US Space Agency Returns to Mars with InSight Lander
时间:2018-11-27 作者:英语课 分类:2018年VOA慢速英语(十一)月
The American space agency’s lander InSight is to arrive on Mars Monday. The event will mark the space agency’s return to the planet.
Unlike NASA’s Curiosity rover, which arrived in 2012, InSight will not move across the planet’s surface.
Instead it will become the first spacecraft used only for exploring underground. It will study the geology of Mars, seeking signs of Martian quakes.
InSight is a joint 1 U.S. and European project. The lander’s full name is Seismic 2 Investigations 3, Geodesy and Heat Transport. It is six meters long and 1.5 meters wide. It weighs 360 kilograms.
InSight’s 1.8-meter robotic arm will put in place two experiments. Both are designed to look deep under the surface to gain understanding about the structure of the planet.
One experiment, called SEIS, for Seismic Experiment for Interior Structure, will study seismic waves. These are waves of energy caused by quakes or objects that hit the planet.
NASA scientists say SEIS will be able to sense changes in speed as the waves travel through the planet. This could help scientists learn what Mars is made of. NASA says SEIS has a shell to protect it from wind, big temperature changes and other conditions.
Another InSight experiment is to dig into the planet. A temperature sensor 4 will be sent as far as 5 meters below the surface.
The device is designed to set itself firmly in place. It will measure temperature and look for evidence of volcanic 5 and other geological activity.
Another important experiment will use radio waves to study Mars’ “wobble.” More information about this movement could help scientists determine whether the planet’s core is liquid or solid. That knowledge might help explain why Mars is surrounded by a weak magnetic field.
Bruce Banerdt is the lead scientist for InSight with NASA’s Jet Propulsion Laboratory.
He described the spacecraft as a robot that can take care of itself.
“It’s got its own brain. It’s got an arm…It can listen with its seismometer. It can feel things with the pressure sensors 6 and the temperature sensors. It pulls its own power out of the sun,” he noted 7.
NASA’s science mission chief, Thomas Zurbuchen, said the results of the InSight project could “revolutionize the way we think about the inside of our planet.”
But, first, InSight will have to land on Mars with its sensitive instruments undamaged.
Since Mars exploration started in the 1960s, only about 40 percent of orbiters and landers have successfully carried out their work.
Tom Hoffman is InSight’s project manager. He said earlier successes do not lessen 8 the concerns for each new operation. “Just because we’ve done it before doesn’t mean we’re not nervous and excited about doing it again,” he said.
InSight will enter the Martian atmosphere traveling at 19,800 kilometers an hour. It will slow for landing on Elysium Planitia, a wide flat area near the planet’s equator.
If all goes well, InSight could deploy 9 its experiments in about 10 weeks. The InSight project is expected to continue for one Martian year, about two years on Earth.
I’m Mario Ritter Jr.
Words in This Story
wobble –n. to move with an unsteady side-to-side motion
core –n. the central part of something
- I had a bad fall,which put my shoulder out of joint.我重重地摔了一跤,肩膀脫臼了。
- We wrote a letter in joint names.我们联名写了封信。
- Earthquakes produce two types of seismic waves.地震产生两种地震波。
- The latest seismic activity was also felt in northern Kenya.肯尼亚北部也感觉到了最近的地震活动。
- 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。
- 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。
- There have been several volcanic eruptions this year.今年火山爆发了好几次。
- Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。
- There were more than 2000 sensors here. 这里装有两千多个灵敏元件。 来自《简明英汉词典》
- Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时,有很大变化。 来自辞典例句
- The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
- Jim is noted for arriving late for work.吉姆上班迟到出了名。