Why is Austin spelled with an オ?


Based on the pronunciations [here](http://www.saiga-
jp.com/pronunciation_voice.html), what I hear in Anime, and the way I hear
kana pronounced in Japanese class, it seems to me that Austin should start
with ア rather than オ, but it is clearly spelled with an オ
([reference](http://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%BC%E3%82%B9%E3%83%86%E3%82%A3%E3%83%B3)).
Why is this? Am I somehow seriously misunderstanding the way kana are
pronounced?

I am assuming that the reason for this has to do with cot/caught merger in
English. It seems to me that British people would very likely pronounce words
like "Austin" with the オ sound. On the other hand, I pronounce Austin much
like [this guy](https://www.youtube.com/watch?v=8buFjFAnyy4).

This issue is particularly important to me because my last name also contains
this same sound, and in class, I've been spelling it with an ア.




The main two factors in transcription from English to Japanese are

  1. (Japanese perception of) pronunciation in English
  2. spelling in English

Transcribing `au` as `オー` is the norm (note the lengthening!):

> audio オーディオ  
>  auction オークション  
>  Australia オーストラリア  
>  Austria オーストリア  
>  audition オーディション  
>  automatic オートマ (abbr.)  
>  aura オーラ

