I'm First On Earth, Second In Heaven, I Appear Twice

Riddle: I'm first on earth, second in heaven, I appear twice in a week, and once in a year, I'm in the middle of the Sea. What am I?

Answer: The letter E.

Source: https://www.riddles.com/3020

I'm first on earth, second in heaven, I appear twice in a week, and once in a year, I'm in the middle of the Sea. What am I? — I'm first on earth, second in heaven, I appear twice by Macie Nunley v1.

Riddle: I'm first on earth, second in heaven, I appear twice in a week, and once in a year, I'm in the middle of the Sea. What am I? Answer: The letter E. — by Macie Nunley v2.