A spectacular image of Jupiter, its rings and several moons from the James Webb Space Telescope (JWST) was recently released.

When looking at JWST images it is useful to remember that the camera is sensitive in the range of 0.6 (orange) to 5 (mid-infrared) microns. The human eye is sensitive to the range of 0.38 (violet) to 0.75 microns (red)- remember ROYGBIV? Image colors with a wavelength shorter than orange, 0.6 micron, green, blue and violet, are therefore a false color representation. In fact, all of the colors and intensities are chosen with both Hubble and JWST images. NASA is up front about this and an explanation can be found here.

A pet peeve of mine with the recent first radio image of a black hole (Sgr A*) has been that the colors represented are necessarily false, but left unexplained. This is well known to astronomers and other pointy-headed space weenies but not to the flat-headed public. The object may well be orangish from some nearer distance, but the reconstructed radio image we see is processed by software and intentionally given a visual color chosen by some person. This is fine, but a sentence or two about colored radio images is a lost opportunity for greater insight into instrumentation and the properties of light.

Alright, I’m sorry- I exaggerate. The public isn’t flat-headed. Okay? Is that better?