Understanding 「家へ帰る間に、傘を忘れてきたのに気づいた。」

Question

Consider

家へ帰る間に、傘を忘れてきたのに気づいた。

While going home, I noticed that I had come without my umbrella.

Questions:

1. Just clarifying: のに here is not meant as a conjuctive (meaning "although", "despite"), correct? Instead it's being used as 「(((傘を忘れてきた)の)に)」, correct? That is, first の nominalizes 傘を忘れてきた, and then に is tacked on the end to be used adverbially with 気づいた.

2. Is 「傘を忘れてきた」considered a subordinate clause in this sentence? If so: since it's in the past tense, does that mean that it is happening in the relative past of when the main verb (気づいた) is happening (so that the 忘れてきた happened even earlier than the 気づいた)? Or are they both uttered with the reference point being the present moment (as in English)?

Answer 1

1. Yes.
2. Yes it's a subordinate clause, and 忘れてきた is in the relative past. It becomes relative present when describing something that happens on his way home.
   • 雪が降っているのに気づいた。
     I noticed it was snowing.
   • 傘を忘れているのに気づいた。
     (ている for continuation-of-state)

Note that the use of 間に is not natural here. You can say 家に帰っていると or 家に帰る途中で.