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The Sky at Night Phần 2

Các hình ảnh của các cụm, tinh vân và thiên hà là tốt nhất từng được chụp. Ngoài ra, hình ảnh được gửi trở lại của các thiên hà xa xôi trong phạm vi cho thấy rằng chúng tôi đã nhìn lại lịch sử từ rất sớm của vũ trụ. | 1 Eye on the Universe 3 the telescope really excelled. The images of clusters nebulae and galaxies are the best ever taken. Also pictures sent back of the remotest galaxies within range showed that we were looking back at the very early history of the universe. In every way the Hubble Space Telescope has been an astounding success - and remember it has cost less then a nuclear submarine Originally it was planned to operate for 15 years and this it has now done but all the time it is sending back new data and to lose it would be a scientific disaster. Moreover no replacement can be sent up before 2012 at the earliest and probably not for some years after that. The planned James Webb Space Telescope will be larger than Hubble but will concentrate upon infra-red research. Unlike Hubble it will not orbit the Earth. It will be sent to one of the Langrangian points a position near the Earth s orbit which is stable. It will be well away from any terrestrial interference but it will be a million miles away from us and no servicing missions will be possible so that the designers must do their best to get everything right first time Whatever happens Hubble will continue to work for several years yet. It was at first planned to bring it back to Earth without damaging it. When this was deemed to be too difficult there was a proposal to boost it into a higher orbit above all the resting part of the atmosphere and simply leave it there until we developed techniques to make it possible to fish down. Now alas there is a serious proposal to de-orbit it and allow it to burn away as it comes down. There are dangers here too because it is a relatively massive structure and it could well fall into an inhabited area. I know that all astronomers - and indeed all non astronomers too - would be sad to see us destroying one of our very best achievements. Let us hope this does not happen. The threat seemed imminent in 2005 when our programme was transmitted but receded when NASA changed its