Poineer spacecrafts are slowing down....

www.planetary.org...

Interesting read.......the spacecrafts are actually slowing down and scientists don't know why......

[edit on 2-2-2006 by ferretman2]

Here's a really good thread that discussed this about half a month ago:

The Pioneer Anomaly

Maybe I'm just dense, or maybe everyone else is - but shouldn't they be slowing down? I mean, the amount of gravimetric strength behind them would be way more powerful than the gravimetric strength ahead of them, no? In this case, gravity should be pulling them back to our solar system - like a kind of comet (say Hale-Bopp) which only enters our solar system once every thousand years or more.

I think I would be more distressed if the spacecraft were SPEEDING UP - because that would indicate a sizable mass ahead of it which could fall under the category of planet - like a dark gas giant (so far that we can't see the light reflected off it)... although perhaps not very giant. It would be a most interesting find.

Maybe I'm just dense, or maybe everyone else is - but shouldn't they be slowing down? I mean, the amount of gravimetric strength behind them would be way more powerful than the gravimetric strength ahead of them, no?

You are correct that gravity would have less of an effect as the pioneer craft get further away from the solar system. What has scientists baffled is that current gravitational theory cannot explain the rate at which they are slowing. Either gravity is misunderstood by scientists or some other force(s) are acting on the pioneer probes, such as radiation, undiscovered bodies of mass, or that sort of thing. Perhaps the probes have been crashing into small particles of dust and rock (more than anticipated) slowing them down? Bottom line is, scientists aren't sure (yet) but I look forward to the explanation when they find it; it will probably be quite interesting.

The good news is at this point the space craft are still expected to stay above excape volisty .
To leave the solor system.