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- Comet orbits are mostly long ellipses, so they spend most of the time far from the sun, cold. 彗星的軌道大部份是很長(cháng)的橢圓;所以大部份時(shí)間離太陽(yáng)很遠;很冷.
- Like other meteor showers, such as the Perseids and the Orionids, the Leonids happen when Earth plows through a trail of debris left in the wake of a comet orbiting the sun. 類(lèi)似于英仙座流星雨，獵戶(hù)座流星雨以及其他流星雨，獅子座流星雨發(fā)生于地球在繞太陽(yáng)公轉過(guò)程中進(jìn)入充滿(mǎn)彗星碎片的流星體質(zhì)點(diǎn)溪流之中。
- In the late 1980s, however, scientists determined that something like the Kuiper Belt was needed to explain why many short-period comets orbit so close to the plane of the solar system. 到了1980年代末期，科學(xué)家認定一定存在著(zhù)類(lèi)似柯伊伯帶的東西，才可以解釋為何有很多的短周期彗星，其軌道如此貼近太陽(yáng)系平面。
- The spacecraft is in orbit around the moon. 該航天器在繞月球軌道運行。
- That comet is invisible to the unaided eye. 那顆彗星只用肉眼是看不到的。
- Earth crosses the orbit of Halley's Comet annually in October. 地球和哈雷彗星的軌道將于每年的十月份交叉。
- The space shuttle will orbit a weather satellite. 太空梭將把一個(gè)氣象衛星送入運行軌道。
- The launch vehicle lifts the satellite into orbit. 太空火箭將人造衛星送入運行軌道。
- A comet is at perihelion when it is closest (=very close) to the sun. 彗星最接近太陽(yáng)時(shí)，它就是在近日點(diǎn)。
- Something of circular form; a circle or an orbit. 圓形物體圓形物體; 圓圈或環(huán)形軌道
- The spacecraft is in orbit (ie moving in orbit) round the moon. 該航天器在繞月球軌道上飛行。
- If I had binoculars, I could see that comet clearly. 如果我有望遠鏡，我就可以清楚地看見(jiàn)那顆彗星。
- Marketing does not come within the orbit of his department. 市場(chǎng)推銷(xiāo)業(yè)務(wù)不歸他這一部門(mén)管。
- The comet's ice, heated by the sun, rapidly and spectacular sublimate to gas. 彗星上的冰塊在太陽(yáng)熱的作用下迅速而壯觀(guān)地升華成氣體。
- If a comet crosses the Earth's orbit, we pass through this trail each year. 如果彗星穿過(guò)地球軌道，我們就會(huì )每年經(jīng)過(guò)這條尾巴。
- The central portion of the head of a comet. 彗核彗星頭部的中心部分
- Why else might the comet have come undone? 是什么導致了慧星的滅亡?
- The satellite was launched into orbit around the moon. 衛星被發(fā)射進(jìn)入繞月球運行的軌道。
- The two spacecraft will link up (with each other) in orbit. 兩艘宇宙飛船將於軌道上(互相)連接。
- By now, putting satellites in orbit is old hat to space scientists. 現在，對航天科學(xué)家來(lái)說(shuō)，把衛星送入軌道已不是一樁新鮮事了。
