79
votes
Accepted
Why do astronauts wear heels?
That only looks like a heel! As shown here, it's a "foot restraint interface"!
That said, it probably makes walking around in the training facilities a lot easier. Although that doesn't ...
- 178k
75
votes
Accepted
How do astronauts on EVA deal with nose itching?
According to Chris Hadfield's answer during his Reddit AMA:
"We have a squishy thing inside we jam our nose into while we clear our ears — we scratch our nose on that."
The "squishy thing" is ...
- 4,350
64
votes
Why do astronauts wear spacesuits during launch?
Are there failure modes that cause loss of pressure but not rapid, unplanned disassembly?
Yes.
The 3-man crew of Soyuz 11 died when a valve was jolted open, venting out all the cabin air supply. ...
- 167k
56
votes
Accepted
Why aren't spacecraft and spacesuits pressurised to 2.5 psi (17 kPa) of pure oxygen?
The sum of all partial pressures in the lungs must add up to the ambient pressure.
The composition of gas inside the lungs includes the vapor pressure of H₂O at body temperature which is about 0.9 psi....
- 17.6k
51
votes
instead of pressurizing an entire spacesuit with oxygen could oxygen just pressurize the head and the rest of the body be pressurized with water?
There's no advantage to replacing the air with water.
you're adding weight.
you're adding resistance: when you move around, water will flow around the body and because you're proposing a thin layer ...
- 126k
50
votes
Have any space suits (not) used "pulsed magnetic devices"?
Spacecraft and space suits do NOT generate a magnetic field for medical reasons. Any magnetic fields generated are side effects of using electric motors etc.
The linked question on Skeptics ...
- 126k
50
votes
Accepted
How do ISS astronauts "get their stripes"?
They're simply visual differences for identification.
After Apollo 11, folks on the ground had a hard time finding photos of Armstrong on the moon. Most photos were taken by him and there was no ...
- 6,667
49
votes
Accepted
What is the text on Neil Armstrong's space suit's left glove?
It's called, appropriately enough, the "sewn-on cuff checklist".
Aldrin's tasks are in parentheses as shown by the (LMP) annotation at the top.
It's a checklist of pretty much everything ...
- 178k
41
votes
Accepted
What sounds do astronauts hear inside their helmets during an EVA?
Tom Jones talks about it some in his memoir "Skywalking" when he describes an EVA carried out on shuttle mission STS-98:
Inside the airlock when it is pressurized
Through the helmet shell, from ...
- 178k
39
votes
Accepted
What are the Advantages of having a Double-pane Space Helmet?
The outer pane is just a replaceable protection of the inner pane against scratches, dirt, and abrasion.
The helmet on the suits for Artemis missions will also feature a
quick-swap protective ...
- 48.8k
33
votes
Would a duct tape spacesuit be practical?
If the suit would be useful, it has to be inflated. Which is definitively not how it looks like in images. If you could manage duct tape to hold the inner pressure for a moment without rupturing and/...
- 1,831
33
votes
Accepted
How was the "female" SK-2 different from the "male" SK-1 spacesuit?
The SK-2 suit differed from the SK-1 suit mainly in the enclosure cut-out that took into account the specific features of a female body. The enclosure featured a decreased shoulder breadth, an ...
- 2,143
31
votes
How do EVA suits manage water excretion?
The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after ...
- 178k
30
votes
Accepted
What does "double vacuum pressure" mean in space-suit testing?
A space suit could be tested to double the operating pressure. This test can be done in a vacuum or in air. For the stability of the suit, only the pressure difference between inside and outside is ...
- 48.8k
28
votes
Accepted
Astronauts make a lot of CH₄ and some H₂ as well; do space capsules and space stations have systems to remove these?
For the ISS, the relevant bit of kit would be the Trace Contaminant Control System, which is part of the Air Revitalisation System.
A Trace Contaminant Control System ensures that over 200 various ...
- 8,001
28
votes
Why is there a white panel in astronaut’s fabric headcover they wear inside the hard helmet?
This is called a Snoopy Cap.
It's a hood that holds the communications headset to the astronaut's head.
The white portion is elastic fabric to make the cap fit snugly; the black portions are a non-...
- 8,627
27
votes
Accepted
Do Astronauts lose finger nails in space?
They tended to suffer painful fingernails in the Apollo days, in the Lunar Surface Journal Schmitt and Cernan gave a good description of this on several pages. There were also references made in the ...
- 5,178
26
votes
instead of pressurizing an entire spacesuit with oxygen could oxygen just pressurize the head and the rest of the body be pressurized with water?
...a thin layer of water that was held down by oxygen up at the head.
"Held down" doesn't work so well in weightlessness. Water would move around inside the suit, climb up the astronaut's neck and ...
- 149k
26
votes
Where exactly are the Apollo space suit sublimators venting steam into space? is there a photo of an astronaut in space that shows the opening?
It can be hard to see because it's on the front of the PLSS behind the astronaut's helmet.
(NASA photo of Irwin on Apollo 15, I cropped it and added the arrow)
Here's an exploded view showing the ...
- 178k
26
votes
Accepted
Why is the new Artemis suit orange?
Same reason the shuttle ACES suit was orange. Both were to be worn during launch and reentry, when contingencies are possible that would put a crew member in the ocean. The color aids visibility for ...
- 6,667
25
votes
Accepted
Are the EVA suits used in the ISS and in the NBL same or different?
The suits used in the NBL are Class III "training only".
The Display and Control Module (control panel on the chest), the life support backpack, and the SAFER self-rescue unit are mocked-up.
...
- 178k
23
votes
How do astronauts on EVA deal with nose itching?
From Retro Space Images's FaceBook post:
Gene Cernan scratches the itch during an Apollo 17 training session at KSC.
- 677
23
votes
Accepted
How do space suits offer heat protection i.e. during the lunar day?
I didn't know that during lunar day temperature is up to +100°C.
That's how hot the lunar surface can get at the equator, about 2/3 of the way into the 2 week long lunar day. Those high temperatures ...
- 73.2k
23
votes
In simple terms, how does the way space suits manage breathable gas differ from how scuba gear does it?
Intravehicular spacesuits are worn inside the cabin in case of emergencies, particularly during ascent and descent. The Mercury suits were manufactured by Goodrich. Nearly all other IV suits have ...
- 47.7k
22
votes
Have any space suits (not) used "pulsed magnetic devices"?
Well, an electric motor is arguably a 'pulsed magnetic device', as is a solenoid valve, but good ones try very hard to contain the fields to where they will do useful work.
I suppose one could ...
- 401
21
votes
Accepted
What was the space helmet "vomit port"?
I think the device in question is described in US Patent 3,437,165 "VENTING DEVICE FOR PRESSURIZED SPACE SUIT HELMET" (filed Feb 27, 1967). It is possible that NASA did not file immediately ...
- 6,906
20
votes
Accepted
Why don't astronaut helmets fog up? What's the chemistry and thermodynamics behind keeping the field of view clear even during heavy breathing?
Dry, incoming air is blown across the inner surface of the visor from a part called a "spray bar". Thin-film heaters and chemical agents have also been used, to less success.
Although water ...
- 47.7k
19
votes
Accepted
What are these objects near the Cosmonaut's faces?
These are two microphones of the cosmonaut's headset (шлемофон - hat with headphones and microphones). Two microphones reserve each other.
The ДЭМШ-microphone possessed considerable resistance to ...
- 7,813
19
votes
Accepted
Why did the hose connectors on Apollo spacesuits come in pairs?
From History of the Apollo Space Suit by the International Latex Corporation (ILC). PDF
When setting up the suits in preparation for the extravehicular walk
on the lunar surface, the astronauts ...
- 48.8k
18
votes
How do astronauts on EVA deal with nose itching?
How about Willpower? Every Soldier learns to stand still at a parade or when they got to pledge loyalty. When I had my inauguration at the Austrian Military forces, we all had to stand still for ...
- 197
Only top scored, non community-wiki answers of a minimum length are eligible