Placeholder Image

字幕列表 影片播放

  • [ ♪ Intro ]

  • Do you want to live a strong, happy life on Mars?

  • Well, drink red wine.

  • At least, that's what a lot of recent headlines will have you believe.

  • Those articles are talking about a study published last week in Frontiers in Physiology,

  • which found that a compound in red wine could help prevent muscle atrophy on the Red Planet.

  • Except, they're also a bit misleading.

  • For one thing, the study didn't actually use wine.

  • It used supplements of a chemical compound called resveratrol,

  • which happens to be in red wine, along with things like blueberries.

  • Also, the scientists didn't test their hypothesis on humans, but on rats.

  • So for now, these results are worth taking with a bit of a grain of salt.

  • But that does not mean they aren't important.

  • When you hear people talk about living on Mars,

  • they often mention challenges like the planet's cold temperatures, or lack of breathable air.

  • But this study was trying to tackle another major obstacle: Mars's gravity.

  • Since it's about sixty percent lower than Earth's,

  • explorers on Mars wouldn't have to exert their bodies as much,

  • so their bone strength and muscle mass would decline.

  • It wouldn't be as extreme as what would happen during their multi-month trip to Mars,

  • where they'd feel completely weightless.

  • But since these people could very well be spending the rest of their lives on that planet,

  • scientists have already started looking for solutions.

  • That is where this pilot study comes in.

  • The work was conducted by scientists at Harvard Medical School,

  • and they performed their tests on twenty-four 14-week-old, male rats.

  • Half of the animals were allowed to roam their cages as normal,

  • and the other half had to move around while being suspended by cute, little, tiny rat harnesses.

  • This mimicked the amount of gravity they'd experience on Mars.

  • Half of each group then got a daily dose of resveratrol dissolved in sugar water,

  • 150 milligrams per kilogram of body weight.

  • Other than that, everybody ate the same diet.

  • Over the course of the two-week experiment, researchers measured the size of the rats' calves,

  • as well as the grip strength of their front and rear paws.

  • Then, after the two weeks had passed, the rats were euthanized so their tricep muscles

  • could be studied in greater detail.

  • After all the data was analyzed, scientists found that

  • the resveratrol didn't completely protect the rats in harnesses from muscle atrophy,

  • but it did appear to prevent some of it.

  • The rats in this group even had a grip strength comparable to the animals in the control condition:

  • those who didn't live in a harness or get any resveratrol.

  • The supplement also appeared to help the harnessed rats maintain the same muscle composition.

  • Previous studies like this have demonstrated that micro-gravity actually causes some muscles fibers

  • to switch from slow-twitch to fast-twitch.

  • In other words, they switch from a type that provides endurance

  • to a type that's good for quick bursts of effort.

  • A change like this would make a Martian colonist tire out way more quickly,

  • which isn't something you'd want for such a harsh lifestyle.

  • So it's promising that resveratrol could maybe help prevent that.

  • As for why resveratrol might be having this positive effect,

  • it may have something to do with the fact that the compound has been shown to increase the body's sensitivity

  • to insulin.

  • Insulin signals your muscle cells to take in glucose, which they need to work and stay healthy.

  • So increased insulin sensitivity could make this process extra effective.

  • Alternatively, resveratrol could have an anti-inflammatory effect that helps conserve muscle and bone cells.

  • It's still too early to reach any conclusions.

  • Because, again, this was a proof-of-concept study.

  • The authors even acknowledged that it has a lot of limitations, like how all the rats were male,

  • and how they only tested one specific dose of resveratrol.

  • So this phenomenon hasn't even been fully investigated in rodents,

  • let alone attempted in humans.

  • And if you look in the literature, well,

  • many results found in mice or rats don't translate to us, especially in nutrition studies.

  • This means we're nowhere near, like, prescribing red wine to astronauts.

  • But it does show that scientists are hard at work trying to figure these problems out.

  • Meanwhile, other researchers are trying to address those more planet-wide challenges:

  • things like how Mars's average temperature is -63 degrees Celsius,

  • and how its air pressure is too low to support liquid water on the surface.

  • All kinds of solutions have been proposed to fix these problems,

  • including an especially extreme terraforming.

  • This would be where we somehow transform Mars into, like, Earth 2.0.

  • Unfortunately, with our current technology and Mars's resources,

  • terraforming the whole planet doesn't seem possible.

  • But new research does suggest that we could potentially terraform a small part of it.

  • In a paper published last week in Nature Astronomy,

  • scientists suggested we could do this by building a dome

  • out of one of the weirdest materials humans have created: aerogels.

  • Aerogels are sometimes referred to asfrozen smoke,”

  • and they're a class of really cool-looking compounds that can be as much as 99% air.

  • They are gels, but the liquid part has been removed, leaving a solid, dry framework with

  • a bunch of air-filled pockets.

  • These compounds can be used for all sorts of things, including as fillers in cosmetics.

  • But this paper suggested that they'd be especially useful for terraforming a part of Mars.

  • For this kind of project, you'd need to build a dome out of something that traps heat,

  • lets light in for photosynthesis, and blocks ultraviolet radiation that could damage DNA.

  • And according to this paper, a thin shield of aerogel would do the job.

  • In this research, the team focused on translucent silica aerogels,

  • which have actually been used on Mars rovers for insulation.

  • The team experimented with both bead-like aerogel particles as well as large tiles,

  • shining light on them that mimicked what hits the Martian surface.

  • And they found that tiles 2 to 3 centimeters thick created a greenhouse effect

  • that raised surface temperatures beneath them by more than 50 degrees Celsius.

  • At mid-latitudes on Mars, that's about what you need to reach the melting point of water.

  • The tiles were likely so effective because air is an awesomely good insulator.

  • But that isn't the only thing this study found.

  • The silica aerogel also reduced the intensity of long-wavelength ultraviolet rays and blocked

  • nearly all of the more dangerous short-wave ones.

  • So, aerogels could potentially make for a great habitat.

  • And as a bonus, they're also incredibly light because of all the air they contain.

  • So taking a bunch to Mars wouldn't cost nearly as much

  • as sending something like concrete or steel.

  • But then again, we're still a long way from building terraforming domes.

  • And even this design isn't perfect: It wouldn't help us make Mars's atmosphere breathable,

  • and there's always the chance it could get covered in dust and block out sunlight.

  • But studies like this one and the one about resveratrol are still significant,

  • because they're setting the stage for future research.

  • So when the day does come that we're thinking of sending people to live on Mars,

  • we'll be prepared.

  • Thanks for watching this episode of SciShow Space News!

  • If you enjoy learning about things like this and want to show off your love for the universe,

  • we have a thing!

  • Every month to celebrate a different space mission in our history

  • we are going to be doing a limited edition pin.

  • The first one is of the Apollo 11 command and service module and it comes in two colors,

  • one of which is glow in the dark.

  • They're both the same price, why wouldn't you get the glow in the dark one?

  • It's available now and only until the end of July, so if you want it, now is your time!

  • In August, we'll be releasing a new space-themed pin.

  • I'm excited about that one too because I know what it is already, even though you don't.

  • You can them at dftba.com, or on our brand new merch shelf right below this video.

  • Isn't that neat?

  • [ ♪ Outro ]

[ ♪ Intro ]

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B1 中級

火星上生活的祕密。葡萄酒和氣凝膠?| 科學秀新聞 (The Secrets to Living on Mars: Wine and Aerogel? | SciShow News)

  • 12 0
    林宜悉 發佈於 2021 年 01 月 14 日
影片單字