Question: 1 billion years is equal to how many years?
Answer: A billion years (109 years) is a unit of time on the petasecond scale, more precisely equal to 3.16×1016 seconds. It is sometimes abbreviated Gy, Ga ("giga-annum"), Byr and variants. The abbreviations Gya or bya are for "billion years ago", i.e. billion years before present.