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Astronomy

The Handling of Image Data from the Hubble Space Telescope

Quick fact

Hubble's iconic images are not photographs but processed data—raw photon counts (as electron numbers) from CCD detectors, which scientists correct for instrument noise and cosmic rays before turning the numbers into the colorful astrophotos we see.

Why this is interesting

You've seen Hubble's breathtaking images—but did you know they aren't photographs? The camera data is just numbers, and turning them into pictures is a whole art and science.