What are you doing 2 million years from now?

From http://www.universetoday.com/2008/04/16/the-pioneer-anomaly-a-deviation-from-einstein-gravity/
Both Pioneer probes are approximately 240,000 miles (386,000 km) closer to the Sun than predicted by calculation. Scientists have been arguing over the cause of this mysterious force for a decade and reasons for the Pioneer anomaly range from the bizarre to the sublime. Is it a simple fuel leak, pushing the probes of course? Is it phantom dark matter dragging them down? Or do the gravity textbooks need to be re-written? Unfortunately there's still no one answer, but some researchers believe there might be a small deviation in the large-scale space-time Einstein described in his famous theory of general relativity. See, I knew there would be a simple explanation…

The Pioneer 10 and 11 deep space probes were launched in 1972 and 1973, visiting Jupiter and Saturn before pushing on toward interplanetary space, into the unknown. The Pioneer program really lived up to its name, pioneering deep space exploration. But a few years on, as the probes passed the through the 20-70 AU mark, something strange happened… not suddenly, but gradually. Ten years ago Pioneer scientists noticed that something was wrong; the probes were slightly off course. Not by much, but both were experiencing a slight but constant sunward acceleration. The Pioneer probes had been measured some 240,000 miles (386,000 km) closer to the Sun than predicted. This might sound like a long way, but in astronomical terms it's miniscule. 240,000 miles is a tiny deviation after 6.5 billion miles (10.5 billion km) of travel (it would take light 10 hours to cover this distance), but it's a deviation all the same and physicists are having a very hard time trying to work out what the problem is.

That is until NASA physicist Slava Turyshev, co-discoverer of the anomaly, rescued a number of Pioneer magnetic data storage disks from being thrown out in 2006. These disks contain telemetric data, temperature and power readings that both Pioneer probes had transmitted back to mission control up to 2003 (when Pioneer 10 lost contact with Earth). From this, Turyshev and his colleagues teamed up with Viktor Toth, a computer programmer in Ottawa, Ontario, to design a new code designed to extract the vast quantity of raw binary code (1s and 0s), revealing the temperature and power readings from the crafts instruments. It sounds as if the search for the culprit of the Pioneer anomaly required a bit of forensic science.

Now the researchers have a valuable tool at their disposal. Turyshev and 50 other scientists are trying to match this raw data with modelled data in an effort to reconstruct the heat and electricity flow around the craft's instrumentation. Electricity was supplied by the on-board plutonium generator, but this is only a small portion of the energy generated; the rest was converted to heat, lost to space and warmed up the probe's bodywork. Heat lost to space and warming of the probe's instruments are both thought to have a part to play in altering spacecraft momentum. So could this be the answer?

In the mean time, Pioneer 10 is drifting silently toward the red star of Aldebarran and (barring any more anomalous behaviour) will arrive there in 2 million years time…

I for one will welcome our Alien Overlords.

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