纪录片《火星任务》 第16期 好奇号(在线收听) |
Curiosity can call home 好奇号可借助 using two ultra-high-frequency radios. 两个超高频天线与我们联系 But the distance between Mars and Earth, 但是火星与地球间遥远的距离 together with the rover's limited power, 再加上火星车有限的功率 makes it difficult to pick up the signal. 使接收信号变得十分困难 It's a problem anyone with a car radio knows well. 有车载收音机的人都明白这个问题 We're about a hundred miles outside of Los Angeles. 我们离洛杉矶已经有几百公里远 In the car, I've got the radio going, 在车里 我依然能收到广播 but my favourite radio station is almost gone. 但我最喜欢的电台已经几乎没信号了 I'm not that far, certainly compared to Mars, 与火星地球之间距离相比 这并不很远 and the radio station that I listen to 并且我收听的这个电台 has a 90,000-watt transmitter, 拥有一台九万瓦的发射机 and so you'd wonder why I can't pick up the station here. 你可能会问 为什么在这里收不到信号 The problem is my little antenna 问题是我的车载小天线 is just not capable of picking up the signal at this distance, 就是不能接收到那么遥远的信号 no matter how powerful it seems the transmitter back at home is. 这与电台发射器功率的大小无关 |
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