Hera
Zeus' sister and simultaneously wife (second, albeit),
Hera (Roman Juno) is the goddess of marriage
and protectress of females in general. 
She is also sometimes referred to as the queen of
Heaven, as her cult was an old and originally independent one.
Indeed, her celestial presence is constantly reinforced by the
Milky Way, which by Greek legend came from Hera's breasts in an interesting
episode with infant Herakles. Hera's venerable status is
reflected in her imagery, where she usually appears as a majestic woman with a crown or
a diadem, sometimes draped. And yet, none of this solemnity would seem to
stop her from exhibiting occasional petty
behavior - like jealousy towards Herakles, or complete partiality for the Achaians in their
quest for Troy.