ฝึกพูดภาษาอังกฤษด้วยเทคนิค Shadowing จากวิดีโอ: What If We Moved All 8 Billion People To Mars?

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269 ประโยค
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War?
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Environmental destruction?
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Global warming?
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Species extinction?
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Spaceship Earth is being trashed by its crew.
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It's looking like humanity.
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It needs a plan B.
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Fast.
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And the obvious candidate?
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Well, it's staring down at us every night.
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Mars.
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It has a total surface area almost equal to Earth's entire land area.
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So there's room for all of us.
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And unbelievably large sums of money are being directed to space exploration.
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So it's not so out there to ask, what if we moved all 8 billion of us humans to Mars?
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When you measure it, Earth is 71% ocean.
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The livable area we live on is just a small part of the total.
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So even though Mars is a planet with roughly half the diameter of Earth,
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its livable surface area is strikingly similar to what we have on Earth.
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So Mars has room for us.
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Now, the most important element to sustain human life is water.
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Wherever we move to, we're going to need lots of water.
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And Mars may look like a dry rock, but unlike closer destinations like the Moon,
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it secretly has water, and plenty of it.
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Water on Mars exists as ice at the poles, or it's hidden in deep rock formations beneath the surface.
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The scientists have estimated that there's enough subsurface water on Mars to cover the entire planet one to two kilometers deep.
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Now, the next thing we'll need is air to breathe.
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And Mars has air.
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It's thin compared to Earth, but Mars has an atmosphere and weather systems to go along with it.
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Currently, the air can't sustain human life without a space suit, but it is something to build on.
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And given the choices of other close-by options, Mars is much better than the completely airless Moon,
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or our closest neighborhood planet, Venus, where the atmosphere is mostly carbon dioxide and sulfuric acid.
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It also has a surface temperature of a blistering 464 degrees Celsius.
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That's 867 degrees Fahrenheit.
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And an atmospheric pressure 93 times that of Earth.
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So when you look at the hellscape that's Venus, Mars is pleasantly inviting.
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And then there's light.
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Wherever we go, we're going to need some sunlight.
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Mars is only one and a half times the distance from the Sun as Earth is, so it's only a little farther away.
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At that distance, Mars might seem like a cold environment compared to Earth, but it's close enough to the Sun to receive a useful amount of sunlight
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that can be turned into solar power and to grow crops.
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And Mars has seasons, like on Earth.
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Mars' longer orbit means it takes longer to go around the Sun, so a Martian year is longer, at 687 Earth days.
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But it has a similar rotation to Earth.
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A day on Mars lasts 24.6 hours, compared to our 23.9.
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Plus, it has a very similar axial tilt of 25 degrees, compared to Earth's 23.4 degrees.
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And wherever we move to needs to be as close as possible.
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There are closer destinations than Mars, like Venus or Mercury, but by any measure, they're completely unlivable.
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So we're left with Mars as our closest habitable option.
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Now, the Red Planet is the only logical next step after the Moon, which itself is an unimaginably harsh environment.
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It's fit only as a launching pad to space.
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The Moon is a great stepping stone to other places, maybe a small colony, but certainly not for 8 billion of us.
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So Mars looks very promising.
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And colonizing Mars isn't just wild speculation.
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The race to Mars has already begun.
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We're about to see one of the most technically ambitious and well-resourced space programs in human history shift into high gear.
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The financial markets are already going there.
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Just look at the valuation of SpaceX in 2026, which came in around $1.7 trillion.
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Compare that with the operational budget of NASA's entire 13-year Apollo project in the 60s.
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That cost around $300 billion, adjusted for inflation.
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That shows that this is by far the most well-funded space project in human history, by a multiple of five.
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This is getting real, real fast.
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There's no question Earth is dying and Mars has space, Mars has water, Mars has an atmosphere and sunlight.
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It's relatively nearby and we've already got remote rovers exploring it.
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And one of the most valuable companies in the world is throwing all its capital and resources into getting there.
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All that's left is to get all 8 billion of us off Earth and onto Mars.
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So how many humans have we put into space so far?
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10,000?
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Maybe 1,000?
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Nope, 781.
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Not exactly an inspiring start.
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SpaceX is leading the charge right now, constantly wrapping up its launch schedule.
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But even with all that effort, the numbers are still tiny.
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The SpaceX managed 96 launches in 2023, upping it to 134 launches in 2024,
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and hit an all-time high of 165 launches in 2025, which was their busiest year ever.
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But most of those launches have been without human passengers.
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Of the 781 people who have left Earth and touched space, SpaceX has only lifted 78 of them.
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Its Dragon spacecraft took six years and 20 different missions to get to that number, too.
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That's the entire track record of the most active rocket company on Earth, set against our target of 8 billion people.
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In the short human history of space travel, the single best year on record put about 70 people into space,
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which was a record set by a combination of NASA and other countries during the peak of the space shuttle program.
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And that was back in 1985.
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Now, the record for the most people in space at the same time was set much more recently, in 2023.
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And that record was tied again in 2024 when, drumroll please, Eleven people were on the International Space Station,
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three on China's Tiangong Space Station, and six were aboard Virgin Galactic's VSS Unity space plane,
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which spent only part of its hour-long flight in suborbital space.
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So the record is 20 people, and it lasted less than an hour.
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Humans establishing a permanent presence in orbit is an incredible achievement, and more are on their way,
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but we're talking about evacuating Earth's entire population.
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So how difficult is this really going to be?
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SpaceX's most favorable projections for its Starship have a goal between 100 and 200 passengers per launch.
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For argument's sake, let's be incredibly generous.
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Elon loves to plan big and go even bigger, so let's give him the benefit of the doubt and multiply the high end of those numbers by 10.
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So every launch would have 2,000 passengers.
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Well, even at that accelerated rate, you'd need 4 million launches to move 8 billion people.
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Okay, let's frame this from the perspective of a human lifespan,
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not some abstract future, but as a project that someone born today has a chance of seeing reach completion.
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At 4 million launches spread across a century of continuous non-stop launching,
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that works out to about 110 launches of 2,000 person starships every single day for 100 years straight.
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Put that beside the actual record, SpaceX's busiest year ever was about 165 launches.
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Moving everyone within a century means sustaining roughly 240 times that annual rate.
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Not for one record-setting year, but for every single year, 100 years straight.
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And there's a huge complication to this scenario.
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They can't launch every day.
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Because Mars and Earth are moving in relation to one another, they only line up for an efficient journey every 26 months.
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So launches can't be spread out.
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They need to be crammed into the 46 or so windows of opportunity that occurred during that 100-year period.
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Okay, well, that would be 87,777 launches during those precious windows and a standing fleet of ships ready to go,
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numbering in the tens of thousands.
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Now, if we were to dial back this hypothetical fantasy
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and use the number of ships that Elon Musk himself floated as an eventual goal of SpaceX,
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a fleet of 1,000 ships carrying 100 passengers each, launching during the windows of opportunity,
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well, the job would take 173,300 years.
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we're definitely going to need a bigger lifeboat.
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Let's take our number and multiply it by 100, a measure of scale that's way beyond our current thinking,
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but also still inside the bubble of what's conceivably possible.
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Let's imagine that we can build ships that could carry 20,000 people per launch, a design that has no real engineering behind it.
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But to get a sense of this scale, think of the world's largest cruise ship, Royal Caribbean's icon of the seas.
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It's 365 meters long.
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That's 1,200 feet long, longer than three football fields.
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And it weighs 250,000 gross tons.
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Between the crew and the passengers, it holds about 10,000 people.
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So double that, stand it on end and shoot it into space.
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Even at this gargantuan size, we would need 400,000 launches to get everyone off Earth.
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That's 11 launches a day for a century.
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And again, you can't launch every day.
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Even carrying 20,000 passengers each trip, the size of the fleet would still need to be enormous.
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A quick trip to Mars, given current technology, would take 200 days one way, a 400 days round trip,
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with no time for turnaround.
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But the ship that went to Mars would have to wait there for a window of opportunity to return to Earth,
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so they wouldn't get back in time for the next launch window 26 months later.
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We'd have to maintain a fleet double the amount.
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That's 17,390 ships to keep to this launch schedule.
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And here's the kicker.
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Even if we start with a static base figure of 8 billion people, that figure is going to rise daily.
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To make it simple, let's say we stick with the wildly optimistic figure of 11 launches of 20,000 people a day.
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So that's 220,000 people a day leaving Earth.
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But there are approximately 360,000 births a day on Earth and about 160,000 deaths for a daily population gain of around 200,000.
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To get everyone off Earth and to safety, we'd have to launch a minimum of 10 ships with 20,000 people on them every day
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before we even started to evacuate any of the waiting 8 billion people alive today.
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And all this is without getting into the mind-numbing cost of lifting that much tonnage into space.
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The per kilogram cost of energy spent to send payloads into space is just the start.
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Humans need incredibly complex life support equipment, food and waste management systems.
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So unless we build a fleet of thousands of gigantic ships
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and focus all of humanity's resources on this project for over a century, we won't be moving to Mars.
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Elon Musk's aspiration is for a 1 million person city on Mars within 20 to 30 years.
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Even if we ran the numbers for a fraction of Earth's population, say 8 million, and we went back to the most optimistic numbers floated by Elon,
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we would be looking at between 40,000 and 80,000 launches.
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But the math we're dealing with is for 1,000 times that population.
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But let's say human engineering, labor, and resource allocation all rise to the occasion,
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and humanity pulls together and commits to this project for a century, and we move the human population of Earth to Mars.
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What happens next?
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How do we survive?
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Okay, the problem with Mars is that when you shine a critical light on it, and look past the surface comparisons,
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It has none of the basics we humans need to survive.
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If you think Earth's resources are stretched thin, well, let's take a look at a planet that has virtually nothing to offer.
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The water on Mars is trapped in ice, the air is almost non-existent,
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there's no food source, the dust that covers the planet is toxic, radiation levels are sky-high, and the sunlight is weak.
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When it gets down to the simple facts, Mars is going to try and kill you over and over and over again.
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All that subsurface water is buried so deep that it's almost impossible to get to.
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Drilling a hole 10 km deep on Earth would be an engineering feat in and of itself.
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The air is too thin to breathe, so you need to wear a space suit at all times when outside.
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Even if you could go outside without a suit, the fine toxic dust that covers every inch of the planet will poison you.
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And even then, the planet doesn't have a global magnetic field blocking out radiation like Earth does.
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So the radiation bathing you is 100 times Earth's natural background level.
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Without protection, it will slowly and inevitably destroy your cells.
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So you need to be shielded more or less permanently.
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Plus, this barren planet would starve you.
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This would be the equivalent of having 8 billion people live in a submarine.
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Permanently.
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Never surfacing.
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Sound like fun?
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Well, there's more.
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Let's take a closer look at what kind of resources we'd need to survive on Mars.
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There's a parallel right here on Earth on Earth, the harsh, unforgiving conditions in Antarctic research stations.
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Nearly everything for human survival there is shipped in from outside.
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780 kilograms of food per person per year needs to be imported for the crew.
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The state-of-the-art experimental mobile greenhouse Eden ISS,
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built to grow food for crews on space stations grew 268
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kilos of food over about 286 days for a crew of 10, working out to about 27 kilos per person,
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roughly 3.4% of the 780 kilos a person actually eats every year.
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Almost all of these stations' operational energy needs to be imported too.
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Powered by diesel generators, the fuel is shipped in by boat and then flown in by plane.
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Locally generated wind power covers only about a fifth of the two stations' needs.
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The South Pole station runs on a lean few hundred kilowatts of power on average to support up to 150 people,
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but it still burns about 1.7 million liters of fuel a year.
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scale up this Antarctic math for 8 billion people, and stretch the supply line across 54.6 million kilometers,
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and the numbers start looking impossible.
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Nothing grows naturally on Mars.
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There's no viable soil, other than what Matt Damon might have left up there.
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And you can't just add water to the dust that's on the ground, it's dead.
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Every single calorie of food would have to be shipped in or grown in artificial greenhouses with imported soil.
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Feeding everyone on Mars at the Antarctic per person rate would require 6.24 trillion kilograms,
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or 6.24 billion tons of food every year.
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An amount that grown indoors at the best Eden ISS greenhouse yield ever achieved would need a sealed,
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artificially lit farm about the size of the United Kingdom.
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The power for lighting and heat alone for 8 billion people on Mars, even at bare research station rates per person,
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comes out to roughly 9 times all the electricity humanity currently generates worldwide.
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On a planet that receives less than half of Earth's sunlight, is prone to planet-wide dust storms, and has no natural fuel reserves.
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And building up an industrial base in the long term on Mars would have severe challenges.
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The simple fundamentals like no hydrocarbons for plastics,
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and no coking coal for conventional steel would leave Mars lacking industrial basics.
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Due to a lack of critical resources,
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Mars would never be able to sustain some of the simple industrial chains that are essential to our modern technological world.
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Not to mention the very complex technological chains that drive Earth's current economy and tech industry.
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Semiconductor supply chains that only a handful of Earth's most advanced economies manage would be almost impossible on a planet like Mars.
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Mars would likely remain highly dependent on Earth for many of the survival-level basics for centuries, and maybe forever.
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And unlike colonies of the past on Earth, Mars wouldn't be a source of new wealth for the colonial home country,
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but an incredible resource drain.
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In the case of a dying Earth, the resources expended on the Mars project would only speed up our decline.
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The most radical fix would be to terraform the entire planet, transforming the dry, barren rock that is Mars into a fertile,
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green water world like Earth.
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But this process, even if it was possible, would take unimaginable resources and hundreds,
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if not thousands, of years to achieve.
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But let's say we did it.
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Humanity pulled together all its resources and achieved the unachievable.
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And we moved all eight billion of us to Mars and we solved the problems of water, radiation, dust, food, and energy supply.
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Well, we still have a bigger problem.
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The problem is us.
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Because who's to say that the same 8 billion people who trashed Earth wouldn't do the same thing on Mars?
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Humans have reshaped Earth.
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We now live in the Anthropocene, a new geological epoch defined by human activity on Earth.
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We've changed the composition of the atmosphere.
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Atmospheric carbon dioxide is now 50% higher than it was before the Industrial Revolution.
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The ocean has absorbed enough carbon dioxide to increase its acidity by 30%.
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44% of Earth's habitable land has been turned into agricultural land.
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Humans have wiped out 60% of the planet's mammals, birds, fish and reptiles since 1970.
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In the past decades, these human impacts have accelerated at an unprecedented rate.
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Sometimes referred to as the Great Acceleration, we're increasing carbon dioxide emissions,
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ramping up global warming, speeding up ocean acidification, destroying habitats faster, killing off more species,
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and doubling down on natural resource extraction.
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This is our track record.
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This is what 8 billion humans are capable of.
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And there's no indication that we wouldn't just do the same thing again on a new planet.
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Same population, but in an even more fragile situation.
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It's hard to imagine how humanity will act living in an almost entirely artificial closed-in world on Mars.
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But given the evidence, the citizens of Mars are likely to exploit, deplete, degrade their home in the same way they did on Earth.
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To add to this, the fact
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that every colony a country has ever established has eventually turned away from its colonizer and fought for independence.
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many times violently.
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Just like when the American colonies turned against Britain,
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the interests of the Mars colony would eventually drift out of alignment with whatever political entity was left on Earth.
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But in this case, even a resource depleted
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and environmentally degraded Earth would still look like a green paradise compared to the harsh, barren surface of Mars.
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Even a half-dead Earth probably recovering after the exodus of humans, would be a strong temptation to a struggling Mars colony.
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Which leads us to the real deal.
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Any problem that's big enough to make us seriously consider fleeing the planet
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is far cheaper to fix here than to restart from nothing on Mars.
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That's a summary of Neil deGrasse Tyson's point of view on the matter.
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Neil, who is the director of the Hayden Planetarium, aka someone who really, really knows space.
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The harsh fact is that there is no plan B.
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But if we understand this profound truth, we might just have a chance.
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If we turned the resources we're currently committing to financial fantasies toward the real world problems we face,
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we wouldn't have to leave Earth.
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Ironically, the global cooperation needed to plan and pull off mass immigration to Mars
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would be exactly the international coming together we'd need to move towards sustainability and to reverse Earth's decline.
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Fixing our problems here is far more realistic and achievable than escaping to space.
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But there is one external existential threat that we can't fix by ourselves here on Earth.
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It's happened before, and we probably won't be able to do anything about it.
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That's a direct hit by an asteroid that could render Earth completely uninhabitable.
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Even a small asteroid impact could scramble the global climate and send our complex and fragile civilization back to the Stone Age.
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We might be able to deflect or destroy an approaching asteroid threat if we had enough early warning,
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but there's also a chance we don't see it coming in time.
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This is not a fantasy situation.
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One of these asteroids has already ended an entire era of life.
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But when the Chicxulub asteroid smashed into Earth, it changed the climate overnight,
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wiped out the dinosaurs, and redirected the trajectory of evolution.
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But that's a story for another WHAT IF.
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Transcription by CastingWords

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ช่องเดียวกัน

FOR YOU

วิดีโอแนะนำ

คำศัพท์และข้อสังเกตด้านการพูดสำหรับบทเรียนนี้

บทเรียนฝึกพูดระดับ B2 นี้ใช้วิดีโอ “What If We Moved All 8 Billion People To Mars?” เป็นสื่อ คำที่ถูกพูดซ้ำบ่อยที่สุด: Mars, Earth, space, planet, billion วิดีโอนี้มี 268 ประโยค และ 3358 คำ สำหรับฝึกพูดตาม ช่วงที่มีเสียงพูดยาว 26:43 ผู้พูดพูดด้วยความเร็วสม่ำเสมอ ประมาณ 126 คำต่อนาที เหมาะกับการฝึกพูดตาม มีเพียง 81% ของคำที่อยู่ใน 3,000 คำที่ใช้บ่อยที่สุดในภาษาอังกฤษ คำศัพท์จึงค่อนข้างยาก

คำศัพท์สำคัญในวิดีโอนี้

คำที่ยากที่สุด 15 คำในวิดีโอ พร้อมคำอ่านและความหมาย:

คำศัพท์คำอ่านความหมาย
sunlight คำนาม/ˈsʌnˌlaɪt/แดด, แสงอาทิตย์
asteroid คำนาม/ˈæst(ə)ɹɔɪd/ดาวเคราะห์น้อย
barren คำคุณศัพท์/ˈbæɹən/เป็นหมัน
import คำนาม/ˈɪm.pɔɹt/การนำเข้า
kilogram คำนาม/ˈkɪləɡɹæm/กิโลกรัม, กิโล
multiply คำกริยา/ˈmʌltɪplaɪ/คูณ
accelerate คำกริยา/ɪkˈsɛl.əˌɹeɪt/เร่ง
greenhouse คำนาม/ˈɡɹːnˌ(h)aʊs/เรือนกระจก
fragile คำคุณศัพท์/ˈfɹæd͡ʒəl/บอบบาง
optimistic คำคุณศัพท์/ˌɒptɪˈmɪstɪk/มองโลกในแง่ดี
wipe คำกริยา/waɪp/เช็ด
orbit คำนาม/ˈɔɹ.bɪt/วงโคจร
mathematics คำนาม/mæθ(.ə)ˈmæt.ɪks/คณิตศาสตร์
absorb คำกริยา/æbˈsɔɹb/ดูดซับ
bury คำกริยา/ˈbɛɹi/ฝัง

ประโยคที่ควรฝึกพูดซ้ำ

ประโยคสั้น ๆ ที่สมบูรณ์จากวิดีโอ ซึ่งนำไปใช้ในบทสนทนาประจำวันได้:

  • Wherever we go, we're going to need some sunlight.
  • For argument's sake, let's be incredibly generous.
  • We'd have to maintain a fleet double the amount.
  • How do we survive?
  • We've changed the composition of the atmosphere.

ไวยากรณ์ในวิดีโอนี้

โครงสร้างที่ผู้พูดใช้บ่อยที่สุด พร้อมคำพูดจริงจากวิดีโอ:

โครงสร้างในวิดีโอ
Present perfect have/has + กริยาช่อง 3 — เหตุการณ์ในอดีตที่ยังเกี่ยวข้องกับปัจจุบันhave estimated · has already begun · have been
Passive voice be + กริยาช่อง 3 — เน้นสิ่งที่เกิดขึ้น ไม่ใช่ผู้กระทำbeing trashed · being directed · can be turned
Relative clauses who / which + อนุประโยค — ข้อมูลเพิ่มเติมเกี่ยวกับคนหรือสิ่งของpeople who have · people who trashed · someone who really

การออกเสียงที่ควรระวัง

ผู้พูดใช้รูปย่อและรูปลดเสียง 34 ครั้ง เช่น we're, can't, wouldn't ให้พูดแบบสั้นตามที่ได้ยิน

  • เสียง “sh” และ “zh”: harsh /ˈhɑɹʃ/, emission /ɪˈmɪʃ.ən/, shuttle /ˈʃʌtəl/, ambitious /æmˈbɪʃ.əs/, fraction /ˈfɹæk.ʃən/
  • คำยาว — ลงเสียงหนักให้ถูกพยางค์: habitable /ˈhæbɪtəbəl/, accelerate /ɪkˈsɛl.əˌɹeɪt/, atmospheric /ˌætməsˈfɛɹɪk/, optimistic /ˌɒptɪˈmɪstɪk/, technological /ˌtɛk.nəˈlɑ.dʒɪ.kəl/

เสียงที่คนไทยมักออกเสียงยาก:

  • เสียงท้ายคำ — ออกเสียงให้ครบ ไม่เปลี่ยนเป็นตัวสะกดแบบไทย: harsh /ˈhɑɹʃ/, habitable /ˈhæbɪtəbəl/, greenhouse /ˈɡɹːnˌ(h)aʊs/, fragile /ˈfɹæd͡ʒəl/, technological /ˌtɛk.nəˈlɑ.dʒɪ.kəl/
  • /v/ — ไม่ใช่ /w/ ให้ฟันบนแตะริมฝีปากล่าง: favourable /ˈfeɪv(ə)ɹəbəl/, inevitably /ɪˈnɛvɪtəbli/, viable /ˈvaɪəbəl/, civilization /ˌsɪv.ɪ.laɪˈzeɪ.ʃən/, overnight /əʊvə(ɹ)ˈnaɪt/
  • /z/ — เสียงก้อง ไม่ใช่ /s/: civilization /ˌsɪv.ɪ.laɪˈzeɪ.ʃən/, poison /ˈpɔɪ.zən/

วิธีฝึกกับวิดีโอนี้

  1. ฟังวิดีโอให้จบหนึ่งรอบโดยยังไม่ต้องพูด แล้วจดคำที่ยังไม่รู้จัก
  2. พูดตามทีละประโยคด้วยความเร็วปกติ ทำซ้ำแต่ละประโยคจนจังหวะของคุณตรงกับผู้พูด
  3. อัดเสียงตัวเองแล้วเทียบกับต้นฉบับ โดยสังเกตคำอย่าง sunlight, asteroid, barren เป็นพิเศษ

เทคนิค Shadowing คืออะไร?

Shadowing เป็นเทคนิคการเรียนรู้ภาษาที่ได้รับการรับรองทางวิทยาศาสตร์ พัฒนาขึ้นสำหรับการฝึกนักแปลมืออาชีพ วิธีการนี้เรียบง่ายแต่ทรงพลัง: คุณฟังเสียงภาษาอังกฤษจากเจ้าของภาษาและพูดตามทันที — เหมือนเงาที่ตามผู้พูดด้วยช่วงเวลาห่าง 1-2 วินาที การวิจัยแสดงว่าเทคนิคนี้ปรับปรุงความแม่นยำในการออกเสียง ทำนองเสียง จังหวะ การเชื่อมเสียง การฟังเข้าใจ และความคล่องแคล่วในการพูดได้อย่างมีนัยสำคัญ

เทคนิค shadowing: อ่านคู่มือฉบับเต็มทีละขั้นตอน →