文章来源:未知 文章作者:meng 发布时间:2010-04-22 00:38 字体: [ ]  进入论坛

Venus Express has completed an 'aerodrag' campaign that used its solar wings as sails to catch faint wisps(小捆,小缕) of the planet's atmosphere. The test used the orbiter as an exquisitely1(精巧地,精致地) accurate sensor2 to measure atmospheric3 density4 barely 180 km above the hot planet. During five aerodrag measurements last week, Venus Express' solar arrays and control systems were operated as one big flying sensor, with the solar arrays rotated at various angles to the direction of flight.

The special configuration5 exposed the wings to the vanishingly faint wisps of atmosphere that reach to the boundary of space around Venus, generating a tiny but measurable aerodynamic(空气动力学的) torque(转矩,扭矩) , or rotation6, on the satellite.

This torque can be measured very accurately7 based on the amount of correction that must be applied8 by reaction wheels, which counter-rotate inside the spacecraft to maintain its orientation9 in space.

Mimicking10 the vanes of a windmill

Starting on Monday, the solar panels rotated through five daily-changing sets of orientations11. While one panel remained perpendicular12 to(垂直于) the direction of flight, the other rotated in steps, gradually increasing the torque to be counter-balanced by the reaction wheels.

On the last day, 16 April, the solar arrays were rotated at plus and minus 45° to the atmospheric flow, mimicking the vanes(叶片,风向标) of a windmill, in order to gather additional information on the behaviour of the molecules13 of the atmosphere bouncing off the solar wings.

A very capable satellite

"The aerodrag campaign went without problem, and conclusively14 demonstrated that Venus Express can be securely and accurately used to sense the density of the planet's atmosphere. Venus Express has shown once again that it is a very capable satellite," said Spacecraft Operations Manager Octavio Camino.

Camino explained that the mission operations team will study last week's results to develop an optimised configuration for aerodrag campaigns in October and in 2011. Aerodrag testing was also conducted in 2008, 2009 and February 2010.

Continued positive results may enable Venus Express to conduct more sophisticated investigations15 deeper in the atmosphere, which would be of immense interest to planetary scientists.

The solar array on Venus Express comprise two symmetrical(匀称的,对称的) wings supporting gallium-arsenide solar cells. Their combined 5.7 sq m can generate up to 1400 W of power in Venus orbit.


1 exquisitely Btwz1r     
  • He found her exquisitely beautiful. 他觉得她异常美丽。 来自《简明英汉词典》
  • He wore an exquisitely tailored gray silk and accessories to match. 他穿的是做工非常考究的灰色绸缎衣服,还有各种配得很协调的装饰。 来自教父部分
2 sensor sz7we     
  • The temperature sensor is enclosed in a protective well.温度传感器密封在保护套管中。
  • He plugged the sensor into a outlet.他把传感器插进电源插座。
3 atmospheric 6eayR     
  • Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
  • Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。
4 density rOdzZ     
  • The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
  • The region has a very high population density.该地区的人口密度很高。
5 configuration nYpyb     
  • Geographers study the configuration of the mountains.地理学家研究山脉的地形轮廓。
  • Prices range from $119 to $199,depending on the particular configuration.价格因具体配置而异,从119美元至199美元不等。
6 rotation LXmxE     
  • Crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。
  • The workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。
7 accurately oJHyf     
  • It is hard to hit the ball accurately.准确地击中球很难。
  • Now scientists can forecast the weather accurately.现在科学家们能准确地预报天气。
8 applied Tz2zXA     
  • She plans to take a course in applied linguistics.她打算学习应用语言学课程。
  • This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
9 orientation IJ4xo     
  • Children need some orientation when they go to school.小孩子上学时需要适应。
  • The traveller found his orientation with the aid of a good map.旅行者借助一幅好地图得知自己的方向。
10 mimicking ac830827d20b6bf079d24a8a6d4a02ed     
v.(尤指为了逗乐而)模仿( mimic的现在分词 );酷似
  • She's always mimicking the teachers. 她总喜欢模仿老师的言谈举止。
  • The boy made us all laugh by mimicking the teacher's voice. 这男孩模仿老师的声音,逗得我们大家都笑了。 来自辞典例句
11 orientations 0fe4bdb2d2133dafeb851bee3d9c63d0     
n.方向( orientation的名词复数 );定位;(任职等前的)培训;环境判定
  • Welfare comparisons are also hindered by differences in orientations among economic systems. 经济制度之间倾向性的差别也会妨碍福利的比较。 来自辞典例句
  • Their different value orientations led to different results in literary creation. 价值取向的分野亦导致了不同的创作局面。 来自互联网
12 perpendicular GApy0     
  • The two lines of bones are set perpendicular to one another.这两排骨头相互垂直。
  • The wall is out of the perpendicular.这墙有些倾斜。
13 molecules 187c25e49d45ad10b2f266c1fa7a8d49     
分子( molecule的名词复数 )
  • The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
  • Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里,大分子裂变为小分子。
14 conclusively NvVzwY     
  • All this proves conclusively that she couldn't have known the truth. 这一切无可置疑地证明她不可能知道真相。 来自《简明英汉词典》
  • From the facts,he was able to determine conclusively that the death was not a suicide. 根据这些事实他断定这起死亡事件并非自杀。 来自《简明英汉词典》
15 investigations 02de25420938593f7db7bd4052010b32     
(正式的)调查( investigation的名词复数 ); 侦查; 科学研究; 学术研究
  • His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查,但没有发现什么。
  • He often sent them out to make investigations. 他常常派他们出去作调查。
TAG标签: satellite space solar Venus