Temperature on the surface of the moon!

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The guy probably told Aldrin that he didn't believe the U S landed on the moon. And who would sentence Aldrin to a jail sentence for assault?
 
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Yep, that's exactly right. Apparently he had been stalking him for days from event to event accusing him of being a liar...blah...blah...and then finally Aldrin snapped at being called a coward. Here is the slightly longer version which provides a context.

 
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That's a 500° F variation every 13 hours! 😕 I look at my Speedmaster and my Speedmaster Professional (both 1989 versions), and wonder how it might have been possible for such a watch to survive under those conditions! Anyone know?

And what on earth (or rather, what on moon 😁) would you do if you were on the dark side, and your visor fogged!

I think you mean the far side of the moon. The dark side of the moon was an album by Pink Floyd. And a rather good one 👍

Also, the 500 degree variation would be every 14 days since the moon spins once on its axis every 28 days. 😉
 
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Of course! 14 DAYS! What was I thinking? Or perhaps was I even thinking?
 
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Happy new year all.
 
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I am not 100% sure of the temperatures experienced by the speedy whilst on the moon but I will apply some heat transfer to analyze the situation.

Assumptions: ( all reasonable )
The speedmaster is strapped on the wrist of the astronaut. If the astronaut was in his space shuttle ( or what ever its called that he took the trip in from the earth to the moon) for a long time ( like they where) the temperature of the watch is somewhere between the temperature of the space shuttle and body temperature ( assuming they wore it the whole time and didn't have it laying around and strapped it on for walks only, if this was the case it would be the same temperature as the space shuttle).

Analysis:
if the astronaut went for a space walk and exposed the watch ( not underneath the suit but on top of it as was) the temperature would start to change. The important thing is to remember that the change of temperature change is not instantaneous, it would take time for it to cool down(or heat up) ( like a turkey in the oven, it does not instantaneously change to the temperature of your oven). if the space walk was not ridiculously long it would not reach a steady state ( temperature not change over time) so it would not have hit the maximum or minimum temperature that could be experienced ( the temperature extremes of the moon), it would be between the starting temp ( the temperature of watch as it left the space suttee) and the extreme temperatures on the moon.

The stainless steel part of the watch would transfer energy by radiation slowly if it was polished stainless steel, as it probably was since they got brand new watches. this is due to the emissivity of polished stainless steel as seen below ( a value closer to 1 means more effective radiative heat transfer, 0 would imply none)

Stainless Steel weathered emissivity =0.85
Stainless Steel polished emissvity= 0.075 ( note how close it is to 0 on the scale of 0 to 1)

The watch crystal would transfer heat by radiation significantly due to its emissivity. I could not find values for hesalite but here it is for plastic:

Plastics emissivity = 0.91 ( hesalite should be around here, glass is also around this value)

Luckily the movement of the watch would change temperature slower in comparison the outer surface of the crystal since the trapped air between the dial and the crystal acts as a layer of insulation ( a pretty good one ).

The watch would be heated ( or cooled) by the astronaut by conduction from his body ( more accurately from his suit, that would be heated by conduction through the air in his suit ( conduction and not convection due to such a small space between the suit and the body ( the air is heated by his body)). The watch at the same time is being cooled ( or heated) by radiation. There is also a small ( negligible really, but none the less it still exists) amount of heat being generated by the friction of the moving parts in the watch). Due to this, even if the space walks where really long the maximum or minimum temperatures experienced would not be exactly that of the extreme temperatures on the moon.

I looked up the durations of space walks on the moon, a lot where really short ( 12 - 40 mins ) and i believe due to the reasons i mentioned above the movement would not have had time to reach any ridiculous temperature, allowing it work properly. some of the longer ones ( 2 hrs+ ( there where not many)) it could have come close, but I'm not certain as actually solving the math behind the equations that model this situation would take a while ( and i definitively lack 1 or two pieces of info i would need to solve it).


TLDR: the movement probably never saw the extreme temperatures mentioned above seen on the moon).
 
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An interesting comment made earlier in the thread was that two Speedmaster Professionals that were worn on the moon (11 total), failed. That could have been from an impact on the LEM or the Rover, a moon rock, or some other form of equipment. Or they could have failed, being expected to function in temperatures tha varied by 500° F, from hot to cold. So, surviving as they did, as well as they did, under such conditions, truly is remarkable in my view. I wonder if they had the presence of mind to land somewhere near the demarcation line between the sunny side and the dark side where, (for a day or so at least) the temperature might have been more, ahem, temperate!
 
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Thought we only ever see the one side of the moon, so there would not be a variation every 12-13 hours as the moon is always one side light and the other dark it just disappear,s as the earth turns....

But don't ask me anything about space or the moon as only have the watch, In case it is needed one day.... Other than that I'm out of this technical jumbo mumbo...
 
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I am not 100% sure of the temperatures experienced by the speedy whilst on the moon but I will apply some heat transfer to analyze the situation.

Assumptions: ( all reasonable )
The speedmaster is strapped on the wrist of the astronaut. If the astronaut was in his space shuttle ( or what ever its called that he took the trip in from the earth to the moon) for a long time ( like they where) the temperature of the watch is somewhere between the temperature of the space shuttle and body temperature ( assuming they wore it the whole time and didn't have it laying around and strapped it on for walks only, if this was the case it would be the same temperature as the space shuttle).

Analysis:
if the astronaut went for a space walk and exposed the watch ( not underneath the suit but on top of it as was) the temperature would start to change. The important thing is to remember that the change of temperature change is not instantaneous, it would take time for it to cool down(or heat up) ( like a turkey in the oven, it does not instantaneously change to the temperature of your oven). if the space walk was not ridiculously long it would not reach a steady state ( temperature not change over time) so it would not have hit the maximum or minimum temperature that could be experienced ( the temperature extremes of the moon), it would be between the starting temp ( the temperature of watch as it left the space suttee) and the extreme temperatures on the moon.

The stainless steel part of the watch would transfer energy by radiation slowly if it was polished stainless steel, as it probably was since they got brand new watches. this is due to the emissivity of polished stainless steel as seen below ( a value closer to 1 means more effective radiative heat transfer, 0 would imply none)

Stainless Steel weathered emissivity =0.85
Stainless Steel polished emissvity= 0.075 ( note how close it is to 0 on the scale of 0 to 1)

The watch crystal would transfer heat by radiation significantly due to its emissivity. I could not find values for hesalite but here it is for plastic:

Plastics emissivity = 0.91 ( hesalite should be around here, glass is also around this value)

Luckily the movement of the watch would change temperature slower in comparison the outer surface of the crystal since the trapped air between the dial and the crystal acts as a layer of insulation ( a pretty good one ).

The watch would be heated ( or cooled) by the astronaut by conduction from his body ( more accurately from his suit, that would be heated by conduction through the air in his suit ( conduction and not convection due to such a small space between the suit and the body ( the air is heated by his body)). The watch at the same time is being cooled ( or heated) by radiation. There is also a small ( negligible really, but none the less it still exists) amount of heat being generated by the friction of the moving parts in the watch). Due to this, even if the space walks where really long the maximum or minimum temperatures experienced would not be exactly that of the extreme temperatures on the moon.

I looked up the durations of space walks on the moon, a lot where really short ( 12 - 40 mins ) and i believe due to the reasons i mentioned above the movement would not have had time to reach any ridiculous temperature, allowing it work properly. some of the longer ones ( 2 hrs+ ( there where not many)) it could have come close, but I'm not certain as actually solving the math behind the equations that model this situation would take a while ( and i definitively lack 1 or two pieces of info i would need to solve it).


TLDR: the movement probably never saw the extreme temperatures mentioned above seen on the moon).

Would the hands, dial and crystal not melt or at least stop working?
 
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According to Universe Today the suits worn on the moon had internal cooling or heating bit like air conditioning. The suit could also reflect the heat away so it is possible to survive and another poster on the forum mentioned the time needed to heat and cool down also there was a lime limit regarding the walks. So it is possible that man did actually walk on the moon. HOWEVER THE SPEEDY WAS NOT IN A SPACE SUIT OR HAVE ANY TEMPERATURE REGULATION IT WAS OUTSIDE THE SUIT. HOW DID IT SURVIVE EVEN THOUGH THE WALK WAS FOR A SHORT TIME? WOULD THE HANDS, DIAL AND PLEXIGLASS JUST MELT OR FREEZE?
 
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Man can easily survive in space with the suite as it is pressurised. See this article from How it works. http://science.howstuffworks.com/space-suit1.htm But how does the watch survive? We have seen many pics from NASA with the men wearing the speedy. The current model has been shown by Hodinkee in 2014 being worn by the Russian's doing their space walk. What is the outside during EVA? Is it similar to the moon?
 
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On EVA just doing a regular space walk they have similar hazards as the moon See the U Tube clip of a modern spacewalk with 5 interesting facts. It takes 45 min to put on suit, outside they are traveling at 17,227mph, temperature variation similar to moon can vary 250 F +/-. So it seems this guy just wants attention and to become famous, like a thread we had of that kid that made a homemade clock and the cops arrested him and let him go.
 
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Thought we only ever see the one side of the moon, so there would not be a variation every 12-13 hours as the moon is always one side light and the other dark it just disappear,s as the earth turns....

But don't ask me anything about space or the moon as only have the watch, In case it is needed one day.... Other than that I'm out of this technical jumbo mumbo...

The same side of the moon (near side) is always facing the earth because it rotates on its axis at the same rate as it revolves around the earth, approx. once every 28 days. It used to spin faster but slowed to its present rate due to the gravitational drag from the earth. I love this kind of mumbo jumbo 👍
 
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The conspirator fraternity have a right to their views. But it is our duty to question their motives. Some people say, they are communists or just want to become the individual or group that became famous for proving that man in fact did not walk on the moon.
 
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The conspirator fraternity have a right to their views. But it is our duty to question their motives. Some people say, they are communists or just want to become the individual or group that became famous for proving that man in fact did not walk on the moon.

I call them dumb 😉
 
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Read this from Watch Time regarding Ed White watch.


The real test for the Speedmaster came on June 3, 1965, during the Gemini 4 mission, when astronaut Edward H. White wore the chronograph over the sleeve of his spacesuit for a spacewalk. The environment in outer space is as harsh as any a watch will encounter anywhere. Near-vacuum conditions and extreme temperatures prevail. The temperature on the side of the ship exposed to the sun climbs to about 100 C and plummets on the other side to approximately –100 C. In anticipation of these rigors, Omega developed prototypes with red anodized aluminum cases for protection from extreme temperature variations and dials coated with zinc oxide to provide the highest resistance to solar radiation. But these prototypes turned out to be unnecessary because the Speedmaster withstood the extreme temperatures without any modifications.

To read the rest of this story, plus more about the Omega Moonwatch, order the WatchTime E-Special: Omega Speedmaster.
 
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The same side of the moon (near side) is always facing the earth because it rotates on its axis at the same rate as it revolves around the earth, approx. once every 28 days. It used to spin faster but slowed to its present rate due to the gravitational drag from the earth. I love this kind of mumbo jumbo 👍

Hey that's what I said 😉