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You should probably read the heat transfer primer page first.

It gets up to 280 F (138 C) on the moon.

At high noon the average temperature of the lunar surface can reach that temperature. But that's not the same thing as saying it was 72 F (22 C) in Los Angeles today. The latter is air temperature. The temperature of various surfaces in Los Angeles might have been as high as 180 F (82 C). Air temperature has no meaning on the moon because there's no air.

280 F (138 C) may be the temperature of the lunar surface material at equilibrium in full sunlight, but it's not the temperature of any random object in a similar situation. Objects will be heated to that temperature only if they absorb the same amount of sunlight as lunar surface material, and also radiate it at the same rate. More reflective objects absorb less light and are heated less. Less reflective items may be heated even hotter.

Air temperature is not the same thing as surface temperature.
Just as on earth, the temperatures at morning and evening on the moon are lower than at noon. This is because the sun strikes the surface at a more acute angle and therefore isn't as intense. The lunar landing sites and times were chosen so that the astronauts would be working there in the early morning before the temperature had risen to its hottest. This reduced the surface temperature at those sites.

The physics term for this phenomenon is "form factor for radiative heat transfer". Quite a mouthful. The meteorological term is "angle of insolation" and it's why we have seasons on earth.

Photographic film melts at 150 F (65 C). Therefore you can't use it to take photos on the moon.

This would be a problem only if there was a way for the film to be heated. Since the film wasn't in direct sunlight it wouldn't have been heated.

The only source of heat would have been conductive heat transfer through the camera body, and only at the points where the film physically touched the body or a connected part. Rolled up on its spool inside the magazine it was relatively safe from conducted heat. Hasselblad gave the lunar surface cameras a shiny polished metal finish to reduce the amount of light they would absorb.

David Groves, PhD, has shown that the extreme heat of the lunar environment would alter the colors in the film used to take the Apollo pictures. [Bennett and Percy, Dark Moon, p. 540]

Dr. Groves' study is seriously flawed.

First, Dr. Groves assumes that when NASA says the lunar surface temperature at the Apollo landing sites varies from 180 F in the sun to -180 F in the shade, this means the Hasselblad cameras and film also reached this temperature. In fact, the temperature of the lunar surface (i.e., rocks and dust) as quoted by NASA has nothing to do with the equilibrium temperature reached by other objects exposed to sunlight in the lunar environment. Since the film magazine was covered with polished aluminum it would have absorbed very little radiant energy from the sun. Further, Hasselblad confirms that additional shield plates were added to the Apollo magazines to enhance their thermal insulative properties.

Second, Dr. Groves assumes that the film was subject to constant extreme heat for an average of four hours, corresponding to the average duration of a lunar EVA. Since the only possible method of heating would be absorption from sunlight, this would require the astronauts to stand facing the sun continuously for four hours. But of course that's not what they did. They were quite active, alternating between sunlight and shadow, turning toward and away from the sun constantly.

Now a cold object placed in the sunlight will begin to warm. It will not immediately leap to its hottest temperature. Similarly, a hot object removed from sunlight will radiate away its heat and become cool again. It can take quite a while for objects to reach these various equilibrium temperatures. The magazine alternated between sunlight and shade while it was attached to the camera, and was stored away from sunlight when not attached. It is highly unlikely the magazine ever reached either extreme of its temperature band, which is not the 180 F to -180 F range quoted for the lunar rocks and dust. And the film itself was never in direct sunlight and so would have absorbed absolutely no radiant energy.

Attempting to simulate the thermal conditions of the lunar environment, Dr. Groves uses the only mode of heat transfer not pertinent to space.
Third, Dr. Groves uses an oven to heat the film. This is completely absurd. An oven uses primarily convective heat transfer: the element heats the air in the oven, and the air then transfers the heat to the material being cooked. But because there is no air on the moon, there is no such convective heat transfer. Dr. Groves has chosen the only mode of heat transfer which doesn't occur on the moon!

Without a fluid medium to convectively transfer any heat from the magazine to the film itself, only two modes of heat transfer are possible: radiant transfer from the inner surface of the magazine to the film itself (the amount of which would be small in this scenario), and conductive transfer from the magazine case through the winding mechanism to the film itself. This is a very limited path of conduction.

In any case, Dr. Groves' baking the film in an oven at 180 F for four hours is largely unrepresentative of the conditions in which the Apollo photographic film was used and stored. It is baffling to see such unsophisticated and flawed analysis issued under the guise of professional science. We struggle to understand how even the most basic principles of thermodynamics seem to find no place in Dr. Groves' study.

If film gets too cold it will crack and the emulsion will flake off. The bitter cold of space would ruin the film.

We can point out that conspiracy theorists can't agree on whether the film is subjected to intense heat or intense cold in space. But to answer the question directly we point out that the Apollo film was manufactured with Kodak's Estar base. This base is an extra-thin polyester (not celluloid) material formulated for high-altitude (i.e., cold temperature) aerial photography, especially photoreconaissance.

The magazine casings were coated with aluminum. While this would reflect away most of the light, it would absorb enough to keep the film within its operating temperature.

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