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The launch of a prototype rocket designed to replace the aging shuttle has been delayed by bad weather. 旨在取代老化的航天飞机的火箭原型因为恶劣的天气而被推迟发射。 The slender(细长的,苗条的), 100m-tall Ares I-X vehicle is due to test technology crucial(关键的,决定性的) for the development of a manned craft. A combination of high wind speeds and clouds contributed to Nasa's decision to scrub the launch at Kennedy Space Centre in Florida. The experimental craft has two further four-hour launch windows(发射窗口) between 0800 and 1200 EDT on 28 and 29 October. The craft is the first new launch vehicle that Nasa has designed and built in more than three decades. Electric effect Prior to the scheduled take-off, a fabric1 cover designed to protect a probe on the nose of the craft whilst it was on the launch pad became tangled(纠缠的,紊乱的). It was finally released to a round of applause by the mission team. A ship that had sailed into the seas surrounding the launch site caused further delays. Finally, bad weather sealed the fate of the vehicle's first planned launch attempt. Winds at ground level were blowing above 20 knots, higher than allowed for launch, and clouds obscured(遮蔽,掩盖) the pad. The flight team were particularly concerned about the cloud coverage2, partly because they needed clear skies to watch the flight but also because of a problem known as "tribo-electrification(摩擦带电)". This phenomenon occurs when the rocket encounters water or ice droplets3(小滴,飞沫) in the clouds. As these collide with the rocket it causes a static charge(静电荷) to build up on the rocket's skin, creating interference with radio signals. This is a problem for the 1-X team, which needs clear signals to gather data from the 700 sensors4 wired throughout the vehicle designed to collect flight data. In addition, the team needed to be able to send a signal to a detonator(发爆剂,引燃剂) and explosives onboard the craft, which would be used to destroy it in case of an emergency. The slim-line rocket is a prototype of the Ares I craft, part of the Constellation5 programme intended to return the US to the Moon by 2020. However, a recent report has cast doubt on the future of the programme. The Augustine panel, which had been asked to review the US human spaceflight programme, published its report on 22 October. Although the panel supported the Ares I-X test flight, it questioned the need to develop the Ares I. In particular, the panel queried6 the cost and design of the craft as well as its development time. 点击收听单词发音
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