"Uncle Jimmy, we're studying Norse mythology and I keep forgetting some of the names, can you help?" Andrew asked.

"Certainly," Jimmy replied, "let's pick a few to start with: Odin, his wife Frigg, Thor, and Tyr. You really already know these names, or at least the Anglo-Saxon equivalent.
Woden is the Anglo-Saxon equivalent of Odin, the wise, one-eyed, chief god.
Frige is the Anglo-Saxon equivalent of Frigg, the goddess of clouds and sky.
Thunor is the Anglo-Saxon equivalent of Thor, the god of thunder.
Tiw is the Anglo-Saxon equivalent of Tyr, the god of war and battle."

"Sorry, but those names don't seem any more familiar," Andrew protested.

"What if I told you those four names are related to the sun, the moon, and the planet Saturn?"

"What? That's even more confusing."

"Final clue, they are the basis of a naming system that we use every day."

In what way are these names commonly used about which Andrew should be aware?