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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.

  • Which is why NASA is developing a nuclear-powered rotorcraft-lander, deemed Dragonfly, to send

  • to Titan's surface.

  • This car-sized drone will investigate the organic-rich terrain like never before, revealing

  • whether or not this moon really is a “primordial earth”,

  • harboring the very beginnings of life.

  • The reason we know anything at all about the composition of Titan, is thanks to the European

  • Space Agency's Huygens probe and NASA's Cassini spacecraft.

  • After disembarking from Cassini, the Huygens probe had a hazardous two and a half-hour

  • descent to the moon's surfacecollecting data as it went.

  • 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.

  • Titan has an atmosphere, winds, dry river beds and lakes, mysterious dunes, a possible

  • subsurface ocean, cryovolcanoes, and, most excitingly, key ingredients for life, like

  • methane, ethane propylene, nitrogen, and carbon.

  • It was these qualities that propelled the creation of the Dragonfly mission.

  • Dragonfly is led by a team out of John Hopkins University, but it was an international collaboration

  • to get the unique duel quadcopter design, and for good reason.

  • So why is everyone excited about this mission?

  • Well, traditional crafts, such as a lander or rover, are limited to their immediate location.

  • A rover couldn't quickly travel vast expanses and a lander doesn't move at all.

  • But scientists found that Titan's cold atmosphere, and predominantly nitrogen makeup provides

  • a lower molecular viscosity than Earth's.

  • This, paired with high densities means it's much easier to get heavier items off the ground,

  • like a car-sized drone.

  • Plus, decades worth of advancements of autonomous multirotor technology made a rotorcraft a

  • perfect deep space candidate.

  • Scientists estimate Dragonfly will fly orhopfrom one location to the next faster

  • than any Mars rover has driven in a decade.

  • Over the course of two years, Dragonfly will have accumulated over a hundred and seventy

  • kilometers of groundwork, and it's prepared to do so, with a robust suite of instruments.

  • Looking under the hood, the drone will be equipped with a Multi-Mission Radioisotope

  • Thermoelectric Generator, better known as its nuclear power.

  • This same system has been used before to power the Mars Curiosity rover.

  • MMRTG's work by converting heat from the natural decay of radioisotope materials, in

  • this case plutonium-238.

  • It then uses solid-state thermocouples to convert the heat energy from that decay into

  • electricity.

  • What makes this latest engineering design special is that it generates smaller increments

  • of electricity, about 110 watts at launch, which will help prolong its lifetime in space.

  • Plus, the MMRTG will power a battery that is roughly a quarter of the size of those

  • found in a Tesla electric vehicles.

  • And Dragonfly's innovations don't stop there.

  • The rest of the craft will be composed of highly-specialized instruments that will be

  • used to explore the complex terrain on Titan.

  • These will include, geophysical and meteorological sensors, cameras to look ahead at horizons

  • and pointed below to look at dunes. And when it lands, Dragonfly will have an underbelly

  • instrument that will fire neutrons at the surface and and look for any gamma rays released

  • to determine terrain types, like ammonia-rich ice or carbon-rich sand dunes.

  • With all that's ahead, it's almost no surprise that the Dragonfly team won NASA's

  • competition, the New Frontiers Program.

  • Previous winners of this program include innovations like OSIRIS-REx, JUNO, and the New Horizons

  • spacecraft.

  • NASA considers this competition to represent a critical step in the advancement of solar

  • system exploration.

  • Dragonfly plans to launch in 2026 and arrive at Titan in 2034, and once it does, we'll

  • be one step closer to answering the questions to if life is only unique to our planet.

  • If you haven't already noticed, Seeker's Countdown to Launch series has gotten a facelift!

  • And that's because we're committed to bringing you more launch coverage than ever

  • before.

  • And with all the exciting missions we've done in the past and have planned for the

  • future, we want to know which ones do you want to hear about?

  • Let us know in the comments below.

  • Also, check out our CTL playlist that features stories on the latest launches from SpaceX

  • and ISRO.

  • Don't forget to subscribe so you never miss an episode.

  • Thanks for watching and we'll see you next time on Seeker.

Saturn's largest moon, Titan, is thought to have seas of methane with a landscape and

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美國宇航局的核動力無人機將在土衛六上搜索生命。 (NASA’s Nuclear Drone Will Search for Life on Titan)

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    林宜悉 發佈於 2021 年 01 月 14 日
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