Michael Dorman, Dallas, Texas for his question:

Where does the dew come from?

Fill a pitcher with iced water and leave it in a cool room. rretty soon the outside of the pitcher will be covered with drops of moisture. The water certainly didn't ooze out of the solid pitcher. So where did it come from?

It came from the moisture, or crater vapor, which was right there in the warm air of the room. All air holds some water vapor, and warm air holds more than cool air. In fact, when warm air is cooled it is forced to live up its water vapor in drops of moisture. The warm air of the room was cooled on the sides of the pitcher and there it was forced to drop some of its moisture.

The morning dew is formed in much the same way. Near dawn, the ground is often cooler than the damp, warm air above it. This warm , damp air touches the surface of the grass and leaves.  This cools the air close to the ground and it is forced to give up some of its water vapor in drops of pearly dew.