Questions tagged [safety]
Questions regarding space exploration safety issues and procedures.
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What makes (or at least made) Ada the language of choice for the ISS's safety-critical systems?
We have it on good authority that Ada is widely used for "safety critical software" on at least the US side of the International Space Station.
Of all the possible languages to choose from, ...
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What safety protocols did this Pythom Space rocket crew ignore?
The video below of Pythom Space's first rocket test has raised a few eyebrows
The video prompted hundreds of replies on Twitter, including some from rather horrified rocket scientists. "We knew ...
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What is the primary reason for SpaceX motion to have astronauts board Dragon before fueling up the rocket?
News piece: NASA supports SpaceX plan to fuel rockets with astronauts on board.
The move is criticized by many as unnecessarily dangerous.
From what I understand though, it shouldn't be necessary - ...
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Why would a box full of 1cm balls released into LEO be so scary to an engineer supporting the ISS?
update March 2018: I just saw this in Buzzfeed (Google sent me there, I don't normally read it): Rich People Will Soon Be Able To Buy Fake Meteor Showers On Demand. It seems this might happen in 2018.
...
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Are there any safe-to-launch alternatives to RTG's for outer solar system exploration?
In the past two decades, NASA has launched at least three missions that use RTG's:
Cassini
Mars Science Laboratory
New Horizons
Those launches include plutonium, which is a reason for some to oppose ...
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How did sloshing prevent the Apollo Service Module from moving safely away from the Command Module and how was this fixed?
The Insider.com article 'We could have lost the Apollo 11 crew:' A once-classified anomaly nearly killed NASA's first moon astronauts, a new book reveals describes a problem during reentry of several ...
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August 30th 2018 Soyuz leak, any dangers for re-entry?
On August 30th 2018, Soyuz MS-09 had a leak that was fixed by the ISS crew (source).
Does the leak/fix have any consequences on using the Soyuz for returning to Earth?
Would the fix hold the stress ...
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How are cryogenic rocket propellants delivered to the launch pad?
I work at a university that gets LN2/LHe (liquid nitrogen and helium) delivered a couple times a week by a large tanker truck outside my office. It seems to work well enough to deliver a couple tons ...
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What were the Top 10 Shuttle Risks in John Young's "famous letter"?
Whilst reading A Technical History of the External Tank I ran across this comment:
Although the problem has not recurred, John Young, in his
famous top ten Shuttle risk letter ...
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How intrusive was the Apollo Master Alarm system?
During the Apollo 11 landing, a misconfiguration caused the guidance computer to activate the 1201 and 1202 program alarms, signifying that the computer was overloaded and dropping low-priority tasks. ...
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Why is it assumed that space flights have to be safe?
On the one hand, space travel is a completely novel technology and less than 1000 people have traveled outside the planet. On the other hand, every accident in space involving humans is treated as a ...
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How dangerous are RCS thrusters?
How dangerous are RCS thrusters, in a vacuum, to A. other spacecraft, especially when docking, and B. astronauts in EVA suits? How far away do you have to be to be safe / do RCS thrusters need to be ...
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Is it safe to observe the ISS with the naked eye?
As far as I understand, when we view the ISS, it is because the sunrays get reflected from the solar panels of the ISS and reach us at the appropriate angle. So that would be equivalent to viewing the ...
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Why is dust such a problem in microgravity? Wouldn't proper air circulation and filtration take care of it?
Dust and small particles in microgravity environments are generally regarded as bad, and items prone to generating these tend to be discouraged:
Bread should be prepared quite differently, so that it ...
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What is the procedure if communication with the ISS is lost for an extended period?
Between ground control and the ISS there is the occasional short communications loss which they are obviously able to deal with, but is there a procedure to follow if the communication is lost for ...
user106
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Any possible setbacks in deorbiting larger space junk and let it burn up upon reentry into atmosphere?
Space junk, orbital debris, or space waste pose a risk on functional satellites and space laboratories / stations in orbit around Earth. According to Wikipedia:
Currently about 19,000 pieces of ...
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Is the overall mortality rate for being in a spacecraft in space or bound for space about 4%?
I just read this answer in astronomy.stackexchange, where a sobering point was made that the overall to-date chance of losing ones life in a spacecraft is about 4%.
While I don't want to dwell on ...
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What is the "ISS's Keep Out Sphere" and what is its radius?
The comment:
In a similar vein, it would be interesting to know if going around the moon rather than to the ISS removes any legal hurdles. Do we have any questions covering the legal ramifications (...
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What was the space-worthiness determination procedure for STS-1?
I am specifically interested in on-ground tests that were conducted after the full shuttle was pieced together (orbiter, tank, engine, boosters) for the first time (before STS-1).
Of course the ...
user40
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Wouldn't it make sense to use parachutes for aborting test flights rather than destroying the whole rocket?
Recently, a SpaceX test flight was aborted by blasting the whole device.
Wouldn't it make sense to have parts of such rocket be equipped with parachutes when test flights are performed, so at least ...
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Is the EU really banning "toxic propellants" in 2020? How is that going to work?
This comment links to an archived presentation by Tesseract "The space transportation company offering revolutionary propulsion" says on slide 8:
Timing is right
Small satellite ...
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What does it mean for a launcher to be 'nuclear-certified'?
This article says NASA has booked a nuclear-certified Atlas 5 for the launch of the Mars 2020 rover, and says this:
currently, Atlas 5 is the only launch vehicle that holds a NASA
certification ...
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Does the SpaceX spacesuit address any of the criticisms of ACES raised by Columbia Crew Survival Investigation Report?
A brief history of what Shuttle crews wore for ascent and entry, from the Columbia Crew Survival Investigation Report:
The shuttle was originally designed to be operated in a shirtsleeve (bare-hands) ...
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Historically, how risky are first launches of new rockets?
Apropos of the Falcon Heavy test flight scheduled for February 6, 2018, what is the failure rate of first launches of new orbital rocket designs?
How has this rate changed over time since the 1950s?
...
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How does the launch risk posed by plutonium compare to the launch risk posed by propellants?
For outer solar system exploration, virtually the only feasible power subsystem are Radioisotope thermoelectric generators (RTGs). These include plutonium, which may carry considerable risks (see ...
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What types of items are prohibited on space missions?
What items are not allowed to be brought aboard space exploration missions?
What can't be brought back from a space mission (without prior authorization)?
Why were these regulations originally put ...
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How long were the Apollo astronauts allowed to breathe 100% oxygen at 1 atmosphere continuously?
This answer explains that from the time they suited up "in the Suit Lab before launch" until the time the capsule started depressurizing during ascent, the Apollo astronauts were breathing 100% oxygen ...
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How does the launch risk for a plutonium RTG and a uranium fission reactor compare?
I was looking at this answer that talks about how a good alternative to Radioisotope Thermoelectric Generators would be fission reactors. It makes a number of good points, but in the comment thread ...
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Tiny emergency propulsive device if stuck floating in a large volume in microgravity
The questions here in SXSE Can you swim in space? and in Physics SE How to escape the center of a room without gravity? [closed] both address aspects of how to move if stuck floating in the center of ...
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Has any spacecraft had a way for the crew to escape during reentry?
All manned spacecraft to date have come back to Earth eventually, and when they do it's through a flaming ball of plasma.
It seems too probable that this plasma would have a way of breaking things ...
user12
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Why does Blue Origin claim Virgin Galactic's spaceplane doesn’t have an escape system whereas Virgin Galactic's passengers are wearing parachutes?
https://twitter.com/blueorigin/status/1413521631717122059 (mirror):
vs. https://space.stackexchange.com/a/54072/1111 by John Thomas:
[Virgin Galactic's passengers] do appear to be wearing parachutes....
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Did the U.S. Space Shuttles have a way for crew to bail out?
This recent question regarding the Space Shuttle Columbia disaster mentions the possibility that the crew could have bailed out if the orbiter could have successfully descended to 25,000 feet before ...
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How is the periscope port on Soyuz spacecraft secured for the atmospheric reentry?
Soyuz Backup Periscope (ВСК-4) is used in Soyuz spacecraft to align itself for orbital corrections, deorbit burn, and rendezvous with the International Space Station. Here is a cute closeup photograph ...
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Do all dangerous asteroids first pass through keyholes?
Scitech Daily's MIT Engineers Devise the Best Way to Deflect an Incoming Planet-Killer Asteroid
Now MIT researchers have devised a framework for deciding which type of mission would be most ...
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Engineering difficulties towards near-perfect rockets?
So in the light of some technical failures last year, I recently had a discussion about engineering endeavours throughout human history. An interesting recent adventure is the revival of rocketry. ...
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How are SRBs and solid rocket motors transported safely? Do they ever end up on trucks driven down public highways?
The BBC News article The Rocket Scientists Mixing Up a Giant Firework begins with:
In a remote corner of tropical South American jungle, French scientists are mixing a ‘cake’ with a difference – a ...
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Was this a rapid SCHEDULED disassembly? How was it done?
The new Curious Droid video Apollo's Forgotten Computer - The LVDC discussed the Saturn V flight computer that's also discussed in answers to Is this really the Saturn V computer only, or are there ...
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What is the ortho/para issue with LH2 as a fuel?
I remember reading somewhere that a catalyst was used to change the ratio of ortho- vs para-hydrogen before it is loaded as LH2 propellant on a rocket.
What is this exactly, and why is it necessary? ...
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How are differences in electrical potential between docking (or berthing) vehicles mitigated?
Different vehicles can have several hundred or even several thousand volts difference between their baseline electrical potentials. How do they ensure that upon first contact, there isn't a massive ...
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For a launch, how is safe viewing distance determined?
In determining safe viewing distance, seems to me there are discrete threats to consider:
First is the rocket blowing up on the pad, or just above it. That would have no warning. There would be a ...
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Does Crew Dragon have a quick-release hatch?
After today's Crew Dragon launch was scrubbed, it took the pad ninjas at least ten minutes to open the hatch. One of the major criticisms of the Apollo Block 1 hatch design after the Apollo 1 fire ...
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Earthing system in space?
On Earth, we have a good reason to deploy electric devices with an "Earthing system": this helps to avoid dangerous leak currents on surfaces.
Now how is this solved on a spacecraft?
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Did the Apollo missions fly "over the top" of the Van Allen radiation belts?
In the video The Moon Trees That Flew To The Moon On Apollo 14 after about 08:47 Scott Manley says that Apollo 14 "flew up over the top" of the Van Allen radiation ...
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SpaceX CRS-7 failure because of a bad strut — is it a sign of bad structural design?
In June 2015, SpaceX's mission CRS-7 on Falcon 9 was lost when the rocket exploded on takeoff. SpaceX investigation concluded that the problem was a failure of a single defective strut. The strut's ...
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Will a computer be allowed to "self-destruct" astronauts (or passengers)?
In the video clip of this interview, captioned:
General Wayne Monteith, 45th Space Wing Commander, talks about the Autonomous Flight Safety System, or AFSS -- a new, automated way of having a ...
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Where does space travel rank in per-passenger-mile safety?
Air travel is the safest method of transportation, with 0.07 deaths every billion passenger-miles. While space travel certainly has a higher fatality rate per-space-traveller (~3%)1, 2, where does it ...
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What is the procedure in case the ISS loses one of the evacuation crafts?
Suppose that a micrometeorite or a sudden failure renders one of the Soyuz inoperable, or that a routine inspection discovers a defect in one of them that makes it unsafe.
What is the protocol to ...
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What psychological therapy is available to space travelers
Is there an 'on-call' person dedicated for psychological therapy of people traveling in space? Flights are getting longer and longer, and while isolation has been studied for space and certainly ...
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How radioactive is surface regolith on the Moon?
Use of regolith for shielding from cosmic radiation seems the most practical solution for perspective lunar surface bases.
But lunar regolith should gather some secondary radiation while being ...
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Most unsafe foods in zero gravity [closed]
Mostly this question (and some earlier knowledge about food & drink behaviour in space) made me think that which are those foods that would mean a serious threat for people in space?
My two ...
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