Where the Pioneer probes are and information on the Kuiper Belt
Here are the current locations of the Pioneers and Voyagers in deep space:
http://www.heavens-above.com/solar-escape.asp
And this paper - Anomalous Acceleration of Pioneer 10 and 11:
Dust Density in the Kuiper Belt
http://www.newtonphysics.on.ca/Anomalous/Acceleration.html
And this BBC item from 1999 may be of interest:
http://news.bbc.co.uk/1/hi/sci/tech/460095.stm
Relevant information on the Kuiper Belt:
http://www.lpl.arizona.edu/faculty/malhotra_preprints/ISP_Nov04.html
http://www.lpl.arizona.edu/faculty/malhotra_preprints/04-TPF_Darwin.pdf
