Both mean "after 1 year" right? Are they the same or a bit different in usage? When do you use "go" and "ato"? Example : "ato ichinen shitara Nihon ni iku" and "ichijikan go ni iku". Are they interchangable?
They might be confusing, but:
- 一年後 いちねんご ichinen go — one year after(wards); one year later
- 一年後 いちねんあと ichinen ato — one year later; one year behind
- 後一年 あといちねん ato ichinen — one year remaining; one year to go (until)
(The word あと is written in hiragana more often than not.)
So, there are significant differences between them, though I don't deny they could be used interchangeably in some situations.