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Saturn’s largest moon, Titan, is thought to have seas of methane with a landscape and atmosphere functioning much similar to our own.
据说，土星最大的卫星泰坦星上不仅存在多个液态甲烷海洋，其地貌和大气的运转与我们的星球也非常相似。
Which is why NASA is developing a nuclear-powered rotorcraft-lander, deemed Dragonfly, to send to Titan’s surface.
宇航局着手开发一种准备发射到泰坦星表面的核动力旋翼着陆器“蜻蜓”的原因就在于此。
This car-sized drone will investigate the organic-rich terrain like never before,
这架汽车大小的无人机将以前所未有的方式探索该天体上富含有机物的区域，
revealing whether or not this moon really is a “primordial earth”, harboring the very beginnings of life.
揭示该卫星是否孕育生命起源，是否真为一个“原始态的地球”。
The reason we know anything at all about the composition of Titan,
我们能对泰坦星的组成产生一知半解，
is thanks to the European Space Agency's Huygens probe and NASA’s Cassini spacecraft.
则多亏欧洲航天局的“惠更斯号”探测器和美国宇航局的“卡西尼号”宇宙飞船。
After disembarking from Cassini, the Huygens probe had a hazardous two and a half-hour descent to the moon’s surface – collecting data as it went.
从卡西尼号脱落后，惠更斯号探测器历时两个半小时才降落到这一卫星表面收集数据，过程堪称十分惊险。
It was the first time scientists ever landed on a world in our outer solar system and the details from this mission provided a few insights.
这是科学家首次在太阳系的外层星球上着陆，任务的细节也进一步打开了我们的眼界。
Titan has an atmosphere, winds, dry river beds and lakes, mysterious dunes, a possible subsurface ocean, cryovolcanoes,
泰坦有大气层，风，有干涸的河床和湖泊，还有神秘的沙丘，可能还有地下海，低温火山，
and, most excitingly, key ingredients for life, like methane, ethane propylene, nitrogen, and carbon.
最令人兴奋的是，上面还有生命的关键成分——甲烷、乙烷丙烯、氮和碳等物质。
It was these qualities that propelled the creation of the Dragonfly mission.
正是这些特点推动了“蜻蜓计划”的诞生。
Dragonfly is led by a team out of John Hopkins University,
主持该计划的是约翰霍普金斯大学的一个团队，
but it was an international collaboration to get the unique duel quadcopter design, and for good reason.
但这是一个国际合作项目，旨在实现独特的双四轴飞行器的设计，合作是有充分的理由的。
So why is everyone excited about this mission?
那么问题来了，所有人都特别期待这次任务，这又是为什么呢？
Well, traditional crafts, such as a lander or rover, are limited to their immediate location.
原来啊，传统的飞行器，比如着陆器啊，月球车啊，都受到了直接位置的限制。
A rover couldn’t quickly travel vast expanses and a lander doesn’t move at all.
月球车无法快速穿越很远的距离，着陆器甚至完全动不了。
But scientists found that Titan’s cold atmosphere, and predominantly nitrogen makeup provides a lower molecular viscosity than Earth's.
然而，科学家们发现，泰坦星上有低温大气层，氮的主要组成能够提供比地球更低的分子粘度。
This, paired with high densities means it’s much easier to get heavier items off the ground, like a car-sized drone.
加上高密度，这就意味着，让沉重的东西，比如一架汽车大小的无人机，从泰坦星表面上飞起来要比在地球上容易得多。
Plus, decades worth of advancements of autonomous multirotor technology made a rotorcraft a perfect deep space candidate.
再者，数十年来，自主多旋翼技术一直在进步，旋翼飞行器已经成为深空飞行领域的最佳“人选”。
Scientists estimate Dragonfly will fly or “hop” from one location to the next faster than any Mars rover has driven in a decade.
据科学家估计，蜻蜓飞行器从一个地方飞到另一个地方的速度，将超过十年来任何一种火星探测车的速度。
Over the course of two years, Dragonfly will have accumulated over a hundred and seventy kilometers of groundwork,
按计划，在一套强劲的装备的加持下，
and it’s prepared to do so, with a robust suite of instruments.
届时，为期两年的时间，蜻蜓号将跨越170公里的范围。
Looking under the hood, the drone will be equipped with a Multi-Mission Radioisotope Thermoelectric Generator, better known as its nuclear power.
引擎盖下方的位置将配备一个多用途的放射性同位素热电发电机(MMRTG)，也就是传说中该飞行器的核动力部分。
This same system has been used before to power the Mars Curiosity rover.
在此之前，该系统曾用于驱动“火星好奇号”探测器。
MMRTG’s work by converting heat from the natural decay of radioisotope materials, in this case plutonium-238.
MMRTG的工作原理是将放射性同位素材料，在本案中就是钚238，自然衰变时产生的热量转化为热能。
It then uses solid-state thermocouples to convert the heat energy from that decay into electricity.
再用固态的热电偶将衰变产生的热能转化为电能。
What makes this latest engineering design special is that it generates smaller increments of electricity,
这项最新的工程设计的特别之处在于它产生的电力增量更小，
about 110 watts at launch, which will help prolong its lifetime in space.
发射时才110瓦左右，因而有助于延长飞行器在太空中的寿命。
Plus, the MMRTG will power a battery that is roughly a quarter of the size of those found in a Tesla electric vehicles.
此外，MMRTG将为约为特斯拉电动汽车电池四分之一大小的一块电池供电。
And Dragonfly’s innovations don’t stop there.
蜻蜓的创新点还不止于此。
The rest of the craft will be composed of highly-specialized instruments that will be used to explore the complex terrain on Titan.
飞船的其余部分将由高度专业化，可用于探索泰坦上复杂的地形的仪器组成。
These will include, geophysical and meteorological sensors, cameras to look ahead at horizons and pointed below to look at dunes.
如地球物理传感器和气象传感器，既可以仰望地平线也可以俯瞰沙丘的摄像机等。
And when it lands, Dragonfly will have an underbelly instrument that will fire neutrons at the surface
着陆后，蜻蜓飞行器腹部的装置能够发射中子，
and look for any gamma rays released to determine terrain types, like ammonia-rich ice or carbon-rich sand dunes.
通过检测卫星上的伽马射线来确定地形类型是富含氨的冰层还是富含碳的沙丘。
With all that’s ahead, it’s almost no surprise that the Dragonfly team won NASA’s competition, the New Frontiers Program.
有这些设计加持，“蜻蜓”团队能够赢得美国宇航局的“新边疆计划”竞赛一点也不奇怪。
Previous winners of this program include innovations like OSIRIS-REx, JUNO, and the New Horizons spacecraft.
在此之前，获得该竞赛的项目有奥西里斯-雷克斯计划、朱诺计划和新视野计划等。
NASA considers this competition to represent a critical step in the advancement of solar system exploration.
在宇航局眼中，这一比赛代表着太阳系探索进程中的关键进展。
Dragonfly plans to launch in 2026 and arrive at Titan in 2034,
蜻蜓飞行器计划于2026年发射，2034年到达泰坦星，
and once it does, we’ll be one step closer to answering the questions to if life is only unique to our planet.
届时，我们就离回答生命是否只存在于地球这一问题又近了一步。
If you haven’t already noticed, Seeker’s Countdown to Launch series has gotten a facelift!
如果你还没注意到，我们“发射倒计时”系列的节目已经改进啦。
And that’s because we’re committed to bringing you more launch coverage than ever before.
因为我们希望给大家带来比以往任何时候都多的有关航天发射方面的节目。
And with all the exciting missions we’ve done in the past and have planned for the future,
无论是过去那些激动人心的航天任务，还是已经规划的未来项目，
we want to know which ones do you want to hear about?
我们想知道，你们想了解哪些项目？
Let us know in the comments below.
快在下面的评论中告诉我们吧。
Also, check out our CTL playlist that features stories on the latest launches from SpaceX and ISRO.
还有，快去查看我们的CTL播放列表，了解SpaceX和ISRO的最新发射项目吧。
Don’t forget to subscribe so you never miss an episode.
别忘了订阅，以免错过任何一集新内容噢。
Thanks for watching and we’ll see you next time on Seeker.
感谢大家的收看，我们下期节目再见。
