VOA慢速英语2017 探测器卡西尼号结束服役 坠入土星（在线收听）

NASA's Cassini Death Dives into Saturn, Ending Mission

The spacecraft Cassini ended its 20-year mission on Friday with a final death dive into the planet Saturn.

卡西尼宇宙飞船周五最后一次冲向土星，结束了它20年的使命。

NASA scientists and officials gathered at California’s Jet Propulsion Laboratory (JPL) for Cassini’s last moments.

美国宇航局的科学家们和相关官员聚集在加州的喷气推进实验室见证了卡西尼的最后时刻。

“Project manager, flight director. Go ahead. Ok, we call loss of signal at one-one, five-five, four-six.”

“项目负责人、飞行指挥官。继续前进，我们认定丢失信号是在11点55分46秒。”

Cassini had actually burned up like a meteor 83 minutes earlier, as it dove through Saturn’s atmosphere. But it took that many minutes for the news to reach Earth more than one-and-a-half billion kilometers away.

卡尼西实际上在83分钟之前进入土星大气层之时已经像流星一样烧毁。但是这条消息花费了许多分钟时间才抵达超过1.5亿公里之外的地球。

Program manager Earl Maize marked the end of the spacecraft and praised the work of the NASA team.

项目经理厄尔·梅兹（Earl Maize）为卡西尼划上了一个句号，并且盛赞了美国宇航局团队的工作。

“I hope you’re all as deeply proud of this amazing accomplishment, congratulations to you all. This has been an incredible mission, an incredible spacecraft and you’re all an incredible team. I’m going to call this end of mission.”

他说：“我们希望你们都能为这项惊人成就深感自豪，祝贺大家。这是一项令人难以置信的任务，一艘令人难以置信的宇宙飞船。你们大家是一个不可思议的团队。我即将宣布任务结束。”

The crash was planned by scientists and engineers at NASA’s JPL. NASA is the United States space agency. They decided to end the mission this way because of an important find during the mission -- the possibility of life on one of Saturn’s moons.

这次坠毁是美国宇航局喷气推进实验室的科学家和工程师们策划的。他们决定以这种方式结束任务，是因为任务期间的一项重要发现，那就是土星其中一颗卫星上可能有生命。

Saturn is the sixth planet in our solar system. It is known for its famous rings and many moons. Cassini’s study of the system of Saturn’s rings and moons brought many surprises. The researchers discovered ocean worlds that may contain the elements for life on some of Saturn's moons.

土星是太阳系中的第六颗行星。它以其著名光环和卫星众多而闻名。卡西尼对土星光环和卫星体系的研究带来了许多惊喜。研究人员发现土星一些卫星的海洋环境中可能包含生命元素。

Morgan Cable is an assistant project science systems engineer.

摩根·卡贝尔（Morgan Cable）是一名助理项目科学系统工程师。

"At the time of its design, we had no idea that ocean worlds existed in the outer solar system."

他说：“在设计卡西尼的时候，我们完全没想到外太阳系存在海洋环境。”

Another unexpected discovery came from the south pole of Enceladus, a moon that sits in one of Saturn's rings. Molly Bittner is a spacecraft operations systems engineer. She explains what they found out about Enceladus.

另一项意外发现来自土卫二的南极，这是土星光环带上的一颗卫星。莫莉·比特纳（比特纳）是一名航天器操作系统工程师。她解释了他们对土卫二的一些发现。

"It has a liquid water ocean underneath and it shoots geysers. So these cracks open up and geysers shoot out."

她说：“它拥有一片地下液态海洋并向外喷发间歇泉，所以这些裂缝裂开，间歇泉喷射而出。”

Instruments on Cassini have examined the grains and gas coming from that geyser plume. Engineer Morgan Cable explains that instruments on board Cassini helped researchers learn what was in that geyser plume.

卡西尼上的仪器已经检测了这些间歇泉喷射羽流的颗粒和气体。工程师卡贝尔解释说，卡尼西上携带的仪器帮助研究人员了解了间歇泉喷射羽流的成分。

"We know that there are salts. Now this is important for life because life needs certain minerals and salts to exist. We have very strong evidence that there are hydro-thermal vents down at that base of that ocean, at the ocean flood. Now any time you find hydro-thermal vents here on Earth, you find rich communities of organisms."

“我们知道里面含有盐，这对生命非常重要，因为生命需要一定的矿物质和盐才能生存。我们有非常强劲的证据表明，这片海洋底部存在热液喷口。在地球上任何时候找到热液喷口都能找到丰富的生物群落。”

Cassini was also able to gather data from Titan, Saturn’s largest moon. It has lakes and seas of liquid methane and ethane, instead of water. There is also evidence of a liquid ocean beneath the surface that probably contains ammonia and water. Scientists and engineers say the environment could hold life. Morgan Cable says life may look different than on our planet.

卡西尼还能从土星最大的卫星土卫六上收集数据。土卫六上有液态甲烷和乙烷的湖泊和海洋，而不是水。还有证据表明其表面之下的液态海洋可能含有氨与水。科学家和工程师们表示，这种环境可以维持生命。卡贝尔表示，这类生命可能跟我们地球上的生命有所不同。

"We're still open to trying to look for weird life in places like this and we found a strange place right here in our solar system."

他说：“我们仍然愿意尝试在这类地方寻找怪异的生命，并且我们就在太阳系中就发现了一些奇怪的地方。”

The possibility of life on Saturn’s moons made NASA engineers think about how to best end Cassini’s mission as it ran out of fuel. Cassini carried organisms from Earth. They did not want it to land on a moon like Enceladus because, if it already holds life, Cassini could have contaminated it.

土星的卫星上可能存在生命，这点使得美国宇航局的工程师们考虑在卡西尼耗尽燃料之际如何最好地结束其使命。卡西尼携带了地球微生物。他们不想卡尼西登陆到土卫二这样的卫星上，因为如果它已经拥有生命，卡西尼可能会让它受到污染。

"I want to find life elsewhere in a place like Enceladus but I don't want to realize later on that we put it there."

他说：“我希望在像土卫二这样的地方找到生命，但是不希望随后发现是我们自己弄上去的。”

Scientists and engineers are already looking ahead to future missions back to Saturn and its moons. Cable says they want to look deeper into the possibility of finding life there.

科学家和工程师们已经开始展望未来重返土星及其卫星的任务。卡贝尔表示，他们希望更深入地探索在那里发现生命的可能性。

"And I think with today's instrumentation, things that we could put on a spacecraft right now, we could find that life with our instruments of today."

卡贝尔说：“我认为有了如今这些可以放进航天器内的仪器和物品，我们可以利用它们更好地寻找那些生命。”

Right up until it crashed into Saturn, Cassini was still sending back important data to Earth. That information will keep researchers busy as they analyze it for years to come.

卡西尼直到坠向土星仍在向地球发回重要数据。这些信息将使研究人员在未来几年分析它们时更加繁忙。

I’m Anne Ball.

Words in This Story

meteor – n. a piece of rock or metal that burns and glows brightly in the sky as it falls from outer space into the Earth's atmosphere

solar system – n. our sun and the planets that move around it

geyser – n. a hole in the ground that shoots out hot water and steam

plume – n. something (such as smoke, steam, or water) that rises into the air in a tall, thin shape

hydro thermal – adj. of or relating to hot water —used especially of the formation of minerals by hot solutions rising from a cooling magma

vent – n. an opening through which air, steam, smoke, liquid, etc., can go into or out

contaminate – v. to make (something) dangerous, dirty, or impure by adding something harmful or undesirable to it