放大圖片
經歷400年的改進,望遠鏡已成為主要的天文探索工具,要點名一支最具貢獻、最為人熟悉的望遠鏡,這項榮譽非哈勃太空望遠鏡莫屬。這台於1990年4月升空的望遠鏡,至今已達成多項科學成就,包括更準確地測量「造父變星」的距離,使天文學家能更精確計算已知宇宙的大小;此外,哈勃望遠鏡更測量出宇宙實際上正在加速膨脹中,這出乎意料之外的發現為天文學家提供了新的研究方向。至於最具影響力的哈勃照片,當舉「哈勃超深空」,照片在相當於滿月1/10大小的面積裡,記錄了超越130億年前約1萬個遙遠星系的狀況(圖)。不說你不知道,18年前,當哈勃傳回第一個影像時,天文學家才驚覺哈勃的主鏡竟存在嚴重的光學誤差(圖右),這個誤差要等到1993年尾才由太空梭的太空人修正過來。
The Hubble Space Telescope
Launched in 1990, the Hubble Space Telescope remains the most productive and famous telescope. It has accurately measured the distances to some Cepheid variable stars and enables astronomers to calculate the size of our visible universe. It has also discovered, to the surprise of astronomers, that the cosmos is expanding in an ever-increasing rate. On the other hand, the most famous Hubble image is what is known as the ‘Hubble Ultra Deep Field’. In an area as small as 1/10 of the full moon, the image recorded about 10,000 13 billion-year-old galaxies. It would be interesting to know that, in the early years, Hubble images were plagued by optical aberration (right of picture). The error was not corrected until the 1993 space shuttle service mission. ■甄枝強 資深天文愛好者
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