no, you need a yahoo mail acount. Click join this group. It will ask you for you to sign in. Use your yahoo email to sign in and then select your signup options for the group. I usualy opt for no email, this way my yahoo inbox is not clutered with emails from the group.
I found the same doco on the following url by Keith Burnett
http://bodmas.org/kepler/altaz.html
This is his main page, he has a few coding examples to for various things.
http://bodmas.org/kepler/index.html#top