Olympus could have been the mountain (ah, but which Mt. Olympus?) or the heavens; if Olympus is the sky above, it made sense to say - ah, that light there, that quick one? It's the messenger god Hermes (Mercury). It's not as simple as that of course because the planets are also supposed to be the children of Eos (the Dawn) the sister of Helios (Sun) and Selene (Moon) as well as having heroic identities.
http://www.theoi.com/Titan/AstraPlaneta.html
The mother of Hermes is a good example. She was Maia, a daughter of Atlas, she had a mountain (Cyllene) but she was also part of a constellation (Pleiades). She did not die, she was a goddess who left the Earth because she was pursued by the lustful Orion. It's said that Virgo (Justice=Dike/Astraea) was the last goddess to dwell on Earth before the Age of Bronze drove her off. They'd still be watching from the sky, but they wouldn't have to interact.