Hint, This Is Something With One Letter

Riddle: I am first on Earth, Second on Heaven, You see me twice in a week, but once in a year, what am I?

Answer: Letter E.

Source: https://www.riddles.com/index.php/6444

I am first on Earth, Second on Heaven, You see me twice in a week, but once in a year, what am I? — *Hint, this is something with one letter* by Chloe M. Barth v1.

Riddle: I am first on Earth, Second on Heaven, You see me twice in a week, but once in a year, what am I? Answer: Letter E. — by Chloe M. Barth v2.