What does this number measure?
A red supergiant in the Large Magellanic Cloud, surrounded by a torus of dust. The disc shown represents its diameter, twice the adopted radius of 1540 nominal solar radii (1 nominal solar radius = 695 700 km). The value is a dated estimate, not an established size record. A radius of 1 540 solar radii was estimated in 2009 after accounting for dust. This historical reference does not measure its current instantaneous state; its spectrum and surroundings evolve.
Compare the stated dimensions
The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.
Source and limitations
Radius estimate of 1 540 solar radii in 2009, after accounting for dust. This historical reference does not measure its present instantaneous state; its spectrum and surroundings evolve.
WOH G64 A: an artistic illustration of a stellar photosphere. Shared generic pattern for comparing diameters; not a photograph or a reconstruction of this star. The value and its uncertainties come from the entry.