I've been thinking about this for a while but never got around to asking this. This has two parts. First, I understand that time and matter are closely related and that time slows down when in proximity to more matter. So, time on the moon is faster than time on earth and time on Jupiter is slower than time on earth. Second, I'm under the impression that the pioneer spacecrafts, the ones that were launched in 1973 and left the solar system are both accelerating in an unforeseen manner. Could this observed speed increase possibly be due to the lack of relative proximity to matter and time is becoming faster around the pioneer spacecrafts..hence the speed increase? Let me explain. Lets say it takes 5 seconds to cross from point a to point b at a speed of 1 kph. While it still takes the same 5 seconds to cross from point a to point b at a speed of 1 kph, say time is now faster due to lack of matter in proximity wherein 5 seconds from point a to point b is observed from earth as 3 seconds. While it still took 5 seconds to go from point a to point b, I observed from earth that only took 3 seconds b\c of the way time works, so it appeared faster. Basically, I assume this due to the causal association that time slows when in proximity to matter and the opposite in conditions of less matter..so the obvious lack of matter outside to solar system compared to within it should cause time to go faster, hence observable speed should increase from earth of any moving objects. This brings a lot of other interesting possibilities too..like if something moving at just under the speed of light in conditions where time is faster could be observed from earth as moving faster than light even though the object itself is only moving at just under the speed of light because of the way time works. Also, matter between galaxies would appear from earth as moving very very fast b\c of a relative lack of matter compared to within galaxies. Or..am i completely offbase with all this?