That is something I found weird, too. Inflammable and flammable mean the same thing!

Twist: you’re the filtration system.

Your points about a cost-plus contract have merit but aren’t applicable here because the pens weren’t developed under a contract at all. Paul Fisher of the Fisher Pen Company had started developing a pressurized pen before the space program even began (to develop a pen that could write in other orientations than on a desk), although learning of the concerns from the program gave him renewed impetus to solve the design. Fisher patented the design in 1966 after ten years of development and about $1 million in cost. Prior to the pens NASA had been purchasing special pencils at $128.89/each. The original purchase order for the pens bought 400 at $2.95/each.

The Soviet space program bought the pens in 1969, and besides the Americans they’re still used today by the Russian and Chinese space programs. You can buy one yourself for as little as $7 if you don’t care about it being refillable. On the one hand that’s a lot for a disposable pen, on the other hand that’s not terribly expensive for a pen that writes upside-down if you need that, and might not feel too bad if you’re prone to losing pens.

Except this wasn't a cost plus contract, this was NASA buying a thing at discount on the open market. In fact, the USSR paid the same discounted bulk price per pen that NASA did.

To add onto the other comment:
NASA wouldn't have to pay anything if the research didn't work out and maybe even avoided other companies who then weren't compensated for their efforts.

Also your body doesn't do a good job of breaking it down either. Id imagine that in your lungs would suck.

I have a piece of graphite in my leg from 7th grade still. I'm 33.

In technical safety terms, combustibles are harder to ignite than flammables. So diesel and olive oil are combustibles, for example, because neither of them give off enough ignitable vapour at room temperature. Ethanol does, so it gets classified as flammable, and you need to store and handle it more carefully than diesel. Then there's really horrible stuff like triethylborane which will catch fire upon meeting oxygen even at temperatures well below the freezing point of water

Of course in casual usage they mean the same thing

They’re referring to the relationship between surface area and combustion. Talc, for example, melts but does not burn. Talc powder can ignite if blown over an open flame.

You're not dense for asking a question. Without asking questions, it's Impossible to learn.

The flash point is different. The flash point is the temperature that is necessary to create enough vapor for the substance to ignite.

Flammable material has a low flash point, which means it catches on fire easily. Think gasoline. Combustibles need a higher initial temperature, but eventually they will burn and sustain the burning until running out. Think wood.

at least those three were known, acknowledged and not covered in secrecy.

we really have no idea how many the sov's lost in their rush to stay ahead / catch up to the moon landings. truly, there's no way to fucking know, even the cosmonauts themselves never knew the total extent.

maybe they both deserve to be dragged a bit eh? pfft