英語聽力文摘 AMANDA望遠鏡

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https://online2.tingclass.net/lesson/shi0529/0007/7643/199.mp3

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A Deep Hole in the Pole

AMANDA望遠鏡(新華社電訊稿用的是“南極μ介子和高能中微子探測器陣列”名字)，被埋藏在南極冰塊下1.5公里深處。路透社2001年3月21日報道，這臺望遠鏡首次探測到中微子。中微子的發(fā)現(xiàn)將為科學家研究神秘的黑洞、γ射線爆發(fā)和恒星爆炸提供啟示。這臺望遠鏡有667個光學模塊，它在冰層深處往下看而不是往上看以尋找宇宙射線與大氣層碰撞后出現(xiàn)的大氣中微子。

'A Deep Hole in the Pole' on today's moment of science.

Nowadays we have telescopes of all different sorts, from ones that orbit the planet to giant radio dishes in the deserts. The neatest new idea for a telescope, though, is a deep hole in the pole.

AMANDA II stands for Antarctic Muon and Neutrino Detector Array. You know what “Antarctic” means: this baby lives at the south pole. The international project members who built it dug half a mile down into polar ice. Then they lowered in a series of light detectors, on the lookout for one of the most elusive particles in the universe: the neutrino.

Neutrinos are so tiny and zippy they can pass through the entire planet without hitting anything. Every now and then, however, one will collide with something–say a water molecule in the crystal-clear polar ice. When neutrino meets molecule, tell-tale flashes are given off,and AMANDA registers these.

Now comes the really neat part: that makes AMANDA into a kind of telescope. Imagine some cool extra-galactic event, like a supernova or the collision of two black holes. This gives off a stream of neutrinos, some of which travel to earth and make it almost through the planet, only to tag a water molecule on the way out.

AMANDA spots the collision and, because neutrinos travel in straight lines, tells exactly which direction the neutrino came from. With that,scientists can generate a neutrino map of the sky.

Telescopes are old, but a neutrino telescope is new. Odd as it may sound, this deep hole in the ice is helping researchers dig even deeper into space and time.