Placeholder Image

Subtitles section Play video

  • - Last video, I was at the Ashton Graybiel Spatial Orientation Lab at Brandeis University,

  • and while I was there one of the team just casually mentioned

  • that they have an artificial gravity laboratory.

  • Artificial Gravity Facility sounds like something out of science fiction,

  • but it's not, and there's very much a reason why

  • I'm keeping my head straight and forward at the moment.

  • This is the Artificial Gravity Facility, otherwise known as the rotating room.

  • So, let's do some experiments.

  • This is unscripted. I don't know what's going to happen now,

  • other than things are going very weird when I move my arms.

  • Okay, so it's a room that rotates.

  • No one has invented science fiction gravity generators yet,

  • but if you have a theoretical spaceship going to Mars

  • and you wanted to generate apparent gravity

  • to keep astronauts healthy, that's what you'd do.

  • You would spin up the ship and use centrifugal force.

  • And that lab is the research prototype.

  • How do humans deal with a very strange gravitational environment?

  • - The first thing that you should do is try to push yourself off the wall

  • and align your body with the direction of the resultant.

  • - Oh. Oh, okay!

  • [laughter]

  • - Now you're standing upright.

  • - Wow. Can I walk, or is that gonna--

  • - No, don't walk, it's a little dangerous.

  • - It is almost impossible to envision

  • long duration space flight without artificial gravity.

  • The best way to study artificial gravity on Earth

  • is to build a rotating environment.

  • We started designing it in the mid-80s.

  • Ideally we want to study its effects on the human body

  • and we want to learn also how to pre-adapt astronauts

  • to the force of artificial gravity.

  • 99.9% of those will be highly dysfunctional individuals until adapted.

  • - They have NASA-standard sick bags for everyone, by the way.

  • I was required to keep one in my back pocket throughout just in case,

  • because if you tilt your head too fast

  • your inner ear has no idea what's going on and things go... wrong, very quickly.

  • - And now move your arm and try to go as straight as you can.

  • - [laughter]

  • Oh, I moved my head.

  • - You shouldn't move your head. - Do you get used to this?

  • - Yeah, yeah, you get used to it, yeah. You can adapt.

  • Move your arms and try to feel this force that is...

  • - Oh. That is...

  • Okay, just to be clear, I'm not putting this on,

  • as far as I'm concerned,

  • the signals I'm giving to my muscles are, 'move my arms forward'.

  • And now I'm forcing them.

  • But I'm pushing against a force here, you know.

  • - If you keep going, at some point you won't feel the force anymore.

  • - Oh that's weird.

  • - That's weird, right? - That's so weird.

  • - So now we are adapted.

  • - So if I try to do anything else, I haven't adjusted to it.

  • But that specific movement, my body's got used to.

  • - That's right. - Wow.

  • - One way to visualise this force

  • is for me to try and throw a little tennis ball at you.

  • I will throw it straight at you,

  • - Okay. - and see what happens, okay?

  • - Whoa!

  • What?

  • [laughter]

  • I'm struggling to work this out. Wh...

  • Because, in my head, this is a normal reference frame.

  • But it's clearly not. - We are rotating.

  • And now I'm gonna throw it over there.

  • - Yeah. - And hopefully

  • it's gonna get at you. - Okay.

  • - Are you ready?

  • - Yeah, throw it.

  • - Yes!

  • - Ah nice. - Great.

  • [laughter]

  • - Wow.

  • All those artefacts are from the Coriolis force.

  • It's not a real force acting on the ball, but it looks like one

  • when you're in that weird rotating environment.

  • Have a look at this 360° image of the lab.

  • Now, it's a little distorted because it's from a single camera in the middle,

  • but it's close enough. Here's the tricky part:

  • the circumference of a circle is longer the further out you go from the middle.

  • But because everything in that circle is rotating at the same speed,

  • once around every six seconds,

  • things on the outside have farther to travel, so they're

  • moving at a faster speed than things on the inside.

  • On the outside, we're moving pretty fast, but that camera in the middle

  • is just spinning on the spot.

  • So let's mark the sideways speed that everything

  • is moving at, relative to the rest of the world.

  • Green is fast, red is slow.

  • When you throw a ball across that room it keeps that

  • sideways speed that it had when it left your hand

  • as it travels into slower moving areas of the room.

  • Now, out at the edge, that was fine.

  • It was going the same speed as everything around it,

  • so it looked like it aimed for the centre.

  • But by the time it starts to get there, it's a missile,

  • flying outwards compared to everything around it.

  • Now from the outside that make sense.

  • After it leaves your hand, the ball

  • just moves in a straight line.

  • From the inside it looks like there's a force suddenly sending it sideways,

  • and that is the Coriolis force.

  • And it's not something your brain has evolved to deal with.

  • - Now, if you move your arms, you're pretty much fine.

  • - Oh! I...

  • [laughter]

  • - Just by moving around, you have been adapting.

  • - That's ridiculous. Thank you so so much.

  • I'm gonna throw this at you one more time, okay?

  • - Okay.

  • [laughter]

  • - The question that lab needs to answer is:

  • Can humans adapt to that over time?

  • And if so, how long does it take them to come back down to Earth?

  • Let's bring this to a stop!

  • Avi, can you bring us to zero?

  • Bring your hands down and don't move.

  • - I swear, the room is tilting--

  • - Don't move!

  • Oh, that's weird.

  • - And we're stopped, so try to swing your arms in front of you.

  • [laughter]

  • Oh, I don't like that.

  • - You've been adapted.

  • There are no unusual forces on your arms but

  • you feel it, right? - But they're still, yeah,

  • They're still doing that.

  • - And now you have to re-adapt.

  • - Thank you so, so much.

  • Thank you so much to everyone at the Ashton Graybiel

  • Spatial Orientation Lab at Brandeis University.

  • Pull down on the description for more about them and their work.

- Last video, I was at the Ashton Graybiel Spatial Orientation Lab at Brandeis University,

Subtitles and vocabulary

Click the word to look it up Click the word to find further inforamtion about it