The Pleiades is an open star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology. The Pleiades is a white star cluster that is roughly 500 light years from Earth.
Blue Blood Origin. The term blue blood originated in Spain. It was used to differentiate between people with light skin from those with darker complexions. The veins of southern Europeans appeared more blue due to their pale and translucent skin. Wealthy landowners or their descendents were part of an upper class in Spain that were called blue-bloods or blue-blooded.
This term refers to European Royal nobility and is a metaphor that describes the profound blue appearance of the veins and skin. The term Blue Blood (aka sangre azul) has origins that may predate recorded history. It is very certain a number of factors may have created this term. Queen Elizabeth I, less than real life portrait where the artist was challenged by the very Blue skin and veins. See the temples and the hands for more detail.