What does this number measure?
A young group of stars visible in the constellation Taurus. The Pleiades are an open cluster. The bluish veils often depicted around its stars correspond to light reflected by dust.
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
Catalogue order of magnitude; a source is provided, but this measurement has not been individually audited.
Pleiades: interpretation of the cluster and reflection wisps; the arrangement of members and the boundary are indicative.