VOA标准英语2012--NASA Mars Rover Will Face Harrowing Descent, Landing
时间：2019-01-13 作者：英语课 分类：VOA标准英语2012年(八月)
NASA Mars Rover Will Face Harrowing Descent, Landing
Curiosity is the centerpiece of the $2.5 billion Mars Science Laboratory spacecraft, launched in November aboard an Atlas 1 V rocket.
It's traveled some 560 million kilometers toward its destination, the Red Planet.
Curiosity is a "Mars scientist's dream machine," said Deputy Project Scientist Ashwin Vasavada ahead of its launch. "This rover is not only the most technically 2 capable rover ever sent to another planet, but it's actually the most capable scientific explorer we've ever sent out," he said.
As seen in this NASA animation 3, Curiosity will be traveling at about 20,000 kilometers per hour when it hits the Martian atmosphere. It will have only seven minutes to reduce its speed for a soft landing. NASA engineers will not be able to control or even witness the events in real time. They call this period "seven minutes of terror."
Ideally, after a parachute deploys 4, engines will fire for a powered descent.
Curiosity will be lowered to the Martian surface on cables and cut loose. Then the rocket pack will blast off.
Curiosity is the size of a small car and has 17 cameras. It's much larger than previous rovers and can travel as far as 200 meters per day.
It's a nuclear-powered mobile laboratory.
The remote-controlled vehicle can gather samples of soil and rocks and analyze 5 them using instruments onboard.
The goal is to see if the area ever had environmental conditions that could have supported microbial life, explains Vasavada. "This mission is really about looking for those habitable environments, and not detecting life itself," he said.
A team of space agency scientists selected the landing site, the foot of a mountain within a deep, 150-kilometer-wide depression called Gale 6 Crater 7. Each layer of rock contains clues about the planet's evolution.
Curiosity will investigate Martian geology, weather and radiation levels during the mission, which is expected to last about two Earth years. . .the equivalent of one Martian year.
- He reached down the atlas from the top shelf.他从书架顶层取下地图集。
- The atlas contains forty maps,including three of Great Britain.这本地图集有40幅地图，其中包括3幅英国地图。
- Technically it is the most advanced equipment ever.从技术上说，这是最先进的设备。
- The tomato is technically a fruit,although it is eaten as a vegetable.严格地说，西红柿是一种水果，尽管它是当作蔬菜吃的。
- They are full of animation as they talked about their childhood.当他们谈及童年的往事时都非常兴奋。
- The animation of China made a great progress.中国的卡通片制作取得很大发展。
- It then deploys "decoy" programs designed to attract the virus. 然后，它释放“诱饵”去吸引病毒。
- But when that doesn't work, he deploys his secret defense mechanism. 但没有效果，它要施展绝密自卫武器了。
- We should analyze the cause and effect of this event.我们应该分析这场事变的因果。
- The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。
- We got our roof blown off in the gale last night.昨夜的大风把我们的房顶给掀掉了。
- According to the weather forecast,there will be a gale tomorrow.据气象台预报，明天有大风。