Zooming in on Apollo 14

By on April 11, 2012 in

Apollo 14 Resolution Example

Apollo 14 Resolution Example / ©NASA/GSFC/ASU, Compilation S. Robbins

On Monday, I posted about the new Apollo 12 and 14 images that will be going up shortly on the MoonMappers site. In the post, I talked a bit about image resolution, and how in August of last year, the Lunar Reconnaissance Orbiter craft dipped down to a 25-km-high orbit and photographed the Apollo sites at 2x the pixel scale it had done before.

I thought it might be interesting to take a look at what effect this has. While that orbit was 2x better for imaging, the initial orbit of the craft was 2x higher than the normal orbit. This means we have images at about 1 meter per pixel, 50 cm per pixel, and 25 cm per pixel.

I put together a compilation to show this. In the sequence, the pixel scale is native – there has been no compression nor expansion. It’s the same Apollo 14 site. Same camera. I also tried to match the sun angle — they’re all between 45° and 55°. All that’s changed is the number of pixels you get per unit length or area due to the orbit of the spacecraft.

I think this is pretty neat, and it really shows you the kind of difference and the level of detail that we get from different spacecraft orbits. You can build a great camera, but if you stick it too far away from what you want to capture, you won’t be able to see much.

I especially like the difference you see between the top and the bottom images. I focus on the crater in the ~7:30 position. In the 1.06 m/px image, you see a small crater with a bit of a white region around it. In the 0.27 m/px image, you see that this crater is not perfectly circular, and its floor has something “going on” with it. It looks like it may have some infill, some slumping on the walls. You never would have known this from the first image.

You can also see that what looks like hot pixels is actually a boulder. Take a look at the bottom image just under the “7” in the “0.27 meters/pixel.” You’ll se a white square that one might think is just a hot pixel that didn’t get removed in processing. But, it looks like it has a shadow (to the left of it). If you go back up to the top image, you can see this same white speck in the same location that I would have dismissed as a hot pixel.

And of course, there’s also the detail you see in the Apollo lander and the astronaut foot tracks!

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