Pioneer Anomaly

A heat radiator will not cause anything to accelerate because it is just blackbody radiation and nothing of any mass is being radiated. You can't have any action from f=ma when m=0.

Is it possible that our calculation of the transmision times is not accurate, perhaps the waves are being delayed by an unknown curvature of spacetime or elysium. If the signal is delayed from when it is expected wouldn't this cause an anomoly? Are the signal delays mathematically consistant for the two probes? Just fishing here?

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by rousejohnny</i>
<br />Is it possible that our calculation of the transmision times is not accurate, perhaps the waves are being delayed by an unknown curvature of spacetime or elysium.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">No. The spacecraft carries no clock, just a transponder. So the signal originates on Earth at a radio telescope and makes a round trip to the spacecraft and back, the travel time being measured by a single clock.

Waste heat dumping is much like the solar radiation pressure force on balloon satellites. It is a necessary component of the non-gravitational forces acting on the spacecraft. Whether it is also sufficient to explain the entire anomaly is the only point where there is still room for debate. But the fact that only nuclear-generator-carrying spacecraft have this anomaly is surely an important clue. -|Tom|-

So the signal is getting back quicker than expected and we are translating that to means they are not as far away as they should be? Just trying to keep other rational open.

What if gravity is not a constant and varies slightly. could this be the answer ?
An example of this could be the final stages of a sun's evolution: it contracts. Gravity increases.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by rousejohnny</i>
<br />So the signal is getting back quicker than expected and we are translating that to means they are not as far away as they should be?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Right. So either something is accelerating just the three spacecraft involved toward the Sun faster than the Sun can pull it, or something is speeding up the radio signals (which would have a hard time explaining Ulysses).

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by GD</i>
<br />What if gravity is not a constant and varies slightly. Could this be the answer?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Nothing else is affected except these three spacecraft. So no, nothing about gravity can possibly be responsible. -|Tom|-