Answer:
What two letters in the alphabet say goodbye?
They come out at night without being called, and are lost in the day without being stolen. What are they?
I'm a god. I'm a planet. I measure heat.
What falls down but is never injured?
What is something you can hold without ever touching?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.