The BBC's Did nuclear spy devices in the Himalayas trigger India floods contains the following image and caption.


  1. What scientific equipment and which plutonium battery is this?
  2. Since this weighs six times more on Earth than on the Moon, why are they making Lovell carry this unlikely looking contraption around a parking lot the "surface of the Moon"?

Apollo 13 Commander Jim Lovell carrying a plutonium battery and scientific equipment during training (NASA)

Apollo 13 Commander Jim Lovell carrying a plutonium battery and scientific equipment during training (NASA)

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    $\begingroup$ Parking lot? Look at the top of the left box and go left. Look at the top of the vertical part on the right and go right. I see craters. Craters in a parking lot?? Space suit + film camera + craters -- you don't need to know anything about the incident to figure out that's a simulated moon surface. $\endgroup$ Commented Feb 25, 2021 at 0:37
  • $\begingroup$ @LorenPechtel ya I know, see the wording of item #2 :-) I think the construction of that surface warrants a new question of its own! $\endgroup$
    – uhoh
    Commented Feb 25, 2021 at 0:39
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    $\begingroup$ @LorenPechtel Sounds like you're just lucky to live somewhere with well-maintained roads. Some councils around here would just call that "localized significant potholes" and plan to resurface in five years (if there's budget to spare). :) $\endgroup$
    – TooTea
    Commented Feb 25, 2021 at 8:43

1 Answer 1


The black thing on the right is a SNAP-27 RTG. and the box on the left is an ALSEP (Apollo Lunar Surface Experiment Package) that it powers.

Here's a picture of the ALSEP for Apollo 12:

Apollo 12 ALSEP

And here is Alan Bean attaching it to the RTG with the antenna to make the barbell object in your original image:

Alan Bean deploying ALSEP

As to the second part of the question, it is clearly a training mock-up which would have had an Earth-appropriate weight, and they're probably checking that someone who is suited and booted can actually deploy it. Who knows why they did it in the car park though. Maybe it was a nice day and everyone else fancied a bit of fresh air.

The training mock-up is referenced here, which says

The Apollo 12 crew was the first to deploy a full ALSEP array and experienced a few problems carrying the packages out to the deployment site. For example, the whole pallet tended to rotate, especially the pallet containing the RTG power supply. The crew commented that the necessity to grip the carry bar tightly was tiring to the hands. On Apollo 14, Mitchell commented that the bouncing sub-pallets at the end of the barbell made it very difficult to carry and that he ended up carrying it across his arms. It seemed considerably heavier than he anticipated since the 1/6th g lightweight mock-up didn't respond in the same way.

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    $\begingroup$ Clearly not a car park (there is one in the background though). The surface is rough and uneven (note the mounds above the ALSEP) and seems to be reasonably similar to the Moon surface in the other images. The building and car park are elevated; the surface in the foreground may be water covered after rains. $\endgroup$ Commented Feb 24, 2021 at 16:44
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    $\begingroup$ "the 1/6th g lightweight mock-up didn't respond in the same way." If they used a 1/6 weight mockup for the Earthside exercises, it would take the same effort to lift as the full-weight unit would on the moon, but it would have 1/6 the mass, so it would be much easier to move horizontally, taking 1/6 the force to start or stop its motion, 1/6 the torque to rotate, etc. $\endgroup$ Commented Feb 24, 2021 at 17:21
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    $\begingroup$ @RussellBorogove I had wondered if the golf club things were a way to mess with the moment of inertia to make handling the lightweight mockup more realistic, and decided that they'd be too irritating for every other aspect of a test/training run for that to be a reasonable explanation. $\endgroup$ Commented Feb 24, 2021 at 18:19
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    $\begingroup$ This was a training exercise "in the dry", but it would have made more sense to carry out this kind of training in the water tank, since a one-sixth mock-up of the equipment lacks both mass and, consequently, momentum. Nothing on the Moon has the same weight, in the one-sixth gravity; but every thing retains the same mass and hence inertia. Once set in motion, mass has a definite tendency to behave differently where there is 6 times as much of it. Apollo training was partly in the water, to simulate free-fall. It might have made sense to include this deployment exercise in the tank too. $\endgroup$
    – Ed999
    Commented Feb 25, 2021 at 3:31
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    $\begingroup$ @Ed999 it still seems like it would fail to represent the inertia well... it might even be worse, given that the object would exhibit a lot of drag in water. $\endgroup$ Commented Feb 25, 2021 at 10:45

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