I’ve just read that the final attempt to contact the Pioneer 10 spaceprobe has failed. The probe actually hasn’t been heard from since the year 2000, but this month the Earth moved into a position more favorable for picking up a signal, if there was one, and the folks at JPL (the Jet Propulsion Laboratory, which built and operated the Pioneer and Voyager probes) were hopeful. Their failure to detect anything indicates that the little ship either doesn’t have enough power left to run its transmitter, or its power systems have failed entirely. In any event, this was the last time any attempt at contact will be made.

I find myself rather saddened by this news. Pioneers 10 and 11 were originally launched in the early ’70s, bound for Jupiter, but like the plucky Mars rovers that are still operating years after their sell-by date, they endured far longer than they were intended. Pioneer 11 went on to explore Saturn after its Jupiter mission, while Pioneer 10 headed for the outer system. In 1983, it became the first human-made object to pass beyond the orbit of Pluto. These probes and their sisters, the Voyagers, have been like a recurring motif throughout most of my life; every few years, I’d read somewhere that we were still receiving their faint signals from the distant darkness, and I’d feel some little measure of pride to know what our tiny little species had done, as well as wonder that they were still out there. But now the Pioneers are both dead, just two more chunks of space debris silently coasting towards interstellar space.

Oddly, they both seem to be slowing down for reasons scientists can’t explain. A quick overview of the so-called Pioneer Anomaly as well as a rundown of their earlier exploits can be found here. Oh, and just a little bit of mind-boggling trivia for you. According to the Planetary Society Weblog,

…in order to try to make contact [with Pioneer 10], [JPL scientists] first needed to uplink a command to Pioneer 10 to transmit. So they uplinked the signal on March 3. The two-way light time between Earth and Pioneer 10 is just about one full day, so they had to wait one full Earth rotation, until the night of March 4, to listen and see if Pioneer 10 replied. It’s that far away.