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  • When it comes to landing spacecraft on planets, or moons, or back here on earthMars sucks.

    對於登陸行星、衛星或地球而言,火星真的很糟糕。

  • There's a lower success rate landing on Mars than on Venus, the moon, the earth, even

    登陸火星的成功率比金星、月球、地球、

  • Saturn's moon Titan.

    甚至土星的衛星泰坦都要低(才登陸一次是要比三小)。

  • And in large part, this is because Mars's atmosphere is in the perfect goldilocks zone

    主要是因為火星大氣層剛剛好處於

  • of being a total headache.

    最棘手的區間。

  • On the moon (or an asteroid) you can use lightweight spacecraft made essentially out of tinfoil

    在月球(或小行星)上,你可以用外殼輕薄的太空船登陸

  • because there's no air to cause drag or pressure or heat.

    因為沒有空氣就不會造成曳力、壓力或熱。

  • Essentially, you save weight not having heat shields or thick walls, but need to use rockets

    於是你不需要隔熱罩或厚重外殼,但需要用火箭

  • to land in what's called a “powered descent.”

    緩衝降落,稱為「動力降落」。

  • On earth, or Venus, or Titan, there's enough air that you can land largely unpowered, first

    在地球、金星或泰坦上, 有足夠的大氣層讓你充分減速,

  • by slowing down with a heat shield and atmospheric drag, and then with parachutes.

    先用隔熱罩和大氣層的阻力,再用降落傘減速。

  • So you use a lot of weight for heat shields and walls and parachutes, but don't need

    於是你需要很重的隔熱罩、外殼和降落傘,但不用

  • big rockets or lots of fuel to land.

    攜帶巨大的火箭和很多燃料。

  • However, the air on Mars is literally the worst of both worldsthick enough that

    但火星大氣卻比光譜兩端還要糟糕─它厚到

  • you actually have to deal with it with heat shields and walls, but thin enough that it

    讓你必須處理隔熱罩和外殼,又薄得無法

  • doesn't help you slow down much and you also need to use rockets.

    充分減速,讓你仍然得使用火箭。

  • Mars is simply a challenging place to land a spacecraft, which is why we've tried so

    火星對太空船登陸而言是個大挑戰,所以我們

  • many different and crazy techniques for landing there: we've landed landers and rovers using

    用了各種不同的瘋狂點子來登陸:包括

  • retrorockets, in inflatable bouncy airbags, by being lowered from a hovering sky crane

    逆噴射火箭、彈性氣囊、用空中起重機懸停垂吊......

  • all of which ALSO used heat shields and parachutes and rocket powered descent before

    這些方法在著陸的最後階段前,

  • the last stage of landing.

    仍得搭配隔熱罩、降落傘和動力降落。

  • And space agencies are testing other crazy things like giant supersonic parachutes and

    太空機構還在測試其他技術,例如巨大的超音速降落傘

  • inflatable innertubes around landers to increase their surface area and help them slow down

    或在登陸器周圍加裝彈性內胎,增加其表面積

  • more in the thin air before landing (probably still with rockets, or sky cranes).

    以便在稀薄的大氣層中更有效減速。 (可能還是要用到火箭,或空中起重機)

  • Yes, you heard that rightit's possible that when the first humans land on Mars, we

    是的你沒聽錯─也許第一個太空人上火星時,

  • may do so in an inflatable donut.

    他會待在一個充氣甜甜圈裡。

  • Or we'll just skim at a really low angle past the tops of mountains for a really long

    或者用極低的角度不斷掠過山頂,

  • time to slow down enough...

    慢慢減速......

When it comes to landing spacecraft on planets, or moons, or back here on earthMars sucks.

對於登陸行星、衛星或地球而言,火星真的很糟糕。

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