Some like it hot
某些人喜欢热辣

We’re about to fly a spacecraft into the Sun for the first time
我们即将首次将航天器飞向太阳

"Quite simply, we want to find the birthplace of the solar wind."
“简而言之，我们想要找到太阳风的起源地。”

Eric Berger – 2024年12月20日 07:02 | 135
埃里克·伯杰 – 2024 年 12 月 20 日 07:02 135

A rendering of the Parker Solar Probe with a Santa hat. Credit: NASA/Aurich Lawson
帕克太阳探测器戴上圣诞帽的渲染图。图片来源：NASA/Aurich Lawson

Twas the night before Christmas, when all through the Solar cycle,
这是圣诞前夜，当所有通过太阳周期，

Not a sunspot was stirring, not even a burst;
没有一丝太阳黑子在活动，连一闪而过的都没有；

The stockings were all hung by the corona with care,
袜子都挂在电晕带旁，小心又仔细，

In hopes that the Parker Solar Probe would soon be there.
期待帕克太阳探测器不久将抵达那里。

Almost no one ever writes about the Parker Solar Probe anymore.
几乎没有人再写帕克太阳探测器了。

Sure, the spacecraft got some attention when it launched. It is, after all, the fastest moving object that humans have ever built. At its maximum speed, goosed by the gravitational pull of the Sun, the probe reaches a velocity of 430,000 miles per hour, or more than one-sixth of 1 percent the speed of light. That kind of speed would get you from New York City to Tokyo in less than a minute.
当然，这艘宇宙飞船在发射时引起了一定的关注。毕竟，它是人类迄今为止建造的最快移动物体。在太阳引力的助推下，探测器达到其最高速度时，时速可达 43 万英里，即光速的六分之一多一点。这样的速度能让你在不到一分钟的时间内从纽约市抵达东京。

And the Parker Solar Probe also has the distinction of being the first NASA spacecraft named after a living person. At the time of its launch, in August 2018, physicist Eugene Parker was 91 years old.
帕克太阳探测器还有一个独特之处，即它是首个以在世人物命名的 NASA 航天器。2018 年 8 月发射时，物理学家尤金·帕克已 91 岁高龄。

But in the six years since the probe has been zipping through outer space and flying by the Sun? Not so much. Let's face it, the astrophysical properties of the Sun and its complicated structure are not something that most people think about on a daily basis.
但在探测器飞驰于外太空并掠过太阳的这六年里，情况并非如此。面对现实吧，太阳的天体物理特性和其复杂的结构并非大多数人日常会思考的问题。

However, the smallish probe—it masses less than a metric ton, and its scientific payload is only about 110 pounds (50 kg)—is about to make its star turn. Quite literally. On Christmas Eve, the Parker Solar Probe will make its closest approach yet to the Sun. It will come within just 3.8 million miles (6.1 million km) of the solar surface, flying into the solar atmosphere for the first time.
然而，这个小型探测器——其质量不足一公吨，科学载荷仅约 110 磅（50 公斤）——即将迎来它的闪耀时刻。确实如此。在圣诞前夜，帕克太阳探测器将实现迄今为止对太阳的最接近接触。它将飞至距太阳表面仅 380 万英里（610 万公里）处，首次进入太阳大气层。

Yeah, it's going to get pretty hot. Scientists estimate that the probe's heat shield will endure temperatures in excess of 2,500° Fahrenheit (1,371° C) on Christmas Eve, which is pretty much the polar opposite of the North Pole.
是的，温度将会变得相当高。科学家估计，在圣诞前夜，探测器的热屏蔽将承受超过 2,500 华氏度（1,371 摄氏度）的高温，这与北极的寒冷几乎完全相反。

Going straight to the source
直击源头

I spoke with the chief of science at NASA, Nicky Fox, to understand why the probe is being tortured so. Before moving to NASA headquarters, Fox was the project scientist for the Parker Solar Probe, and she explained that scientists really want to understand the origins of the solar wind.
我与美国宇航局科学部门主任尼基·福克斯进行了交谈，以了解为何要对探测器进行如此严苛的测试。在调任至美国宇航局总部之前，福克斯曾是帕克太阳探测器的项目科学家，她解释说，科学家们迫切希望了解太阳风的起源。

This is the stream of charged particles that emanate from the Sun's outermost layer, the corona. Scientists have been wondering about this particular mystery for longer than half a century, Fox explained.
这是从太阳最外层——日冕——发出的带电粒子流。福克斯解释说，科学家们对这个特殊谜团的思考已超过半个世纪。

"Quite simply, we want to find the birthplace of the solar wind," she said.
“简而言之，我们想要找到太阳风的诞生地，”她说。

Way back in the 1950s, before we had satellites or spacecraft to measure the Sun's properties, Parker predicted the existence of this solar wind. The scientific community was pretty skeptical about this idea—many ridiculed Parker, in fact—until the Mariner 2 mission started measuring the solar wind in 1962.
早在 20 世纪 50 年代，在我们拥有卫星或航天器来测量太阳属性之前，帕克就预言了这种太阳风的存在。科学界对此观点相当怀疑——事实上，许多人还嘲笑了帕克——直到 1962 年水手 2 号任务开始测量太阳风。

As the scientific community began to embrace Parker's theory, they wanted to know more about the solar wind, which is such a fundamental constituent of the entire Solar System. Although the solar wind is invisible to the naked eye, when you see an aurora on Earth, that's the solar wind interacting with Earth's magnetosphere in a particularly violent way.
随着科学界开始接受帕克的理论，他们渴望了解更多关于太阳风的知识，这是整个太阳系的基本组成部分。尽管肉眼看不见太阳风，但当你在地球上看到极光时，那就是太阳风以特别猛烈的方式与地球磁层相互作用的结果。

Only it is expensive to build a spacecraft that can get to the Sun. And really difficult, too.
只是建造一艘能到达太阳的航天器成本高昂，而且难度极大。

Now, you might naively think that it's the easiest thing in the world to send a spacecraft to the Sun. After all, it's this big and massive object in the sky, and it's got a huge gravitational field. Things should want to go there because of this attraction, and you ought to be able to toss any old thing into the sky, and it will go toward the Sun. The problem is that you don't actually want your spacecraft to fly into the Sun or be going so fast that it passes the Sun and keeps moving. So you've got to have a pretty powerful rocket to get your spacecraft in just the right orbit.
现在，你可能会天真地认为，向太阳发射航天器是世界上最简单的事情。毕竟，太阳是天空中如此巨大且质量庞大的天体，拥有强大的引力场。物体应该会因为这种引力而被吸引过去，你似乎可以随便把什么东西抛向空中，它就会朝太阳飞去。但问题是，你并不希望你的航天器真的飞入太阳，或者因为速度太快而掠过太阳继续前行。因此，你需要一个非常强大的火箭，才能将航天器送入恰到好处的轨道。

That’s a dynamic spacecraft
那是一艘动态航天器

And then you've got to have a pretty sophisticated spacecraft that can survive flying into the atmosphere of a star. Because it's super hot and there's this hellish radiation all around, not to mention plasma.
然后，你需要一个非常先进的航天器，它能够承受飞入恒星大气层的考验。因为那里超级热，周围充满了地狱般的辐射，更不用说等离子体了。

But you can't get around the fact that to observe the origin of the solar wind, you've got to get inside the corona. Fox explained that it's like trying to understand a forest by looking in from the outside. One actually needs to go into the forest and find a clearing. However, we can't really stay inside the forest very long—because it's on fire.
但无法回避的事实是，要观测太阳风的起源，就必须进入日冕内部。福克斯解释说，这就像试图通过从外部观察来理解一片森林。实际上，需要进入森林并找到一片空地。然而，我们无法在森林里停留太久——因为它正在燃烧。

So, the Parker Solar Probe had to be robust enough to get near the Sun and then back into the coldness of space. Therein lies another challenge. The spacecraft is going from this incredibly hot environment into a cold one and then back again multiple times.
因此，帕克太阳探测器必须足够坚固，以接近太阳并重返寒冷的太空。这又带来了一个挑战。探测器将在这极热与极冷的环境间多次往返。

"If you think about just heating and cooling any kind of material, they either go brittle and crumble, or they may go like elastic with a continual change of property," Fox said. "Obviously, with a spacecraft like this, you can't have it making a major property change. You also need something that's lightweight, and you need something that's durable."
“如果你考虑加热和冷却任何材料，它们要么会变脆而碎裂，要么可能会像弹性体一样，随着属性的持续变化而变形，”福克斯说。“显然，对于这样的航天器来说，你不能让它发生重大的属性变化。你还需要某种轻量且耐用的材料。”

The science instruments had to be hardened as well. As the probe flies into the Sun there's an instrument known as a Faraday cup that hangs out to measure ion and electron fluxes from the solar wind. Unique technologies were needed. The cup itself is made from sheets of Titanium-Zirconium-Molybdenum, with a melting point of about 4,260° Fahrenheit (2,349° C). Another challenge came from the electronic wiring, as normal cables would melt. So, a team at the Smithsonian Astrophysical Observatory grew sapphire crystal tubes in which to suspend the wiring, and made the wires from niobium.
科学仪器也必须得到强化。当探测器飞向太阳时，有一个被称为法拉第杯的仪器悬挂在外，用于测量来自太阳风的离子和电子通量。这需要独特的技术。法拉第杯本身由钛-锆-钼合金片制成，熔点约为 4,260 华氏度（2,349 摄氏度）。另一个挑战来自电子线路，因为普通电缆会熔化。因此，史密森天体物理观测台的一个团队培育了蓝宝石晶体管，用于悬挂线路，并将导线制作成铌材质。

Anyway, all that is to say, it took a lot of time, money, and technological breakthroughs in exotic materials to get a spacecraft that was up to the task. And on Christmas Eve, we're finally going to see what the Parker Solar Probe has got.
无论如何，这一切都说明，为了打造一艘能够胜任任务的航天器，我们投入了大量的时间、资金以及在特殊材料方面的技术突破。而在圣诞前夜，我们终于将一睹帕克太阳探测器的实力。

Eric Berger Senior Space Editor

Eric Berger Senior Space Editor
埃里克·伯杰高级太空编辑

Eric Berger is the senior space editor at Ars Technica, covering everything from astronomy to private space to NASA policy, and author of two books: Liftoff, about the rise of SpaceX; and Reentry, on the development of the Falcon 9 rocket and Dragon. A certified meteorologist, Eric lives in Houston.
埃里克·伯杰是 Ars Technica 的高级太空编辑，报道从天文学到私人航天再到 NASA 政策的所有内容，并著有两本书：《Liftoff》讲述了 SpaceX 的崛起；《Reentry》则探讨了 Falcon 9 火箭与 Dragon 飞船的发展历程。作为一名持证气象学家，埃里克居住在休斯顿。

135 Comments

Going straight to the source直击源头

That’s a dynamic spacecraft那是一艘动态航天器

Going straight to the source
直击源头

That’s a dynamic spacecraft
那是一艘动态航天器