On May 8, 5:46 pm, dlzc wrote:
Dear Alberito:

On May 8, 7:42 am, Albertito wrote:



On May 8, 3:35 wrote:
On May 8, 7:11 am, Albertito wrote:
On May 6, 10:34 wrote:
...
From that point of view, we'd wrongly conclude
that the Earth is not where it should be. IOW,
we would observe the Earth from a Pioneer
probe as orbitally decaying toward the Sun.

No, following your "model", the Sun and all the
planets you are passing also are anomalously
accelerated away from you (Sunward).

That's what I said, an anomalous acceleration
toward the Sun.

Dude, did you read what I wrote? The Sun is
acclerating away equally fast. How can the
Earth "orbitally decay towards the Sun", if the
Sun is also accelerated away?

Well, there is a point called barycenter. We
would wrongly deduced from that Doppler effect
that both the Earth and the Sun are decaying
toward solar system barycenter.

The Earth Sun barycenter is well inside the Sun, to the tune of a few
hundred meters (I think). The acceleration the Pioneer spacecraft is
experiencing would have consumed that distance by now.


Yes, I take the signs right. My original post was
just the hypothesis of anomalous gravitational
Doppler shifts. Of course, we still don't know the
cause of Pioneer anomaly. Maybe, it is only
systematics. But, there is a possibility of new physics.
If the cause is gravitational, then we have an interesting
issue here. The possibility of anomalous gravitational
shifts shouldn't be rule out.

Now remember, we "saw" the Pioneer spacecraft getting anomalously
*closer*, not further. Did you get your signs right in the initial
post?

That would be only apparent *closer*, not real, if the cause is
*anomalous* gravitational shifts.