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 happen much - the EMUs are heavy.
Extravehicular Mobility Unit
Systems Training Workbook
This picture of a Manipulator Foot Restraint - ...
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 formally known as a Valsalva device (used by both astronauts and divers for equalizing pressure in their sinuses. (Thanks to Organic Marble's comment).
In addition, ...
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 of water, the flow is obstructed which means it takes energy to push the water around.
you're replacing the air layer (which is a reasonably good thermal ...
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 thoroughly debunks the idea, noting that:
Gagarin was not in "critical condition" after his flight; and,
Any flights in LEO are well within Earth's magnetic field.
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 obvious way to distinguish the two suits. After that stripes were added to the commander's suit for the remaining Apollo missions.
As far as I'm aware, the ...
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 the world outside the space suit, came
a muted, sporadic tinkling sound, the result of minor collisions
between our drifting tools and the airlock walls.
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 visor. The clear protective visor is a
sacrificial shield that protects the pressurized bubble from any wear
and tear or dents and scratches from the abrasive ...
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 each EVA (Extravehicular Activity).
Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/...
From this question on Physics.SE:
But other than that, there is no reason why a man couldn't be lobbed from behind Jupiter, make a slow-down loop around the Moon, then spiral down to Earth... given some marvelous suit that will withstand the atmospheric entry.
From this question on Felix Baumgartner:
Note that even if he jumped from "infinity", ...
A space suit could be tested to double 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 essential.
To allow enough flexibility, the pressure difference (inside to outside) should be not greater than 0.2 to 0.4 bar. Breathing pure oxygen in the suit at ...
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 various technical debrief documents. The problem tended to arise from the fact that the gloves are pressurised, therefore stiff.
The journal also links to a ...
Without a glove, a space suit would basically lose its integrity. It is like not wearing a suit in the first place. Then, the question is what happens next.
The closest known resemblance of such a scenario happened during a test of an Apollo space suit in a vacuum chamber:
(In 1965, a tube pressurising a space suit of a ...
...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 put them in danger.
This happened to ESA astronaut Luca Parmitano when doing a space walk at the ISS. See Space.com's Italian Astronaut Recounts Near-Drowning ...
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.
Breathing air is supplied via an umbilical and bouyancy weigh-outs are added to the exterior of the suit.
So: the soft goods (arms, legs, gloves, boots), the helmet, ...
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 were a concern; this is one of the reasons all of the Apollo landings took place within 12 to 48 hours after sunrise at the landing site. The lunar surface wasn'...
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 trace chemical contaminants generated from material off-gassing and crew metabolic functions remain within allowable limits. A mass spectrometer measures the ...
There is space for two full Extravehicular Mobility Units (EMUs), one short EMU, and two Orlan space suits (Russian equivalent to the EMU) aboard the ISS. They are stored in the Joint Airlock. Since the spacesuits are not part of the emergency plan, they do not store one for every astronaut (let alone a backup for each).
Answer by Robert Frost, ...
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 design a suit without any motors, and it may even have been done, but pumps, blowers and valves and such seem a sort of natural feature of a space craft life support ...
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 for patent, especially when the port was eliminated. Hamilton Standard is listed as government employee on the patent form.
The patent can be found in NTRS ...
The atmospheric pressure on Mars is about 0.6% of Earth's sea level pressure. That's about 0.6 kilopascals (0.087 psi). Whereas even one of the highest points on earth, Mount Everest is 33.7 kilopascals (4.89 psi). That means Mount Everest has about 56 times the atmospheric pressure of the surface of Mars.
Humans wouldn't survive very long in those ...
The biggest issue was that the source of the liquid wasn't established and that it might have not been safe to drink, potentially causing bigger problems than Luca immediately faced. He did try to drink a bit of the fluid, and reported that it has an odd taste, so it was not his drinking water. They opted for immediate retreat back to the Quest airlock and ...
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 noise interference and selectivity to voice. For many decades, the ДЭМШ-microphone was installed in almost all Soviet military and professional civilian radio ...
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 attached oxygen hoses from the
Lunar Module (both inlet and outlet) while at the same time attaching
to the inlet and outlet hoses of the portable backpack. ...
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 quite some time (2-3 hours no nose or butt scratching) and it wasn't really a problem.
Also, if you're concentrated on something serious (like doing work in a ...
The US's only "modern, real" space suit, the Extravehicular Mobility Unit (EMU), was designed in the 1970s. It has a very limited sensor suite and no automation at all.
The only sensors used in the suit are
A biomedical harness (with electrocardiograph electrodes)
A carbon dioxide (CO2) partial pressure sensor
A total pressure sensor
ventilation flow ...
The serial numbers of the Apollo spacesuits are documented on this NASA webpage.
Each astronaut was assigned three suits for a particular mission: a Flight Suit, worn only during the mission; a Back-Up Suit; and a Training Suit. Some suits did double duty, most usually when an astronaut moved from a Back-Up crew to Primary crew for a later mission. The ...
Shuttle crewmembers wore a g-suit, but only for entry.
Crewmembers wear a g-suit for entry that provides pressure to the lower body separate
from the ACES. The applied pressure prevents blood from pooling in the lower
extremities upon return to 1-g conditions after two or more days of microgravity.
Crewmembers wearing the ACES suit do not ...
You are referring to the materials protecting from insulation and the outer layers of space suits. Look carefully, they have not seen much change since the Apollo era.
In Mercury, the suits were still at an rather early stage of development. They were intended as pressure-suits protecting the astronauts from decompression in case there was a leak in the ...
While Rory's answer is close, let me give a few additional details.
The orbital speed is about 7.8 km/s in low Earth Orbit.
If you are orbiting, you will not fall straight down. It just won't happen. In fact, the maximum speed would result from a minimal burn, which would take you through the atmosphere quite slowly.
You will start slowing down to an extent ...