And, as you guys have figured out, I'm a space nerd. And a watch nerd. Let's see what happens when these two worlds collide...
I did a bit of digging, to see what watches are currently approved by NASA. Note ONLY the mechanical Speedmaster Professional is approved for EVA. I am unable to nail down if all the available movements are approved, or only the original 321 movement... That's not clear to me.
But, if you like watches, and space, you may enjoy this post.
1) Omega Speedmaster Professional (mechanical, hand-wind). The caliber 321 movement is the "true" moonwatch. They command a premium on the secondary market. I had a list of serial numbers at one time but it's lost. I think the newest one was from 1967. (photo is a 1968 model). These were "upgraded" with the JB Champion bracelet (also expensive on the secondary market) and also issued with the Velcro strap. Years ago I was able to purchase one of these straps (they DO NOT have a part number on them, like all the reproductions on eBay do). It is crazy long, to be worn over the old EVA suit, and has to be wrapped twice around the bare wrist to be worn that way. (One of the astronauts is shown wearing it this way)
Omega Speedmaster Professional X-33
Gen 1 (seen on Doug Hurley)
Gen 2 [eBay] (Seen on Bob Behnken's wrist) Note the crown change (because it is used push-pull, not turning), and bezel change with added glowing pip. Bezel also rotates bi-directionally, as opposed to the gen 1 which only rotates counter-clockwise. It also has a uniform color, whereas the gen 1 has a bit of "bling" with the polished bezel insert and pushers.
(Aug. 19, 2021) --- Expedition 65 Commander Akihiko Hoshide wearing a Gen 2
(Aug. 16, 2021) --- Expedition 65 Flight Engineers Shane Kimbrough (gen 2) and Megan McArthur (Baby G)
I have heard that although these are officially discontinued (and replaced by below), they are still available to military and NASA as special order. I am currently trying to get a gen 1 strap for mine, to go along with the bracelet, and I'll report back what I hear. The Gen 1 is not seen much any longer, and I presume only the Gen 2 would be available for new purchase.
Gen 3 "Skywalker" X-33 (Standard variant/color shown) This watch is approved by NASA, ROSCOSMOS and ESA for non-EVA use
(no digital/quartz watch is approved for EVA). There is also a green trimmed one "Solar Impulse", and a blue trimmed one, which was a variant used as a yachting timer (most likely not approved) Bear in mind this is a big watch as well- 44mm I believe. (gen 1 & 2 are 42mm)
During the shuttle era, several digital watches were approved:
Casio DW-5600 (C and E suffix)
"C" suffix (~1990) [Photo from eBay]
"E" Suffix [also from eBay]
Casio DW-5900 (no suffix specified)
DW-5900 (no suffix) from 1992 [eBay again]
Casio G-9000 "mudman"
I don't know if there is a specific color or variant of this one, but if you like big watches, this is a good choice. There are some other variants (black and orange for example) that are much less common. Note the "white" one is actually light gray above.
Timex Ironman Datalink (model 78701)
This is a hard to find one these days. It has a USB cable (and 3-1/4" floppy disc!) and can store phone numbers etc. Note there are several color variants, as well as slight case changes over it's lifetime, but this one pictured I
believe to be the particular model approved/flown by NASA. I don't think ANYONE at NASA still wears one however.
I think, at this point, watches are up to the astronauts to some extent. I see a few others I have not positively identified on other astronauts- particularly the women (note Meghan's Baby G, above, on the ISS). But, the photos are not off-planet, and here, you can wear whatever you like, so that does not mean a whole lot...