新概念入门第三册 55 PART B
[audio]http://sound.yywz123.com/tingbbs/xgnrm/xgnrmdsc/55b.mp3[/audio]Lesson 55 PART B
From the earth:Greetings
It is impossible to look for life on another planet using earth-based telescope. (1)_______________________. Even a telescope in orbit round the earth, like the very successful Hubble telescope, would not be suitable because of the dust particles in our solar system. (2)_______________________. Once we detect a planet, we would have to find a way of blotting out the light from its star,so that we would be able to 'see' the planet properly and analyze its atmosphere. In the first instance , we would be looking for plant life,rather than ' little green men'.The life forms most likely to develop on a planet would be becteria. It is bacteria that have generated the oxygen we breathe on earth. For most of the earth's history they have been the only form of life on our planet. (3)_______________________. But this hope is always in the realms of science fiction. If we were able to discover lowly forms of life like bacteria on another planet, it would completely change our view of ourselves. As Daniel Goldin of NASA observed,'Finding life elsewhere would change everything. No human endeavour or thought would be unchanged by it.'
**** Hidden Message *****
页:
[1]