Moons · Moon
Io’s yellows, oranges and blacks come from the most volcanically active world in the Solar System.
Featured palette: Galileo true-colour global view (Sampled from this image)
#C4B763#CFC468#B2A350#F0E585#93803D#6B5729
Credit: USGS, JPL & Caltech; colour from a Galileo global mosaic.
About Io
Io, a moon of Jupiter, has hundreds of volcanoes. NASA notes that its varied colouring may come largely from molten sulfur and its compounds, and that sulfur dioxide is the main gas of its thin atmosphere.
| Classification | Moon |
|---|---|
| Parent body | Jupiter |
| Mean radius | 1,821.5 km ± 0.5 kmmean radius · NASA JPL Solar System Dynamics |
| Orbital period | 1.76 daysorbital period around Jupiter · mean elements, epoch 2000-01-01.5 TDB · NASA JPL Solar System Dynamics |
Why these colours?
Sulfur colours
Galileo’s true-colour global image shows Io’s mustard yellows and orange-browns.
From: Galileo true-colour global view Approximate visible appearance
Colour clusters describe pixels in an image; they cannot identify a mineral, a gas or a physical temperature. Shares of pixels describe the sampled region of the image, not the object’s surface.
Colours from selected views
Palettes sampled from identified images and regions, or calculated from a documented model. These values describe each image or model, not one permanent colour of Io.
Galileo true-colour global view
Sampled from this image · Galileo true-colour global view
#C4B763RGB 196, 183, 99region average#CFC468RGB 207, 196, 10433% of the region#B2A350RGB 178, 163, 8026% of the region#F0E585RGB 240, 229, 13320% of the region#93803DRGB 147, 128, 6114% of the region#6B5729RGB 107, 87, 417% of the region
See where these colours came from
Global texture (NASA 3D Resources)
Sampled from this image · Global texture (NASA 3D Resources)
#AF9761RGB 175, 151, 97region average#B18744RGB 177, 135, 6823% of the region#906836RGB 144, 104, 5421% of the region#C3AC56RGB 195, 172, 8621% of the region#D6D293RGB 214, 210, 14714% of the region#694B2ERGB 105, 75, 4612% of the region#B0B09DRGB 176, 176, 1578% of the region
See where these colours came from
Creative palettes inspired by Io
A design derived from the selected representation. It is not a scientific colour measurement. Each colour keeps the sampled colour it was made from.
Volcanic Sulfur
Inspired by this object
#D6C409RGB 214, 196, 9from #CFC468#B8A215RGB 184, 162, 21from #B2A350#FAE510RGB 250, 229, 16from #F0E585#997F07RGB 153, 127, 7from #93803D#715506RGB 113, 85, 6from #6B5729
Io’s yellows made bolder for an energetic palette.
Explore the views and the 3D model
Galileo true-colour global viewApproximate visible appearanceGlobal texture (NASA 3D Resources)Enhanced visible colourPick a colour from the image. Click or tap the picture to read a colour. Picked colours are yours, not catalogue samples.
Sphere with a global map A sphere carrying a global map; the shape is a sphere, not a measured shape, and the map’s own coverage gaps are shown as they are. Objects are enlarged or scaled for inspection unless stated otherwise.
Use these colours
Every palette above opens in the palette generator. With JavaScript you can also add colours to your cosmic palette, save them, make a gradient or pattern, preview them in a design or a room (you choose which colour goes on which surface), check digital accessibility and export them. Each colour keeps the view and sample it came from.
Paint matches compare digital swatches for design inspiration. They are not physical equivalents of light from space. Edits create a new design palette. The original representation remains unchanged.
Questions about Io’s colours
Why is Io yellow?
NASA suggests sulfur and its compounds account for much of the colouring, though the exact materials are still studied.
Sources
- 3D Resources — NASA
- Global image of Io true color — NASA
- Global texture (NASA 3D Resources) — NASA 3D Resources
- Planetary Satellite Physical Parameters — NASA JPL Solar System Dynamics
- Planetary Satellite Mean Elements — NASA JPL Solar System Dynamics
Image credits
- Galileo true-colour global view: NASA/JPL/University of Arizona. NASA media (not copyrighted; see the NASA image and media guidelines). Resized for the web from the publisher’s file (sha256 f1a43acff908a77a9dd89ef0e23dfcce79dbee9ccb4ce209bf1111da4d72fead).
- Global texture (NASA 3D Resources): USGS, JPL & Caltech; colour from a Galileo global mosaic. NASA 3D Resources (free, without copyright; NASA media guidelines). Resized for the web from the publisher’s file (sha256 79239daa0ac6438d02a7b536f3eb8d044098b8cf33c8f2f91dbab4f5f054bfa7).
Images were resized once for the web; colours were measured from the published files (k-means in OKLab, pcke-oklab-kmeans-1); calculated colours use the CIE 1931 2° observer. Facts last reviewed 25 October 2026. Catalogue pcke-cosmos-2026-10-25, page revision 953cdf71a50b. No ESA, ESO or NASA endorsement is implied.