I read on Speedmaster Professional made by Omega remains to this day the only watch admitted by NASA for EVA use. This is a mechanical watch (though a manual winding one, not an automatic watch). Why would you want to use this rather than any of the easily available alternatives nowadays? I would imagine that a quartz watch with a digital display, having no moving parts, would be superior to a watch with a mechanical movement in terms of reliability, robustness, and accuracy in timekeeping (it should also be superior in terms of cost, though that’s probably not much of a concern for a space program). Are there any rational (i.e., other than e.g. nostalgia and traditions) reasons that could explain why a mechanical watch is the timekeeping instrument of choice for astronauts?
No idea. Maybe the batteries are an explosion danger somehow?
I believe the answers you seek are in the same article you linked to.
If the watch is worn outside the space suit (which, I would think it would have to be, to see it), then the extreme temperature range might make a quartz watch inaccurate, or fail completely.
The batteries won’t work at low temperature, and might leak at high temperatures.
Also, the crystal will be operating well outside it’s calibration range.
A standard LCD doesn’t have a large temperature range that it would be visible. And (pure speculation here) I wonder if any of the liquid would outgas in a vacuum?
That would be my guess for commercial LCD panels, though there space-qualified liquid crystal devices.
I suspect the battery is a bigger concern. Commercial watch batteries may outgas or rupture when exposed to vacuum. And worse, if a battery does rupture, the chemicals that leak out may do damage to other things. Mechanical watches don’t contain any liquids or volatile chemicals.
I think if someone were to design a “space watch” from scratch, it would be an electronic quartz watch powered by vacuum-compatible batteries, using sealed LCD panels or LED. And it will likely be more bulky than an Omega, and cost a whole lot more (including development cost).
I would expect the opposite: That it would be smaller and cheaper. The devil is in getting to that point: It’s fairly easy to make something that will work properly in space, but difficult and expensive to verify that it’ll work properly in space. So once you’ve done that for one product, there’s an incentive to keep using that product, so you don’t have to go through the verification process again.
It was, apparently. See the pics on this Rolex forum thread — Ed White’s Gemini 4 EVA, and someone on the moon with one (hard to tell who):
From that article:
It did make me laugh to read that one of the companies that submitted a watch for testing sent in a pocket watch. Now I have an image in my head of a spacesuit with a watch pocket.
The article says that quartz watches hadn’t been developed when the initial tests were done in 1965. That’s not an explanation as to why they’re not being used now.
My best guess is that with recent(and future) budget cuts retesting wrist watches is on the bottom of the list…if it is on the list at all.
They’re not used now because they don’t need to be, because they already have something that is known to work well.
Even if the astronauts were required to buy their own fancy mechanical watches, upon return to the Earth each watch is going to be worth Much more than the purchase price.
And they don’t have to buy them, because the watch company probably gives them to NASA, because there’s a lot of marketing value in being able to say “this is the watch that astronauts wear”.
I’m pretty sure government agencies aren’t allowed to do that.
Also, do astronauts really need wristwatches during EVA? Astronauts should be in constant contact with the station/spacecraft as well as ground control. They can just ask what time it is. And they probably don’t even need to ask - someone would tell them if they were falling behind schedule, etc.
p.s. The current design NASA EVA suit has a digital display & control system. If knowing the current time was critical, I think the “current time” display would be incorporated into this unit, rather than being a separate thing you wear. (And maybe it is, I’m not sure.)
Fisher’s gotten 50 years of publicity out of being the provider of pens for NASA astronauts.
Andy Weir, author of The Martian seems to think so.
Each crewman had their own laptop. So I have six at my disposal.
Rather, I “had” six. I now have five. I thought a laptop would be fine
outside. It’s just electronics, right? It’ll keep warm enough to operate in
the short term, and it doesn’t need air for anything.
It died instantly. The screen went black before I was out of the
airlock. Turns out the “L” in “LCD” stands for “Liquid.” I guess it either
froze or boiled off. Maybe I’ll post a consumer review. “Brought product
to surface of Mars. It stopped working. 0/10.”
The temperature range of LCDs is quite restrictive.
Their viewing angle changes with temperature, and even though they may not be damaged by low or high temperatures, they become unreadable.
I would think that boiling would be much less of an issue with the liquid crystal itself compared with freezing.
Here is a PDF of some tests.
Also, LCDs are not even necessary - there are plenty of quartz watches with mechanical movements.
But the information in kenobi’s link shows that the current Display Control Module uses a 12-character alphanumeric LCD.