擒数网 （随信APP) | 朱庇特的卫星上是否可能存在生命？ NASA将前往进行调查

欧罗巴上是否有可能存在生命成分？- 版权NASA/JPL-Caltech/SETI研究所/法新社提供

华盛顿报道：Chandan KHANNA和Lucie AUBOURG

在我们太阳系中还有其他地方可以支持生命吗？一枚宏伟的NASA探测器计划于星期一发射，进行为期五年半的旅程前往木星的一颗名为欧罗巴的卫星，迈出对寻找生命的第一步。

欧罗巴飞船任务将使美国太空机构探索这颗卫星的新细节，科学家们相信它可能在冰冷表面下拥有一片液态水海洋。

据NASA在一份声明中表示，发射将安排在10月14日星期一以后的某个日期在佛罗里达州卡纳维拉尔角搭乘SpaceX猎鹰重型火箭。

“欧罗巴是我们寻找地球以外生命最有希望的地方之一，”NASA官员吉娜·迪布拉西奥在上个月的新闻发布会上表示。

该任务不会直接寻找生命的迹象，而是将回答一个问题：欧罗巴是否包含可能支持生命存在的成分？

如果是的话，随后会有另一项任务前往进行探测。

“这是我们探索的一个机会,不是一个可能数十亿年前可能有生命的世界，”欧罗巴飞船项目科学家柯特·尼邦上个月告诉记者，“而是一个可能在今天，即时可能适合生命居住的世界。”

这个探测器是NASA设计的迄今为止最大的星际探测器。

当它庞大的太阳能板完全展开时，宽度为30米，设计用于获取到达木星的微弱光线。

– 原始生命？–

尽管欧罗巴的存在自1610年以来就已知晓，但第一次近距离拍摄是由1979年的旅行者探测器拍摄的，它揭示了其表面上红色的神秘线条。

下一个抵达木星冰冷卫星的探测器是NASA的加利罗探测器在1990年代，发现有可能该卫星上有一个海洋。

这次，欧罗巴飞船探测器将携带一系列先进仪器，包括摄像头，光谱仪，雷达和磁力仪，以测量其磁力。

任务将着眼于确定欧罗巴冰冷表面的结构和组成，其深度，甚至是其海洋的盐度，以及两者之间的相互作用 - 例如，水是否在某些地方上升到表面。

旨在了解是否存在生命所需的三大成分：水，能量和特定化合物。

如果这些条件存在于欧罗巴，生命可能以原始细菌的形式存在于海洋中，任务的副项目科学家波妮·布拉蒂解释说。

但是这些细菌可能对欧罗巴飞船来说太深来看见。

如果欧罗巴最终不适合居住呢？“这也会引发一系列新问题：我们为什么会认为是这样？为什么它不在那里？”NASA的副主管妮基·福克斯表示。

– 49次飞掠 –

这个探测器将在前往木星的途中覆盖29亿公里（18亿英里），预计在2030年4月抵达。

主要任务将持续四年。

探测器将在欧罗巴进行49次飞掠，距离表面最近可达25公里（16英里）。

它将遭受强烈辐射 - 相当于每次飞掠都接受数百万次胸部X光照射。

大约有4000人参与了耗时约十年的价值52亿美元的任务。

NASA表示这笔投资是有道理的，因为即将收集到的数据的重要性。

如果我们的太阳系最终是包括两个适宜居住的世界（欧罗巴和地球），“考虑一下，当你将这个结果延伸到这个星系中数以十亿计的其他太阳系时，那意味着什么，”欧罗巴飞船项目科学家尼伯尔表示。

“不考虑‘欧罗巴上是否有生命’这个问题，光是欧罗巴是否适宜居住的问题本身就为我们在星系中寻找生命打开了一个巨大的新范式，”他补充说。

欧罗巴飞船将与欧洲航天局（ESA）的“汁”的探测器同时运作，后者将研究木星的其他两颗卫星 - 木卫一和木卫二。

Does Europa contain the ingredients that would allow life to be present? - Copyright NASA/JPL-Caltech/SETI Institute/AFP Handout

Chandan KHANNA with Lucie AUBOURG in Washington

Is there anywhere else in our solar system that could support life? An imposing NASA probe is due to lift off on Monday on a five-and-a-half-year journey to Europa, one of Jupiter's many moons, to take the first detailed step toward finding out.

The Europa Clipper mission will allow the US space agency to uncover new details about the moon, which scientists believe could hold an ocean of liquid water beneath its icy surface.

Liftoff is scheduled for "no earlier than" Monday, October 14, from Cape Canaveral in Florida aboard a powerful SpaceX Falcon Heavy rocket, NASA said in a statement.

"Europa is one of the most promising places to look for life beyond Earth," said NASA official Gina DiBraccio at a news conference last month.

The mission will not look directly for signs of life but will instead look to answer the question: Does Europa contain the ingredients that would allow life to be present?

If it does, another mission would then have to make the journey to try and detect it.

"It's a chance for us to explore not a world that might have been habitable billions of years ago," like Mars, Europa Clipper program scientist Curt Niebur told reporters last month, "but a world that might be habitable today, right now."

The probe is the largest ever designed by NASA for interplanetary exploration.

It is 30 meters wide when its immense solar panels — designed to capture the weak light that reaches Jupiter — are fully extended.

- Primitive life? -

While Europa's existence has been known since 1610, the first close-up images were taken by the Voyager probes in 1979, which revealed mysterious reddish lines crisscrossing its surface.

The next probe to reach Jupiter's icy moon was NASA's Galileo probe in the 1990s, which found it was highly likely that the moon was home to an ocean.

This time, the Europa Clipper probe will carry a host of sophisticated instruments, including cameras, a spectrograph, radar, and a magnetometer to measure its magnetic forces.

The mission will look to determine the structure and composition of Europa's icy surface, its depth, and even the salinity of its ocean, as well as the way the two interact — to find out, for example, if water rises to the surface in places.

The aim is to understand whether the three ingredients necessary for life are present: water, energy and certain chemical compounds.

If these conditions exist on Europa, life could be found in the ocean in the form of primitive bacteria, explained Bonnie Buratti, the mission's deputy project scientist.

But the bacteria would likely be too deep for the Europa Clipper to see.

And what if Europa isn't habitable after all? "That also opens up a whole wealth of questions: Why did we think this? And why is it not there?" said Nikki Fox, an associate administrator at NASA.

- 49 flybys -

The probe will cover 2.9 billion kilometers (1.8 billion miles) during its journey to Jupiter, with arrival expected in April 2030.

The main mission will last another four years.

The probe will make 49 close flybys over Europa, coming as close as 25 kilometers (16 miles) above the surface.

It will be subjected to intense radiation — the equivalent of several million chest x-rays on each pass.

Some 4,000 people have been working on the $5.2 billion mission for around a decade.

NASA says the investment is justified by the importance of the data that will be collected.

If our solar system turns out to be home to two habitable worlds (Europa and Earth), "think of what that means when you extend that result to the billions and billions of other solar systems in this galaxy," said Niebur, the Europa Clipper program scientist.

"Setting aside the 'Is there life?' question on Europa, just the habitability question in and of itself opens up a huge new paradigm for searching for life in the galaxy," he added.

The Europa Clipper will operate at the same time as the European Space Agency's (ESA) Juice probe, which will study two other moons of Jupiter — Ganymede and Callisto.