132
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Could Apollo astronauts stand up if they fell on the moon?
I believe it was John Young, during an Apollo 16 EVA fell to the lunar surface. Though awkward, he got up unassisted by attempting a series of what looks like push-ups until he was able to get ...
- 7,029
79
votes
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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 ...
- 189k
59
votes
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Assuming a spacecraft is traveling in a constant rate and our Astronaut will exit it to a space walk, will she be "left behind" by the spacecraft?
As long as neither spacecraft nor the astronaut are accelerating or decelerating, the relative speed of the spacecraft and the astronaut remains the same. So the astronaut will hover near the ...
- 12.6k
58
votes
Could Apollo astronauts stand up if they fell on the moon?
As always, the Apollo Lunar Surface Journal is a treasure trove of annotated examples. During the later (J) missions in particular, Ed Fendell, remotely operating the rover's TV camera, managed to ...
- 1,805
41
votes
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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 ...
- 189k
39
votes
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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 ...
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35
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Assuming a spacecraft is traveling in a constant rate and our Astronaut will exit it to a space walk, will she be "left behind" by the spacecraft?
It turns out that outer space is not a perfect vacuum: there are a few hydrogen atoms per cubic centimeter. (reference)
For large X, non-relativistic physics, the astronaut and spacecraft will stay ...
- 421
33
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Is it really a "space walk" (EVA proper) if you don't get your feet wet (in space)?
Who do you consider an authority on the definition of EVA?
NASA performed so-called "stand-up EVAs" - head outside the craft, feet inside - during the Gemini program (e.g. Gemini 10, Gemini ...
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32
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Could Apollo astronauts stand up if they fell on the moon?
Despite Charlie Duke's concern about it, given that the PLSS is massive, and would shift an astronaut's center of gravity far back from their natural distribution, it would be surprising if the ...
- 172k
31
votes
Are there any plans for handling people floating away during an EVA?
A nitrogen cold jet thruster system called SAFER (Simplified Aid For EVA Rescue) is part of the US EVA suit ensemble. If a crewperson gets loose they can fly back using SAFER.
(Image source)
SAFER ...
- 189k
31
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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 ...
- 189k
30
votes
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Apollo command module space walk?
They did. Apollo 15, 16, and 17 has an EVA to recover film from cameras in the Scientific Instrument Module Bay (SIMBay) on the Service Module to bring back inside.
This table, linked, shows all the ...
- 80.5k
28
votes
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The Loose Astronaut
This is a great question. I wanted to provide an answer which cited some specific, real-world situations. Currently the only people in space are those aboard the International Space Station. If anyone ...
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28
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Have there been any Spacewalks to free-flying satellites?
with the robotic arm (RMS) first capturing the satellite target
Whilst the CanadArm was involved in capturing the satellites, sometimes the capture was done by people attached to the arm, not by the ...
- 283
27
votes
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Were cosmonauts equipped with poison pills?
I went on a quest to try and get the sources for all the citations for that article; I was partially successful. I have FOIA requests out for the documents I was not able to find on the internet, and ...
- 5,312
26
votes
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How did Apollo 15's depressurization work?
The CSM was always able to be depressurized, since the contingency procedure for getting back from the LM to the CSM, in case the docking mechanism would fail to latch or the doors were unable to open,...
- 14.8k
26
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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.
...
- 189k
24
votes
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Spatial screwdriver
The Pistol Grip Tool has some features not found in DIY or even professional cordless drills.
It can control its torque and speed exactly, and torque/speed/turn count values can be programmed. It ...
- 130k
24
votes
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Why is this astronaut placing a radar reflector?
This was mission STS-61B. The giveaways are the ACCESS payload box and the Mexico logo on the PAM-D sunshield.
The last task of the first EVA was to deploy a small satellite (the radar reflector) to ...
- 189k
24
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Does the speed of ISS slow down at the time of a spacewalk or does it become stationary?
Let's look at Newton's first law:
Law I: Every body persists in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by force ...
- 6,967
21
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Assuming a spacecraft is traveling in a constant rate and our Astronaut will exit it to a space walk, will she be "left behind" by the spacecraft?
I feel this sort of question benefits from a series of thought experiments.
Imagine instead that you've got two astronauts, side by side, zipping through space at some constant speed.
They're kind ...
- 1,867
21
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How was the cosmonaut of the Soviet moon mission supposed to get back in the return vehicle?
There are good diagrams of the Kontakt docking system in the Mir Hardware Heritage document by Portree.
As stated in comments, this was an unpowered, misalignment-tolerant docking system that did not ...
- 189k
20
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The Loose Astronaut
Once the astronaut & space vehicle part ways, they're on two separate orbits. If the force that separated them is impulsive (instantaneous force in a single direction - as in pushing off the ...
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20
votes
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With six spacecraft currently docked at the ISS, how could Santa (or anyone else) deliver presents?
Considering how all the usual docking/berthing ports at the station are occupied, Santa would likely arrive in a Dragon Crew/V2 or a Boeing CST-100 vehicle. These are the next US vehicles that will be ...
- 80.5k
20
votes
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What are the "Big 13" critical contingency spacewalks on the ISS? Have any actually been performed?
The Big 131 are
Pump Module (PM) R&R
Flex Hose Rotary Coupler (FHRC) R&R
Interface Heat Exchanger (IFHX) R&R
Solar Array Wing (SAW) Bearing Motor Roll Ring Module (BMRRM) R&R
SAW ...
- 189k
20
votes
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What (if any) pre-breathes were "attempted" on the ISS, and why?
There is always a prebreathe prior to an EVA from the US side of the ISS.
Prior to each EVA, an oxygen
prebreathe is conducted to prevent
the crew from getting the bends
after depressurization of the
...
- 189k
19
votes
Have there been any Spacewalks to free-flying satellites?
On shuttle mission STS-41C a free-flying crewmember using the Manned Maneuvering Unit flew out to the Solar Max satellite and attempted to dock with it.
(astronaut at lower right)
The docking failed ...
- 189k
18
votes
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Apollo Suit sublimation coolers
Wikipedia says:
As an example, during the Apollo 12 commander's first EVA (of 3 hrs, 44 minutes), 4.75 lb of feedwater were sublimated, and this dissipated 894.4 Btu / hr.
That's 2.154 kg of water ...
- 6,967
18
votes
Did Ed White, on his Gemini 4 spacewalk, have to release pressure from his suit to reenter the capsule?
Not according to the official NASA history, On the Shoulders of Titans.
White had difficulty opening the hatch to start the EVA:
Over the Indian Ocean, White was ready for EVA at last - hoses ...
- 48.4k
18
votes
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What was the "5 minute EVA"? What was the shortest-duration EVA ever?
As far as I've been able to find, the shortest EVA in history was also the first: Alexei Leonov's spacewalk on Voskhod 2 at 12 minutes, 9 seconds.
On the US, side, Ed White's Gemini IV spacewalk ...
- 172k
Only top scored, non community-wiki answers of a minimum length are eligible