英语听力：自然百科 行星旅行指南：木星 Jupiter—4

 Jupiter is a planet that knows how to exert its influence on the solar system, and how to impress even the season traveler. You can fly around the earth in a jumbo jet in less than two days. Try this on Jumbo Jupiter and you’ll be in the air for three solid weeks refueling about 50 times. Not only will you get sick of the food, there’s nowhere to land. 

 

  You don't actually have a surface of Jupiter. You shine a big strong radar¹ pulse at Jupiter, and what you get back is four tiny blips. You see the moons of Jupiter just fine, in fact we can study them by radar, Jupiter isn’t there, it’s like a stealth planet. If you have radar eyes, you’d wonder what these things were circling.  

 

  For a stealthy planet, Jupiter makes a big blip on the space travel radar. And it’s a target worth a trip. The best way to testify a trip to Jupiter is to retrace² the extraordinary journey of the only spacecraft to orbit it. Launched by shuttle, the Galileo spacecraft left earth in 1989 for an odyssey³ that lasted for 14 years. The first three were spent simply trying to leave the neighborhood with enough speed to go the distance. Three times farther than Mars, about half a billion miles, the road to Jupiter is a long one with a few bumps along the way.

1 radar   

n.雷达，无线电探测器

参考例句：

• They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
• Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。

2 retrace   

v.折回；追溯，探源

参考例句：

• He retraced his steps to the spot where he'd left the case.他折回到他丢下箱子的地方。
• You must retrace your steps.你必须折回原来走过的路。

3 odyssey   

n.长途冒险旅行；一连串的冒险

参考例句：

• The march to Travnik was the final stretch of a 16-hour odyssey.去特拉夫尼克的这段路是长达16小时艰险旅行的最后一程。
• His odyssey of passion, friendship,love,and revenge was now finished.他的热情、友谊、爱情和复仇的漫长历程，到此结束了。