Re: Pioneer Anomoly


"John C. Polasek" <jpolasek@xxxxxxxxxx> wrote in message
news:0k5gj1hq00rta8cv2tfkdbn2o1tsqiaf89@xxxxxxxxxx
> On 26 Sep 2005 05:47:30 -0700, "Dishman" <george@xxxxxxxxxxxxxxxxx>
> wrote:
>
>>
>>John C. Polasek wrote:
>>> On Sun, 25 Sep 2005 17:33:38 +0100, "George Dishman"
>>> <george@xxxxxxxxxxxxxxxxx> wrote:
>>> >"John C. Polasek" <jpolasek@xxxxxxxxxx> wrote in message
>>> >news:5fbdj198q5i6s0bidsjnlucl484d7vndem@xxxxxxxxxx
>>> >>
>>> >> Let's see if we can get this straight. The anomaly is strictly one of
>>> >> clock performance.
>>> >
>>> >That is your claim. Anderson et al say that it
>>> >appears the range has been affected implying
>>> >that there is a real acceleration, however, the
>>> >data is not sufficiently accurate to be certain
>>> >of that. Be that as it may, let's consider the
>>> >numbers for the possibility of a clock error.
>>> >
>>> >> This is of course a relief or we would be studying
>>> >> the planets to see why they have not strayed. There is not one iota
>>> >> of
>>> >> anomalous acceleration of the craft, so it just muddies the waters to
>>> >> argue red or blue shift nomenclature.
>>> >
>>> >The nomenclature is not significant but the
>>> >sense of the effect is.
>>> >
>>> >> I think we can agree that the arithmetic quoted in Turyshev produces
>>> >> a
>>> >> negative frequency difference implying that the reference clock has
>>> >> sped up to give the same negative frequency difference as I assert in
>>> >> the paper. That negative difference increases proportional to trip
>>> >> time. Can we agree on that?
>>> >
>>> >No. What is observed looks like an acceleration
>>> >towards the Sun. In other words the craft seems to
>>> >be leaving the solar system slower than expected.
>>>
>>> George, take another look at Turyshev,s formula. They take their
>>> frequency difference as the received frequency minus the sending
>>> frequency:
>>> Dnu = nu - nu0 <0,
>>> Without exception DNu is negative so the received signal is lower so I
>>> don't understand why you assert the opposite at the bottom of your
>>> note "No, the starting point is that the frequency received is higher
>>> than expected". Frequency increases as they proceed out of the well.
>>
>>The reason I am telling you that is because this
>>question was discussed for many months some years
>>ago in the group and the sense was determined for
>>from comments in the Anderson paper. There was a
>>crank here at the time who also argued that the
>>shift was in the sense you claim and eventually it
>>got to the point where he mailed Slava Turyshev, one
>>of the authors. Slava confirmed that the measured
>>frequency is higher, not lower and they re-issued the
>>paper stating that the DSN convention which applies
>>to all their software and consequently their values
>>is that negative numbers represent increased frequency.
>>It is rather bizarre but that's the way they have
>>always done it.
>>
>>> Markwardt in paper "Independent confirmation..." has a graph showing
>>> 1.55 hz over 4 years and another scale ~20 cm/s/4yr = 2Ap. So the
>>> valid acceleration would be 1.55Hz/8 years one way equal to 6e-9 hz/s
>>> as you said.
>>
>>Craig Markwardt was the other person involved in
>>th previous discussions. He is working on data
>>analysis on the Swift mission. He obtained the
>>raw data for Pioneer 10 and analysed it himself
>>and found the same discrepancy as Anderson et al
>>and he also confirmed that it was a higher
>>frequency than was predicted.
>>
>>Basically I am sying that we know without any doubt
>>the sense of the anomaly and it is the opposite of
>>what you are currently predicting.
>>
>><snip agreement of values>
>>
>>> >Since that speed
>>>
>>> what speed?
>>
>>You lost the previous context:
>>> >... In other words the craft seems to
>>> >be leaving the solar system slower than expected.
>>
>>I am talking of the 12k/s speed at which the craft
>>was moving away from the Sun. Simple Doppler produces
>>a redshift of about 88kHz each way because of that.
>>An anomalous acceleration towards the Sun would reduce
>>that speed hence produce less redshift, in other words
>>the anomaly contributes a blueshift. Whether it is a
>>real acceleration or a clock effect is a separate
>>question but that fact that it _appears_ as if the
>>craft is being slowed means they must be seeing an
>>increased frequency, it was just a qualitative argument
>>based on their description whicvh lets you confirm that
>>the sense of the signal is as I said.
>>
>>George
> George, you are making a lot of trouble for me with this redshift
> business. (!)

Sorry John, but you still don't get to shoot
the messenger. All this was confirmed several
years ago, long before I ever heard of you or
your theory. It's just bad luck it turns out
to be the wrong way for you.

The older discussion related to "tired light"
which predicts the same level of red shift as
the Hubble constant. The anomaly is in the wrong
direction and about 4 orders of magnitude larger
than that.

> I am very sure of my theory and point out that there are
> several places to get the sense reversed. The reason I am so sure is
> that Dual Space theory solves way way more than just the Pioneer
> problem and way way more than relativity. Anyway, to the defense.
>
> Markward's paper has a minor error where he claims ashift of +2.7 Hz
> in a single round trip, which would have to be +2.7 mHz (10^-3).

I would have to check the context but I see no
reason why that shouldn't be comparable to the
3Hz found by Anderson et al.

> There are several places to get the sense reversed. The signal
> processing is quite complicated. They use a 240/221 divider to
> downlink a different frequency, and I would imagine for simplicity and
> good "null-seeking" practice they would subject the reference
> transmitting frequency to a similar 240/221 divider before
> comparison.

Sort of, the reference against which the received
signal is heterodyned is derived digitally from
the local reference and is calculated to be a
given offset away from where the received signal
is anticipated. That calculation takes account of
the transponder ratio and the Doppler due to both
the craft speed and the speed of the Earth in orbit.

> But Markwardt says the Doppler signal (2Ghz or the beat?) is
> down-converted to a 1 Mhz intermediate frequency after which the MDA
> accumulates a continuous count of Doppler cycles for fixed integration
> intervals. It's hard to see exactly what is going on. Down-converting
> probably means heterodyning which would be OK, but frequency division
> would be self defeating.

It does mean heterodyning with a reference derived
from the local atomic clock. They work to an offset
of 1MHz to avoid the ambiguity between received
frequencies above or below the reference if they
mixed to zero. Basically it is just a 1MHz "IF" as
in any het. receiver.

> After all this, it would take careful study indeed to tell whether you
> are metering A-B or B-A.

Programming in a reference 1MHz higher instead of
lower (or vice versa) would have the effect of
turning A-B into B-A, but it is actually simple to
tell which you have. When the craft rises above
the eastern horizon, the rotation of the Earth is
carrying the site towards the craft while when it
is setting the site is moving away from it. The
received frequency should therefore fall steadily
through the contact so if the frequency is rising
you know you have your signal the wrong way up.

The same is true of the annual variation due to
the orbital speed. The only way such an error
could be missed is if the craft were 180 degrees
away from where JPL thought, and that would put
it on the wrong side of the Earth !

As you know Markwardt also independently confirmed
the sense of the effect.

> There is I believe a predisposition to think
> in terms of attraction to the sun, since both P10 and P11 on opposite
> side showed the same effect, and who would willingly entertain the
> idea of repulsioin by the sun?

The idea of a gravitational effect has never been
in favour because the effect is constant over more
than a factor of 2 in range. The most realistic
theory is that heat from the RTGs is reflected of
the back of antenna and if the effect was a red
shift Anderson et al would have noted it. In the
paper thay also state that the cause cannot be
solar radiation since that pushes the craft the
wrong way consider Fig. 6 on page 19.

> After Tuesday I can only communicate sporadically, more's the pity.

Given that you now know the anomaly is an increased
frequency rather than decreased, I guess you will
have some significant work to do on your theory
anyway to see if you can reverse the predicted sign.

George


.

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