The only functioning probes that far into deep space
Here are some other Web sites showing just how much valuable deep space science the Voyagers are contributing to with their unique positions beyond Pluto:
http://web.mit.edu/afs/athena/org/s/space/www/voyager/voyager_science/voyager_science.html
http://books.nap.edu/books/0309091861/html/index.html
