冥王星之后 太阳系探索任务大盘点

发布时间：2015-06-04 00:00:00 点击：463

[导读] 对“新视野”号任务的高涨的热情刚刚平复，不就之后，我们还会为“朱诺”号、ExoMars、BepiColombo等一系列太阳系的探索任务激动不已。

中国科技网8月17日报道（张微 编译）过去的几年里，我们为太空探索的发展激动不已。我们见证了太空飞船访问火星、彗星67P，和冥王星，尤其是对冥王星的探索，标志着几十年来首次到达太阳系边缘。

对“新视野”号任务的热情高涨，我们也想知道是否有和飞跃冥王星一样让我们激动万分的太空事件(发现外星人除外)。目前，我们对太阳系已经有了一个基本的了解，比如在这个行星系统中，卫星、光环和行星如何相互影响，以及它们的大气构成是什么样的。我们也从理论上推测了太阳系的形成与演化。但我们在完成探索太阳系并检验这些理论方面还有很长的一段路要走。未来十年及以后的时间里，几个太空任务将帮助我们揭开宇宙的新奥秘。

接下来的任务是什么?

因为明年它仍会不断地传输测量数据，“新视野号”会继续其新的发现，但是接下来它将飞越冥王星的轨道之外的柯伊伯带。最理想的研究天体是去年刚刚发现的MU69。如果今年晚些时候能够批准这项任务，那么2019年将可能飞过这个天体，让我们更好地研究这个神秘对象，帮助我们了解太阳系边缘发生过什么，太阳系是如何形成的。

2016年7月，美国宇航局的“朱诺”号探测器将抵达木星轨道，这是2003年“伽利略”号探测器任务结束之后，首个到达木星的航天器。“朱诺”号将研究木星的内部情况，了解它的组成成分，这能够启发我们有关太阳系形成的信息。它还将研究木星的极光以及这个星球如何与它巨大的磁层(太阳系中最大的物理结构)相连接。

欧洲的ExoMars任务将于2016年发射The Trace Gas Orbiter，这个轨道器使用两个航天器寻找火星上生命的迹象。也将研究火星大气中挥发性气体如水、甲烷和臭氧等的分布情况，所有这些将为生命的存在提供证据。它还将为一个火星车提供通讯转接服务，这个火星车将于2018年发射，它将在火星表面钻两米的深度来搜索类似的生物特征。

还有欧洲与日本合作的水星探测BepiColombo任务将于2017年发射，两个航天器将承担对水星内部、地表和磁层的详细研究任务，2018年，日本的隼鸟2号飞船将穿越地球轨道，抵达阿波罗小行星中的一个，经过一年的调查后，在2020年带着样品返回地球。

这样持续到未来，我们可以期待出现大的成果。2022年，欧洲航天局(ESA)将发射Jupiter Icy Moon Explorer (JUICE)任务，花费十年的时间到达太阳系中最大的卫星木卫三。这将是我们第一次向这个巨行星轨道发射航天飞船。JUICE的主要目标是研究这个巨行星的卫星是否可能存在生命。一个NASA的任务，Europa Clipper在本世纪20年代晚期或30年代早期，将探索木星的另一个卫星，欧罗巴。

即使有了这些任务计划，太阳系中仍然有很多地方值得我们再次访问。许多科学家已经不能满足于远距离的观测，而是想要从月亮、火星及其卫星火卫一上带回样本。这些能够带回样本的太空任务仍然需要技术的快速发展，才有可能实现。这些太空任务是人类探索外太空的基础，能够让我们测试技术，在我们把人类送上其他星球之前，侦查好太空的环境。

彗星也依然是太空科学家们关注的焦点。“主带彗星”，例如，一个最近发现的位于小行星带的彗星和可能能够提供地球上水来源的关键线索。最近发现的金星上的火山活动也是非常吸引大气科学家和地质学家们的关注，能够让我们仔细观察这个地球的“邪恶双胞胎”。

我们对土星以外的太阳系研究的很少。天王星和海王星只接受过一次的任务计划，与冥王星的“新视野”号类似，分别是在1986年和1989年访问过一次。这些冰巨行星是一类独特的行星，与气体巨人木星和土星有很大差异。科学家们在过去十年一直在为冰巨人的回归进行争论。海卫一，海王星最大的卫星尤其令人感兴趣，因为它可能是被海王星捕获的柯伊伯带天体，所以与冥王星的起源类似。如果没有革命性的技术创新，那么海卫一就是我们探索类冥王星天体的唯一机会和线索。

有什么意义?

探索并提出我们来自何方的疑问是人类状态的一部分。许多科学上的重大问题，如“太阳系是如何演化的?”，“地球之外存在生命吗?”如果不探索宇宙就没法回到这些问题。“菲莱”的主要科学问题之一就是试图了解，为什么某些生物分子长成那个样子。

这些问题的答案是需要成本的。新视野号的成本大约7亿美元(4.5亿欧元)，虽然平均到每个美国公民头上仅仅2美元(1.3欧元)左右。但是这笔钱不都发射向太空了。太空探索的资金也需要用于支持我们日常依赖的其他行业领域，如全球通讯、气象观测和导航等行业。还要用于下一代科学家和工程师的教育，使他们有能力提出更大的问题，解答我们对行星系统的疑问。

英文原文：

After Pluto there's still plenty of the solar system left to explore

The past couple of years have been very exciting for space exploration. We've watched as spacecraft made visits to Mars, comet 67P and, just last week, Pluto, which for decades marked the edge of our solar system.

Given the fervour that surrounded New Horizons mission, it's fair to wonder whether anything could be as exciting as flying past Pluto (with perhaps the exception of discovering alien life). We have a basic understanding of our solar system – such as how moons, rings and planets interact in planetary systems, and what their atmospheres are made of. We also have theories about how the solar system was formed and has evolved. But we're far from finishing exploring our solar system and testing these theories. Several missions over the next decade and beyond will reveal new insights into our patch of the universe.

What's next?

New Horizons will continue to produce new discoveries as it transmits its measurements over the next year, but the next step is a fly-by of anotherKuiper Belt object beyond the orbit of Pluto. The preferred candidate is a body designated 2014 MU69 that was discovered just last year. If approval is granted later this year, a possible fly-by in 2019 could allow us to discovering more about this mysterious object and help us understand what happens at the very edge of our solar system and how it was formed.

In July 2016, NASA's Juno mission will enter orbit around Jupiter, the first spacecraft to do so since the end of the Galileo mission in 2003. Juno will study the interior of Jupiter, looking at its composition for information that could teach us about the formation of the solar system. It will also study Jupiter's aurora and how the planet connects with its enormous magnetosphere, the largest physical structure in the solar system.

Europe's ExoMars mission aims to search for signatures of life on Mars using two spacecraft. The Trace Gas Orbiter, due to launch in 2016, will study the distribution of volatile gases such as water, methane and ozone in Mars' atmosphere, all of which could provide evidence for life. It will also act as a telecommunications relay for a rover that will be launched in 2018, which will drill two metres under the surface of the planet in search of similar biosignatures.

There's more. The joint European-Japanese BepiColombo mission to Mercury will launch in 2017, with two spacecraft undertaking a detailed study of the planet's interior, surface and magnetosphere. And in 2018, Japan'sHayabusa 2 spacecraft will arrive at one of the Apollo asteroids that cross the Earth's orbit and, after surveying it for a year, will return samples to Earth in 2020.

Further into the future, we have a big first to look forward to. In 2022, the European Space Agency (ESA) will send the Jupiter Icy Moon Explorer (JUICE) mission on a 10-year journey to Ganymede, the largest moon in the Solar System. This will be the first time we have put a spacecraft in orbit around the moon of a giant planet. JUICE's primary aim is to study whether the moons of giant planets can be viable locations for life. A NASA mission called Europa Clipper will also explore another of Jupiter's moons, Europa, in the late 2020s/early 2030s.

Even with all of these planned missions, there are plenty of other corners of the solar system worth visiting again. Many scientists are not satisfied with simply making measurements from afar but want to get samples back from our moon, Mars and its moon Phobos. These so-called sample return missions still require a huge amount of technology development that will push our capabilities much further. But they are also a stepping stone to human explorationas robotic exploration allows us to test technology and reconnoitre distant hostile environments before we send humans.

Comets also continue to be a focus of attention for space scientists because there is no typical comet. "Main-belt comets", for example, are a recently discovered class of comet which reside in the asteroid belt and may hold the keys to understanding the source of Earth's water. The recent discovery of volcanic activity on Venus is also tempting atmospheric scientists and geologists to look again at Earth's "evil twin".

The outer solar system beyond Saturn is still very poorly explored. Uranus and Neptune have only received single fly-bys, similar to New Horizons at Pluto, with visits in 1986 and 1989 respectively. These ice giant planets form a unique class of planet and are quite different to the gas giants, Jupiter and Saturn. Scientists have been arguing for a return to the ice giants for the last decade. Triton, the largest moon of Neptune is of particular interest because it is suspected to be a Kuiper Belt object that has been pulled into orbit in a similar way to the origins of Pluto. Without radically new technology, Triton is the only opportunity we have to encounter a Pluto-type object multiple times.

What's the point?

It is part of the human condition to explore and ask questions about where we came from. Many of science's big questions, such as: "how did our Solar System evolve?" and "is there life beyond Earth?" aren't easy to answer without exploring the universe. One of Philae's main science questions was to try to unravel why certain biological molecules are shaped the way they are.

These answers also come with a cost. New Horizons cost around US$700m (£450m), although this only works out at about US$2 (£1.30) for each US citizen. But this cash wasn't just launched into space. The money for space exploration goes to the same industries that support other sectors we rely on, such as global communications, weather observations and navigation. The same scientists also educate the next generation of scientists and engineers who in turn will ask those same big questions and seek answers amongst the planets.

来源：中国科技网 2015年08月18日　10:43

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