迷失 New 问题 ... 1. How Far in the Future? 

i don't think it was that far i mean kate had hardly aged at all maybe 3-5 years

I agree...

I'm thinking it's at least three. But it could easily be more. The fact that Kate hadn't visibly aged really doesn't mean much. For one thing, we only really saw her in the dark. Also, we know that she was barely thirty on the island. Many women don't age noticeably during their 30ish years.

Then again... I could be wrong