We have trouble discovering those sorts of bodies, much less studying them using just optical telescopes.

我们很难发现这类天体，更不用说用光学望远镜研究它们了。

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From end to end, the Milky Way's starry disk, observable with the naked eye and through optical telescopes, spans 120,000 light-years.

从一端到另一端，银河系布满星星的圆盘横跨12万光年，可以用肉眼和光学望远镜观察到。

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Dust is nowhere near as hot as a star, therefore optical telescopes cannot observe it.

尘埃温度远不及恒星，所以光学望远镜难以观测到。

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The Atacama's main advantage for optical telescopes is the stillness of the air, which stops stars twinkling.

ECONOMIST: Beneath the Southern Cross I stand

The sites of the planned optical telescopes are near big settlements, making it easy to equip them with electricity and other goodies.

ECONOMIST: Beneath the Southern Cross I stand

The largest optical telescopes on earth can distinguish between things that are separated by about one second of arc (a 1, 296, 000th of the celestial equator).

ECONOMIST: Pulsars: In a wink | The