Where is the Alta Vista search engine (www.altavista.com)?

Why do you get Yahoo search engine when you type URL www.AltaVista.com? It wasn't doing that a week ago. I understand Yahoo owns Alta Vista, but I've had Alta Vista as my default search engine, and also I've been using Alta Vista since 1997. Back then Alta Vista's search engine used to compete with Yahoo and it was far superior to Yahoo's search engine. It was the top search engine on the net back then way before Google came along, and that is why I have always preferred it. I have always gotten better search results using Alta Vista than I get from using Google or Yahoo. I do not want to use Yahoo. Even though it appears Yahoo search engine and Alta Vista have been combined into the same single product, I want my Alta Vista back.