CNN reporting on Pioneer 10 falls silent after nearly 31 years:
What was apparently the spacecraft's last signal was received January 22 by the Jet Propulsion Laboratory's Deep Space Network. At the time, Pioneer 10 was 7.6 billion miles from Earth; the signal, traveling at the speed of light, took 11 hours and 20 minutes to arrive.
The signal and the two previous signals were very faint. The Deep Space Network heard nothing from Pioneer 10 during a final attempt at contact on February 7. No more attempts are planned.
Pioneer 10 has about 2 million years of travel left before it reaches Aldebaran in the Taurus constellation. The probe did it's job well and then some. NASA is to be congratulated for the success of this probe and many others, but now it's time for the behemoth to get out of the way and let the free market share some of the burden and rewards of space exploration.