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  • Ever had a freshly cooked steak, delivered

  • straight from the International Space Station?

  • Let me tell youit's not

  • going to be what you expect.

  • You must have so many questions right now.

  • Salad or mashed potatoes?

  • It's not every day that a chunk of meat falls from the sky.

  • Astronauts on the International Space Station

  • have precautions in place to keep

  • anything from dropping down to Earth.

  • But at the same time, they have to deal with

  • spacesuit gloves that only allow about

  • 20% of their gloveless range of motion.

  • And sometimes, things do slip away.

  • Astronauts have dropped everything

  • from a camera to a spatula.

  • They used that thing for space shuttle repairs and

  • not for cooking, in case you're wondering.

  • What if you got to go the ISS,

  • and on your final spacewalk,

  • a perfect cut of rib eye steak

  • slipped through your hands,

  • completely by accident?

  • Before we get to the part where you're spacewalking

  • with a piece of raw meat in your hands,

  • we need to figure out how to

  • get that meat there in the first place.

  • The International Space Station has been

  • continuously occupied since the end of the year 2000.

  • But none of its visitors have been chefs.

  • Astronauts have all their food precooked here on Earth.

  • Their meals either come ready to eat,

  • or can be easily prepared adding water

  • or by heating.

  • Anything that hadn't been approved

  • six months before your launch

  • would be prohibited.

  • You would break about 20 food regulations

  • by sneaking raw meat aboard the ISS,

  • let alone by dropping that meat from orbit.

  • There is a reason why dropping objects

  • from the Space Station is a no-go,

  • and requires astronauts to report

  • such incidents immediately.

  • But let me go back to it in a moment.

  • The ISS is orbiting 400 km (248 mi) above the Earth.

  • What do you say, we start the experiment

  • with some closer-to-Earth cooking?

  • As a side note, I'll eliminate

  • some of the orbital effects from the story.

  • For now.

  • Let's imagine that the steak you dropped

  • would head straight down to the ground.

  • When an item, like a steak,

  • is plummeting to Earth from space,

  • it moves really fast.

  • And because of that high speed,

  • the air in front of it can't get out of the way fast enough.

  • It gets compressed.

  • And when air is compressed, its molecules

  • move faster, releasing kinetic energy.

  • Things get hotter.

  • But would it get hot enough to fry the steak?

  • Let's see.

  • If you dropped the steak from a height of 70 km (43 mi),

  • it would break the sound barrier.

  • For about a minute, the air around it

  • would heat up to 177 °C (350 °F).

  • If you've ever cooked steak, you know that

  • this time and temperature isn't quite enough

  • to cook the meat all the way through.

  • When the steak hits the ground,

  • it would still be far from well-done.

  • At 100 km (62 mi) up, your rib eye

  • would be falling at twice the speed of sound for 90 seconds.

  • That's enough to add a little cooked

  • crispness to its surface.

  • Unfortunately, you'd still be eating raw steak,

  • thanks to the sub-zero temperatures

  • of the Earth's stratosphere.

  • Dropping a steak down from

  • 250 km (155 mi) above Earth

  • would get it that lovely seared surface.

  • The falling meat would travel at

  • six times the speed of sound,

  • although it would still end up raw on the inside.

  • If the steak fell from even higher above the atmosphere,

  • its front shockwave would have temperatures

  • reaching thousands of degrees.

  • The meat's surface layer would start to burn off,

  • looking more like flakes of carbon

  • rather than a nice, medium-rare steak.

  • But even dropping the steak from the ISS

  • wouldn't give it enough time to cook through.

  • You'd be eating a burned lump of protein

  • that's raw red in the center.

  • On Earth, it actually takes some

  • degree of talent to cook a steak like that,

  • if you take away the burning part.

  • Space makes for a horrible barbecue

  • unless you prefer your steak raw

  • with an ashy aftertaste.

  • You'd also have to wait quite some time

  • for a steak to reach your plate.

  • If the ISS itself were to fall from space,

  • it would take 2.5 years due to the orbit it's in.

  • Exactly how long it would take a steak to free fall

  • from a height of 400 km (248 mi) is uncertain.

  • In reality, if we turn the orbital forces back on,

  • your steak wouldn't actually make it to Earth.

  • Your potential dinner would go into orbit first.

  • Then, roughly 90 minutes later,

  • it would be flying right back at the ISS

  • at a speed of roughly 28,000 km/h (17,500 mph).

  • It might not hit the ISS, but

  • if it did, you'd know it right away.

  • Red meat is bad enough for you on Earth, but

  • in space, it has the potential

  • to wipe out an entire crew.

  • If you're still up for the experiment,

  • at least remember to sterilize the meat

  • before you seal it in a pouch.

  • And don't take cabbage, beans

  • or broccoli for a side dish.

  • Those foods make astronauts fart.

  • And that's never a good thing in close quarters.

  • The only escape from that stinky situation

  • would be taking a walk in outer space,

  • maybe, with no spacesuit at all.

  • But that's a story for another WHAT IF.

Ever had a freshly cooked steak, delivered

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如果你從軌道上掉下一塊牛排怎麼辦? (What If You Dropped a Steak From Orbit?)

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    林宜悉 發佈於 2021 年 01 月 14 日
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