2007年VOA标准英语-US Spacecraft Takes New Look at Jupiter on Way
时间:2018-12-08 作者:英语课 分类:2007年VOA标准英语(二月)
By David McAlary
Washington
28 February 2007
A U.S. spacecraft has taken the closest images of Jupiter since the Galileo probe perished in a programmed dive into the huge planet's atmosphere four years ago. The spacecraft's destination is icy, distant Pluto 1, but the U.S. space agency NASA wanted to fly close to Jupiter on the way out to get a scientific update and a speed boost. VOA's David McAlary reports.
New Horizons spacecraft
More than 13 months after its launch, NASA's New Horizons spacecraft has made its closest pass to Jupiter on its 10-year voyage to Pluto. The head of NASA's science directorate and chief investigator 2 for the mission, Alan Stern, says the flyby has been eagerly awaited.
"Between the demise 3 of Galileo with the end of its very successful mission in 2003 and the arrival of the Juno Jupiter orbiter that we are all looking forward to in 2016, this is the only train going this way," said Alan Stern.
Jupiter's Little Red Spot
New Horizons has been taking pictures of Jupiter since January and will continue to dispatch them through June, but the close pass more than two million kilometers away is giving astronomers 4 another detailed 5 look at the gas giant, its rings, and its four biggest moons.
A mission scientist from the Southwest Research Institute in Boulder 6, Colorado, John Spencer, spoke 7 of the goals before Wednesday's Jupiter pass.
"We very carefully tailored our observations so we will be not repeating things that have have been done by the other seven missions that have already been to Jupiter," said John Spencer. "Sometimes we are just looking for changes."
Jupiter flyby trajectory 8
The observations have included Jupiter's auroras and its giant red spot, a swirling 9 centuries-old storm larger than Earth. New Horizons' advanced instruments have also peered at the planet's rings in an effort to find more tiny moons. In addition, it studied the surface composition of the big moons Gannymede; Callisto; Io, which has a volcano; and Europa, which is thought to have a liquid water ocean under a shell of ice.
The spacecraft will also become the first to take a trip down the long tail of Jupiter's magnetosphere, a wide stream of charged particles extending tens of millions of kilometers.
Alan Stern says the observations are intended as practice for the duties New Horizons faces at Pluto when it arrives in 2015.
"We have designed this particular flyby to be a stress test on our spacecraft to work out the kinks so that at Pluto, we do not learn a thing about our spacecraft, we have worked out those kinks at Jupiter, putting our spacecraft through 700 different observations," he said.
These observations are only one reason for the visit to Jupiter. The pass also lets the planet's strong gravity sling 10 it away, providing a 14,000 - kilometer per hour speed boost. This cuts the spacecraft's flight time to Pluto by three years.
After the Jupiter encounter, New Horizons' electronics will become dormant 11 for much of its cruise. Mission controllers will shut off all but the most critical systems and check in once a year to test those systems, calibrate 12 instruments, and correct the course if needed.
- Pluto is the furthest planet from the sun.冥王星是离太阳最远的行星。
- Pluto has an elliptic orbit.冥王星的轨道是椭圆形的。
- He was a special investigator for the FBI.他是联邦调查局的特别调查员。
- The investigator was able to deduce the crime and find the criminal.调查者能够推出犯罪过程并锁定罪犯。
- He praised the union's aims but predicted its early demise.他赞扬协会的目标,但预期这一协会很快会消亡。
- The war brought about the industry's sudden demise.战争道致这个行业就这么突然垮了。
- Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
- Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪,为什么只有土星有光环。 来自《简明英汉词典》
- He had made a detailed study of the terrain.他对地形作了缜密的研究。
- A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。
- We all heaved together and removed the boulder.大家一齐用劲,把大石头搬开了。
- He stepped clear of the boulder.他从大石头后面走了出来。
- They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
- The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。
- It is not difficult to sketch the subsequent trajectory.很容易描绘出它们最终的轨迹。
- The path followed by a projectile is called its trajectory.抛物体所循的路径称为它的轨道。
- Snowflakes were swirling in the air. 天空飘洒着雪花。 来自《现代汉英综合大词典》
- She smiled, swirling the wine in her glass. 她微笑着,旋动着杯子里的葡萄酒。 来自辞典例句
- The boy discharged a stone from a sling.这个男孩用弹弓射石头。
- By using a hoist the movers were able to sling the piano to the third floor.搬运工人用吊车才把钢琴吊到3楼。