eighteen cables, which are strung from three reinforced concrete towers. One is 365 feet high, and the other two are 265 feet high.

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49 Uma forma de melhorar a baixa resolução que se tem em ondas de rádio

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54 Gaia ESA - Europian Space Agency Lançado em 2013 pelo foguete russo Soyo (Guiana Francesa) Objetivo de fazer um mapa tridimensional do universo Medir com precisão distâncias, composições, movimento, T, etc de estrelas e galáxias Um substituto do Hubble Gaia is an ambitious mission to chart a three-dimensional map of our Galaxy, the Milky Way, in the process revealing the composition, formation and evolution of the Galaxy. Gaia will provide unprecedented positional and radial velocity measurements with the accuracies needed to produce a stereoscopic and kinematic census of about one billion stars in our Galaxy and throughout the Local Group. This amounts to about 1 per cent of the Galactic stellar population

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57 The purpose of the Cosmic Background Explorer (COBE) mission was to take precise measurements of the diffuse radiation between 1 micrometer and 1 cm over the whole celestial sphere. The following quantities were measured: (1) the spectrum of the 3 K radiation over the range 100 micrometers to 1 cm; (2) the anisotropy of this radiation from 3 to 10 mm; and, (3) the spectrum and angular distribution of diffuse infrared background radiation at wavelengths from 1 to 300 micrometers.

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