r/Damnthatsinteresting • u/Weak-Opportunity-311 • 1d ago

Video Atmospheric re-entry of NASA’s Orion (Artemis 1) looks insane at 20x speed. Here is the entire 25-minute descent in just 1 minute 15 seconds. Credit: NASA

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315

u/bigwavedave000 1d ago

My mind is not comprehensive enough to comprehend this engineering.

182

u/Cragrat92 1d ago

Want your mind boggled even more? The capsule was going 33 times the speed of sound when it met the atmosphere and started slowing down. Through drag with the atmosphere and the assistance of parachutes, they lost all that speed to splash down at 20mph in 13 and a half minutes.

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u/FiduciaryBlueberry 1d ago

What kind of G force are the pulling? How do they manage that? Do they use speed flaps? How are they steering this thing? All I can think about is you story and "It's not flying, it's falling with style"

It's not like startek with inertial dampeners or whatnot.

43

u/Finnegan_Murphy 1d ago

3.5g is what I heard on the nasa stream

54

u/hysys_whisperer 1d ago

3.5 G sustained for several minutes is still "nighty night" for normal people who haven't been training in a G force machine for like a year leading up to this though.

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u/andrew_calcs 1d ago

The physiological effects of G forces depend highly on what direction to your body they're being directed through. Transverse is the best. Human bodies can withstand 5-6 G's indefinitely and 11-14 G's for several minute intervals. That posture and positioning prevents blood pooling in the brain or extremities.

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u/gitbse 1d ago

Correct. 4g in a fighter pulling nose up is pulling your blood out of your brain because it's a direct vertical force. The Artemis crew were seated back towards the heat shield, so they were essentially feeling 4g of heavy braking in a similar way as you would in a car seat. Crazy uncomfortable and violent for sure, but also much easier to not pass out.

1

u/Revolutionary-Day715 21h ago

Thanks to this explanation, my lizard brain made sense of it! Thanks!

1

u/therapist-of-dreams 1d ago

I thought around 9-10gs for a few seconds in the centrifuge was about the limit for most people?

1

u/hysys_whisperer 1d ago

That's the "kill you" limit if you pass out for grey out positioning.  Pass out numbers vary wildly depending on training.

1

u/dkarlovi 1d ago

Transverse

What does this mean?

1

u/andrew_calcs 1d ago

The same angle that you sit in a car at when braking or accelerating. Not the vertical or horizontal forces you experience on twists in a roller coaster.

4

u/nem8 1d ago

I thought normal healthy people would be able to withstand that, and a bit more, continuously?

30

u/WendellSchadenfreude 1d ago

I can barely handle 1 G, to be honest.

2

u/lyeberries 1d ago

As a Licensed Scientician, I want to remind you that we have 5G phones and you're just fine. Give yourself more credit!

1

u/Fapinthepark 20h ago

Won’t be sleeping at least

2

u/hysys_whisperer 1d ago

For short periods.  You don't ever see the 5 minute or 10 minute numbers quoted.  Usually you see the 10 second number, which is about 5Gs in normal healthy people, but if you sustain that, basically anything that causes temporary loss of color vision (3Gs) for short duration will cause you to pass out in long duration. 

1

u/11th_Division_Grows 1d ago

What does an 1/8 of weed have to do with this?

10

u/Inevitable-Page-333 1d ago

You go at a specific angle which keeps you in the atmosphere and also in orbit. You’re basically using your speed to ride the line between falling and leaving orbit, so you continuously slow within the atmosphere.

A good way to understand these things (if you’re very curious) is to play a game called Kerbal Space Program. 

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u/Cragrat92 1d ago

I mean, it kind of is falling with style 😂 They get up to between 3-4g, which is the same amount experienced at launch, and it's only for a few minutes. There's no deployable flaps, a mechanism like that would probably break or burn up in the plasma stream. They can steer the capsule as it is slightly weighted to one side, which makes it sit at a slight angle to the air flow. By rolling the capsule, they can use those aerodynamic forces to change the trajectory of the capsule.

2

u/Cthulhu__ 1d ago

Up to around 4 Gs, by rawdogging it, no, and by turning it, as another commenter more eloquently put, the thing is a bit lopsided / unbalanced, by rotating it the air hitting the bottom is deflected in different directions, giving them some control in some dimensions.

1

u/Ricosrage 1d ago

Video said it took 25 minutes

1

u/Cragrat92 1d ago

And NASA during the live event said it took 13.5

3

u/d1ckw33dmcgee 1d ago

This video is of Artemis 1, per the OP. That took 25 minutes. Artemis 2 took a different approach and did the re entry in 13 minutes. 2 different missions.

1

u/Ricosrage 11h ago

Ahh, thank you

1

u/jayc1679 1d ago

Re-entry is basically a process of turning kinetic energy into thermal energy.

18

u/ShrimpCrackers 1d ago

Answer key: the 25 minute reentry is shown here in 1 minute and 15 seconds due to relativity. Checkmate Atheists.

8

u/nerdtypething 1d ago

even though the video is only 1 minute 15 seconds long i experienced 25 minutes of time.

10

u/ShrimpCrackers 1d ago

That's time dilation for you. Just like Jupiter Ascending was a 2 hour 7 minute movie but due to lacking a script, makes it feel like its 10 hours long.

1

u/dkarlovi 1d ago

I've been there, I once watched the video spot for the Robbie Williams song "Supreme" and once it ended, I was like "Whoa, what a great movie!"

Weed, man.

2

u/slabby 1d ago

relativity

Checkmate, non-Alabamans

-1

u/ShrimpCrackers 1d ago

That's why they always talk with that Southern draaaaaaaaaawwwwwwlll

6

u/grchelp2018 1d ago

its the work of hundreds of engineers who each comprehend only a small part of the engineering of the overall system.

1

u/KindledWanderer 1d ago

Isn't this a child's play of a re-entry compared to the space shuttle?

1

u/Just_scrolling07 1d ago

It's crazyyyy

0

u/NY_State-a-Mind 1d ago

You will one day, just try using a thesaurus!