Stars · Star
A star whose effective temperature has been measured as about 4,286 K. Explore its views, where their colours came from, and palettes you can use.
Featured palette: Calculated blackbody colour at 4,286 K (Calculated from this model)
#FFD9B2
#FFD9B2About Arcturus
A star whose effective temperature has been measured as about 4,286 K.
| Classification | Star |
|---|---|
| Identifiers | α Boötis |
| Spectral type | K1.5IIIFe-0.5spectral type (SIMBAD * alf Boo; ref 1989ApJS...71..245K) · CDS, Strasbourg |
| Effective temperature | 4,286 Keffective temperature (photosphere) · Astronomy & Astrophysics / arXiv |
| Distance | 36.7 light-years ± 0.22 light-yearsdistance from parallax 88.83 ± 0.54 mas (SIMBAD; ref 2007A&A...474..653V) · CDS, Strasbourg |
Why these colours?
Calculated blackbody colour at 4,286 K
The colour a perfect blackbody at 4,286 K would have, calculated with the CIE 1931 2° observer and shown as chromaticity only, so the brightest channel is full. A real star’s spectrum has absorption lines and is not a perfect blackbody, so this is a model, not a photograph.
From: Calculated blackbody colour at 4,286 K Calculated visible-colour model
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 Arcturus.
Calculated blackbody colour at 4,286 K
Calculated from this model · Calculated blackbody colour at 4,286 K
#FFD9B2RGB 255, 217, 178region average
See where these colours came from
Creative palettes inspired by Arcturus
A design derived from the selected representation. It is not a scientific colour measurement. Each colour keeps the sampled colour it was made from.
Inspired by Arcturus
Inspired by this object
#59432CRGB 89, 67, 44from #FFD9B2#AB8863RGB 171, 136, 99from #FFD9B2#FDD6AFRGB 253, 214, 175from #FFD9B2
Colours of the first view of Arcturus with their lightness spread evenly, for a design palette.
Explore the views and the 3D model
Pick a colour from the image. Click or tap the picture to read a colour. Picked colours are yours, not catalogue samples.
Schematic sphere A plain sphere tinted with the anchor colour of the named view; it shows no surface detail and no measured shape. 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.
Sources
- Gaia FGK Benchmark Stars: effective temperatures and surface gravities (Heiter et al. 2015, A&A 582, A49), Table 9 — Astronomy & Astrophysics / arXiv (Table 9 (Fundamental Teff and log g))
- Stars in an Exoplanet World — NASA
- CIE 1931 2° colour-matching functions (CIE 018:2019, Table 6) — CIE
- SIMBAD astronomical database — CDS, Strasbourg
Image credits
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 570f202d12ab. No ESA, ESO or NASA endorsement is implied.