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Comment by Retr0id | Hacker News Reader

The next space mission should be to leave a colour calibration chart on the moon.

They brought a gnomon, with a color chart, on the Apollo missions. They would set it up for many of the pictures of samples.

https://airandspace.si.edu/collection-objects/gnomon-lunar-a...

Here's a shot of a color chart on the moon from Apollo 17 (AS17-137-20900):

https://tothemoon.im-ldi.com/data_a70/AS17/extra/AS17-137-20...

Is there a document that explains that color chart?

This version shows different shades of colors: https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=AS17&...

The first one has been adjusted to bring out the contrast and saturation while the one you link is an original scan. They brought a number of different swatches like that and took a picture of a calibration array at the end to account for the effects of space exposure on the film.

The one I posted is from an original scan.

Doesn't mean it hasn't been altered before posting to juice the shadows and make it more vibrant. The one from NASA's site looks like an unaltered scan.

I think we are looking at different scans. See: https://tothemoon.im-ldi.com/about

The moon itself already is one. Moonshots are widely used in calibration, at least for earth observation satellites. The brightness of the full moon at each wavelength at each day of the year is predictable and well-known, so it makes a good target to check your payload against.

They also put color calibration charts on Mars rovers. For example https://www.lucideon.com/news/colour-standards-on-mars

There is even a Damien Hirst¹ haphazardly spread about the surface for that purpose.

One of the great gifts Pillinger² had was being able to shake up public interest via pop culture; there was also call sign by Blur for Beagle 2.

¹ https://www.researchgate.net/figure/Spot-Painting-Beagle-2-C...

² https://en.wikipedia.org/wiki/Colin_Pillinger

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