Spyderco Forums

yes, it was a Victorinox OHO Hunter Pro with orange handle :rolleyes:
yes, LC200N was developed for bearings in NASA Space systems
yes this thread rocks, :D
yes, there should be two knives for space: :cool:
one used for astronauts on board stations and ships, without suits or gloves
another different one used for space suit use, walks and repairs on the outside, harsh atmospheres and low dexterity

Whatever else the imagined Spydie might have, I hope it’s a sheepsfoot. Poking a hole in a spacesuit is already a hazard and shouldn’t be made worse.

wrdwrght wrote: ↑

Thu Jun 28, 2018 12:37 pm

Whatever else the imagined Spydie might have, I hope it’s a sheepsfoot. Poking a hole in a spacesuit is already a hazard and shouldn’t be made worse.

A spacesuit is extremely resistant to tears and cuts. You won't poke a hole in it with your knife lol. There are even stab-proof shirts for kids these days, now imagine a multi-million dollar space suit. I'm more inclined for a normal, drop point style blade with a bit of belly. As far as I remember, all knives sent in space had a similar design. Its most important function is cutting insulation, plastic, rubber, slicing tasks here and there. So it needs to be multifunctional. A sheepsfoot is too specialized.

emanuel wrote: ↑

Thu Jun 28, 2018 12:31 pm

You are confusing Cobalt 59, the natural, by far the most abundant and only stable cobalt isotope, with Cobalt 60, a synthetic radioactive isotope that has the property you mentioned. The cobalt extracted from ore used in knives is safe to use in high radiation environments.

Cobalt-59 is indeed the common stable isotope found in nature. However, when it captures a neutron, it becomes Cobalt-60, which is highly radioactive. Cobalt-59 readily absorbs neutrons and becomes Cobalt-60. Cobalt-59 is very much *not* safe to use in high radiation environments for this reason.

sal wrote: ↑

Thu Jun 28, 2018 10:23 am

What chores and functions might this space knife have to perform?

sal

It should sit there and look pretty.

Accutron wrote: ↑

Thu Jun 28, 2018 12:56 pm

emanuel wrote: ↑

Thu Jun 28, 2018 12:31 pm

You are confusing Cobalt 59, the natural, by far the most abundant and only stable cobalt isotope, with Cobalt 60, a synthetic radioactive isotope that has the property you mentioned. The cobalt extracted from ore used in knives is safe to use in high radiation environments.

Cobalt-59 is indeed the common stable isotope found in nature. However, when it captures a neutron, it becomes Cobalt-60, which is highly radioactive. Cobalt-59 readily absorbs neutrons and becomes Cobalt-60. Cobalt-59 is very much *not* safe to use in high radiation environments for this reason.

The chances of that happening in large enough amounts are close to zero. Cobalt, like all elements, is not a neutron magnet, it has to be hit just right AND with enough force. This last part is important, that's why cobalt 60 doesn't form in nature, you need laboratory conditions for neutrons to have such high energies. You could say the same for a magnitude of elements that that could happen and pose the same risk. Molybdenum is one of them. Chromium too. If you are working in an environment with such high neutron density that your knife starts glowing, you're already dead or riddled with cancer by a long time already.

Opening packs of astronaut ice cream?

Accutron wrote: ↑

Thu Jun 28, 2018 12:56 pm

emanuel wrote: ↑

Thu Jun 28, 2018 12:31 pm

You are confusing Cobalt 59, the natural, by far the most abundant and only stable cobalt isotope, with Cobalt 60, a synthetic radioactive isotope that has the property you mentioned. The cobalt extracted from ore used in knives is safe to use in high radiation environments.

Cobalt-59 is indeed the common stable isotope found in nature. However, when it captures a neutron, it becomes Cobalt-60, which is highly radioactive. Cobalt-59 readily absorbs neutrons and becomes Cobalt-60. Cobalt-59 is very much *not* safe to use in high radiation environments for this reason.

Oy, we are not talking about “high” radiation areas here (that term actually means something in rad safety). There are also no free neutrons in space, they have a half-life of 15 min. Neutrons are only present from nuclear fragmentation/spallation reactions with the spacecraft hull/contents. These neutron energies are not typically high enough to be captured by high neutron cross-section materials anyway... Radiation safety is a great concern up there, it’s exactly what I work on, neutrons are not high up there on the list of concerns compared to solar protons and galactic cosmic radiation (high energy light and heavy charged particles). What’s also vastly more concerning is that the astronaut will lose function well before their knife does.

After a 7 year dry spell of funding, NASA was given 20 billion in funding in March of 2017. Space exploration is our future, glad it's getting the attention it deserves.

I'd say a space knife should have high edge retention, you don't really want to sharpen in space where all the metal 'dust' can float around right?

SE or combo edge.

emanuel wrote: ↑

Thu Jun 28, 2018 1:04 pm

The chances of that happening in large enough amounts are close to zero. Cobalt, like all elements, is not a neutron magnet, it has to be hit just right AND with enough force. This last part is important, that's why cobalt 60 doesn't form in nature, you need laboratory conditions for neutrons to have such high energies. You could say the same for a magnitude of elements that that could happen and pose the same risk. Molybdenum is one of them. Chromium too. If you are working in an environment with such high neutron density that your knife starts glowing, you're already dead or riddled with cancer by a long time already.

Co-59 has a neutron cross section thousands of times higher than most other elements, and it's a neutron absorber, not a scatterer. It *easily* transforms into Co-60. Only a handful of lanthanides and heavy transition metals have a higher neutron cross section, none of which are used in any conventional alloys. The neutron cross section of Co-59 is about 20x larger than U-235, almost 2000x larger than Fe-56, almost 4000x larger than Mo-96, and about 2200x larger than Cr-52. Co-59 is very specifically excluded from use in environments where neutron capture is a possibility.

I would generally think that the temperature extremes would pose the greatest threat to a conventional earth knife.

Orbital temps (on a satellite, for instance) can range from -100 C to +150 C, which is -148 F to 302 F.

Obviously, a future astronaut won't be hanging on to anything at those temperature extremes, but if they left it exposed to those temps, it'd be nice to come back to a knife where the handle isn't falling off or the knife temper isn't lost.

Also, conventional steel experiences a ductile-to-brittle transition when chilled. It might be better to have an austenitic steel in place.

Accutron wrote: ↑

Thu Jun 28, 2018 1:26 pm

Co-59 has a neutron cross section thousands of times higher than most other elements, and it's a neutron absorber, not a scatterer. It *easily* transforms into Co-60. Only a handful of lanthanides and heavy transition metals have a higher neutron cross section, none of which are used in any conventional alloys. The neutron cross section of Co-59 is about 20x larger than U-235, almost 2000x larger than Fe-56, almost 4000x larger than Mo-96, and about 2200x larger than Cr-52. Co-59 is very specifically excluded from use in environments where neutron capture is a possibility.

Thanks for the info, I didn't knew that. Well, either way, as RadioactiveSpyder also explained, thank god outer space doesn't have high energy neutrons that would allow such things to happen in a significant amount. So places where its safe for the astronaut, would be safe for his cobalt rich knife :P

RadioactiveSpyder wrote: ↑

Thu Jun 28, 2018 1:08 pm

Oy, we are not talking about “high” radiation areas here (that term actually means something in rad safety). There are also no free neutrons in space, they have a half-life of 15 min. Neutrons are only present from nuclear fragmentation/spallation reactions with the spacecraft hull/contents. These neutron energies are not typically high enough to be captured by high neutron cross-section materials anyway... Radiation safety is a great concern up there, it’s exactly what I work on, neutrons are not high up there on the list of concerns compared to solar protons and galactic cosmic radiation (high energy light and heavy charged particles). What’s also vastly more concerning is that the astronaut will lose function well before their knife does.

MeV-range solar neutron flux can be observed in orbit. Neutron leakage flux is also generated by cosmic rays interacting with the upper atmosphere. It is certainly not an environment devoid of high energy free neutrons.

Cutting up Martian sushi?

sal

OK folks, Google and NASA’s abundant number of websites on the topic of space radiation are easily found and very interesting reads. Here’s a good one that summarizes the problem:

https://www.nasa.gov/feature/goddard/re ... on-on-mars

I’ll repeat again that neutron exposures to astronauts occurs primarily through proton and other light/heavy ions fragmenting portions of the spacecraft and its contents, including the astronauts themselves. Health effects of exposure to protons and other charged particles is the only thing our NASA program studies, neutron exposures are not generally considered except as additive to the effects we see with protons and heavier charged particles, especially since neutrons don’t do a darn thing until they hit an atomic nucleus and generate - you guessed it! - more protons and charged particles that are actually responsible for dose delivery (same way that gamma rays don’t do anything until the actually eject an orbital electron, the photoelectron is what causes the damage). It’s a fascinating area of research actually...

If we are to think of a knife, I think it should be very light in weight, have a pocket clip, and have a larger thumb hole than currently in use so that even gloved hands have a chance at operating it. A 3" to 3.5" blade with a sharp tip, but one not easily broken. The blade should not be overly wide as spaces are tight. As to materials, perhaps Ti for handles. I say this because I am not sure how G10 or FRN would stand up to radiation. If we knew that they could withstand the constant bombardment of radiation, then that would change matters. A knife that is a multi-tool would be extremely handy, I would think. Something on the order of the current Vic Soldier's Knife is what I have in mind, but with better materials. It needs to have traction inserts or that wonderful bi-directional texturing Spyderco is so good at.

Here is what I consider to be near optimal:



However, I think the Phillips head and the awl need to be able to be removed and placed on the end where the flathead is, and vice verse.

Ask Sigourney Weaver.

I spent a few years working on Extravehicular Activity (EVA) hardware (spacewalk stuff) at Johnson Space Center, including the period after the Columbia accident. We didn't fly shuttles for a few years after that, and all our US spacesuits on orbit were taken offline due to the lack of maintenance parts. To continue working outside we had to rely on the much simpler (and less capable) Russian suits, and I ended up on one of the teams figuring out how to adapt our tools and equipment to the Russian suit.

One thing that always gave our US safety board fits was the Russian "EVA Knife" - a large blade with a cylindrical cover that was part of the standard Russian safety kit. The idea was that if a Cosmonaut was tangled in the restraint tethers, they could cut their way out (our US ERCM crew tethers use a steel cable). The Russians insisted it was an important safety item, but the hyper risk averse US safety board couldn't wrap their brain around an exposed blade on EVA...

The safety panel had always been so concerned with sharp edges on EVA that everyone processing tools and equipment on the ground carried a small piece of spacesuit glove material (glove swatches we called them), and rubbed it over every suspect corner or edge of every tool prior to launch. If the fabric backed silicone was cut, the hardware required rework.

The more conventional guns and knives usually associated with the Russian space program were actually part of the survival kit in the capsules, as the Russians land in pretty wild country (especially early on in their space program) and it was assumed they might need "tools" until the recovery team arrived.

-rwponline

Oh, and I should mention that I opened lots and lots of 'pink poly' heat sealed bags (filled with EVA tools and equipment) with a Spyderco while working there. Everything had to be double bagged in the clean room before being checked back into controlled storage for the next mission.

Bloke wrote: ↑

Thu Jun 28, 2018 5:44 pm