Javascript that displays different page every hour needs to open in new window

I have javascript on my page which opens a different page every hour of the day. This example uses a text link in the code. It opens in the same window it is displayed on. Works fine except I need it to open the click result in a new window. I’d like to keep it really simple code wise. I’d also like to use graphics as the link instead of text.

Any suggestions?

RightNow = new Date();
document.write("<a href='" + RightNow.getHours() 
  + ".html'>NON PASSKEY ENTRANCE</a>")

I’ve tried numerous ways trying to put a target in the code, and I’ll either break it where it will not show on the page at all or it still opens in the parent. Tried calling it as a function too without success.