Chapter 25: The 'Negative' Stellar Parallax demystified

25.1 The calamitous history of stellar parallax measurement

The concept of parallax is fairly simple: it is the appearance of lateral displacement of a nearby object in relation to a more distant one as viewed by someone in motion. For instance, imagine driving down a highway and looking at the scenery through your righthand window. As you pass a tree by the roadside, it will seem to drift from left to right in relation to the background scenery. Of course, the tree is not moving in relation to the background: it is just an optical effect caused by your own motion. In astronomy, the tree and the background scenery are represented, respectively, by a layer of nearby stars and a layer of distant, so-called fixed stars. Stellar parallax is the appearance of lateral displacement of the nearby stars in relation to the distant stars due to Earth’s movement. Naturally, the effect is extremely small and difficult to observe.

"Hipparchus of Nicaea (2nd century BC) is the first known astronomer to have made careful observations and compared them with those of earlier astronomers to conclude that the fixed stars appear to be moving slowly in the same general direction as the Sun. Confirmed by Ptolemy (2nd century AD), this understanding became common in medieval Europe and the Near East, although a few astronomers believed that the motion periodically reversed itself." "The Restless Globe" - astrosociety.org (opens in a new tab)

"The annual parallax is the tiny back-and-forth shift in the direction of a relatively nearby star, with respect to more-distant background stars, caused by the fact that Earth changes its vantage point over the course of a year. Since the acceptance of Copernicus’s moving Earth, astronomers had known that stellar parallax must exist. But the effect is so small (because the diameter of Earth’s orbit is tiny compared with the distance of even the nearest stars) that it had resisted all efforts at detection." "The Techniques of Astronomy" (opens in a new tab) by James evans (2017)

Since Copernican astronomers believe our planet orbits around the Sun in a 300-million-km wide circle (see Chapter 23), they will choose a star and determine its position 6 months apart. According to their reasoning, the Earth will then have moved from one side of its orbit to the other, and so will have been displaced by its maximum elongation in relation to the stars. As they compare the two observations of the chosen star, they will calculate its parallax trigonometrically, using a baseline of 300 Mkm.

Fig. 25.1 Image source: “Stellar Parallax” - Encyclopædia Britannica (opens in a new tab)

In the TYCHOS model, however, the Earth only moves by a mere 7018 km every six months. The fact that this is a quite small displacement with respect to the distant stars helps explain why detecting stellar parallaxes was impossible in Brahe’s times and is still a formidable challenge for modern-day astronomers:

Fig. 25.2 The Earth’s motion in one year (14036 km) and in six months (7018 km). Note that north stars observed from the North Pole will still be moving around slightly trochoidal paths, due to the 23.4° tilt of the Earth’s axis.

Before we move on, an important point concerning the history of stellar parallax measurements needs to be clarified:

“It is important to notice that the early attempts were at measuring what today would be called absolute parallax, rather than relative parallax, which is the parallax of a nearer star with respect to that of a distant star”. "The Historical Search for Stellar Parallax" - by J. D. Fernie (1975) (opens in a new tab)

For centuries after the so-called ‘Copernican Revolution’, the failure of our world’s top astronomers to detect any relative stellar parallax remained a critical problem for the heliocentric theory. It was logically thought that, if Earth travels around the Sun in a 300-Mkm wide orbit, some amount of relative stellar parallax should be detectable. Yet, it wasn’t until 1838 when Bessel detected some minuscule parallax for a star called 61 Cygni (a confirmed binary system). Bessel’s observation was then triumphantly hailed as a robust confirmation of the Copernican postulate that Earth revolves around the Sun!

"At the end of 1838, Bessel announced that over a period of one year 61 Cygni made a small ellipse in the sky. The greatest displacement from the average position was just 0.31” with an error of 0.02”. This tiny motion of 61 Cygni was a direct consequence of Earth’s motion around the Sun. Bessel had finally discovered an annual parallax." "Measuring the Universe: The Cosmological Distance Ladder" (opens in a new tab) by Stephen Webb (1999)

Today, the two major official stellar parallax catalogues, ‘Hipparcos’ and ‘Tycho’, published by the European Space Agency (ESA), include the values of a few million stars. Indeed, ESA now proudly proclaims that their current ‘Gaia’ enterprise will soon provide the celestial positions and distances of a billion stars.

Now, here is the problem: in later years, a number of independent researchers patiently scouring ESA’s largest database of about 2 million stars have pointed out a seemingly inexplicable aberration: roughly 25% of the stellar parallaxes are negative, 29% are positive, and 46% are ‘assumed zero’. In other words, nearly half the stars listed in the ‘Tycho’ catalogue exhibit no observable parallax. It turns out that the confirmed existence of negative stellar parallax is a veritable death blow for the Copernican model. The reason for this should become clear by examining Figure 25.3 and Figure 25.4.

Fig. 25.3

Imagine travelling in a car orbiting ‘counterclockwise’ around the Sun, imitating the motion assigned to Earth by the Copernican theory. For the sake of simplicity, let us assume the car does not spin around itself every 24 hours. The Sun will always be shining through your lefthand window, whereas to see the stars you will always have to look out your righthand window. Thus, if you were to measure the optical effect of the nearby stars ‘moving’ in relation to the distant stars, the parallax would at all times be positive, meaning that the nearby stars would invariably seem to move from left to right (or from east to west) in relation to the background.

Yet, about one fourth of all the stellar parallaxes listed in ESA’s ‘Tycho’ catalogue have negative values, essentially meaning that they were observed to move from right to left (or from west to east) in relation to the more distant background stars. How can this possibly be?

We shall now see why the TYCHOS model provides the simplest and most logical solution imaginable to this most troublesome affair. In short, since Earth’s PVP orbit is entirely inside the Sun’s orbit, stars will actually be observable not just through the ‘righthand window’ of the orbital car in the example above, but on all sides. Depending on which ‘window’ of the cosmic car you are looking through, stellar parallaxes will be positive (~25%) on the ‘right side’, negative (~25%) on the ‘left side’, and zero (~50%) in front of and behind the car (no parallax of a nearby star can be detected if you are moving either directly towards or away from it).

Obviously, Earth does not reverse direction, so heliocentrists can only conceive of positive parallax. Negative and zero stellar parallaxes, though empirically verified by their own partisans, constitute a physical impossibility and an utterly insurmountable problem for their model.

Fig. 25.4 Why negative stellar parallax cannot exist in the Copernican model.

As a matter of fact, astronomers have for centuries been observing negative parallaxes in nearby stars drifting in the opposite direction of what the Copernican model predicts. Strangely, there is practically nothing to be found regarding this very serious problem in modern astronomy literature. The question of negative stellar parallaxes has eluded any rational explanation to this day and appears to be ‘taboo’ among today’s astronomers. Back in 1878, the famous astronomer Simon Newcomb briefly commented on this thorny issue, concluding that “such a paradoxical result can arise only from errors of observation”.

Fig. 25.5 Extract from Simon Newcomb’s “Popular Astronomy” (1878)

Perhaps the most ironic twist of the entire history of stellar parallax detection (and as very few will know) is the fact that Bessel—the man credited with making the first “indisputable stellar parallax determination that finally proved Earth’s motion around the Sun”—had initially detected and reported a number of negative star parallaxes, not only for the star 61 Cygni, but also for Cassiopeaie, while Sir James Bradley had even observed negative parallax for our north star, Polaris! Below is an extract from one of the more inquisitive, fact-filled papers by earnest astronomy historians I have come across over the years:

"But Bessel was to be disappointed again: when he had finished the reduction of the position of 61 Cygni relative to the six different stars he was forced to the conclusion that its parallax was negative! The paper in which this result was announced took the form of a report only, with no explanation of why a negative answer might have been obtained. Bessel gave tables of observations, and results of the application of the method of least squares to these observations for each comparison in turn; he followed this with exactly the same information for μ Cassiopeiae which he had compared with θ Cassiopeiae. For this star also he had a negative, though numerically smaller result. In volume III of the Konigsberg observations Bessel gave another set of observations, this time of the difference of right ascension between α and 61 Cygni from which he deduced an even larger negative result for the parallax of 61 Cygni. A different account may be constructed from Bessel's private correspondence. In a letter to Olbers written at about the time that the first set of negative results for 61 Cygni was published, Bessel stated that: "The negative parallax which one found here and there and which he had in fact found for the Pole Star from Bradley's observations was of course the result of observational errors." "Attempts to measure annual stellar parallax-Hooke to Bessel" (opens in a new tab) by Mari Elen Wyn Williams (1981)

Before proceeding any further, you should know that the entire history of stellar motion measurements reads like an almost kafkaesque novel of dire, tragicomical confusion. Since virtually all the most acclaimed astronomers of recent centuries have been ‘Copernican disciples’, they simply couldn’t make any sense of their own, conflicting stellar parallax measurements. As they compared the data of their various star observations, performed during different annual seasons, they couldn’t even make up their minds about the actual direction of a given star’s proper motion (the term ‘proper motion’ refers to a star’s own displacement in any given direction in Euclidian space). Sir Francis Baily, co-founder and four times president of the Royal Astronomical Society, was well aware of the embarrassing state of the parallax affair:

"For, in many cases, some of the greatest names have differed even as to the direction of the motion of particular stars : one making it positive whilst in the same star another considers it as negative."

In a footnote to his “Catalogue of Stars”, Sir Francis Baily mentions a disconcerting argument between Baron Zach and Nevil Maskelyne over the parallax measurements of ten stars. Zach reported positive parallaxes for all ten stars, whereas Maskelyne insisted all the parallaxes were negative!

Fig. 25.6 Sir Francis Baily’s footnote in his Catalogue of Stars "The Catalogue of Stars of the British Association for the Advancement of Science" (opens in a new tab) by Francis Baily (1845)

The comedy of stellar parallax errors extends far and wide if you are patient enough to dig it up in the specialized literature. Figure 25.7 reproduces two extracts from a paper by Eichelberger published in the famed journal Science on 7 April 1916 under the title “The Distances of the Heavenly Bodies”:

Fig. 25.7

So let’s see, if only “somewhat more than half” of those 245 stars (perhaps some 125 stars) had a measurable parallax, that means no parallax was detectable for “somewhat less than half”. And among the approximately 125 measurable parallaxes, as many as 54 were negative. This is supported by a 1912 paper published in the Astronomical Journal under the title “Results for parallax from meridian transits at the Washburn Observatory". In it is a table showing a roughly 50:50 ratio between observed positive and negative stellar parallaxes:

Fig. 25.8

But, you may now ask, hasn’t technology progressed since the early 20th century? Of course it has, so let us move on and take a look at a 1966 paper by Stan Vasilevskis (of the famous Lick observatory) titled “The Accuracy of Trigonometric Parallaxes of Stars” which shows how the four most important American observatories were puzzled and bewildered by the disturbing disagreements between their respective, meticulously gathered stellar parallax data:

"Parallaxes of the same stars determined by different observers and instruments often disagreed to such an extent that the reality of some parallaxes were in doubt. Although the homogeneity has high statistical merit, the absence of various approaches makes it difficult to investigate and explain discrepancies between various determinations of parallaxes for the same stars. There are disturbing differences, and many investigations to be reviewed later have been carried out on these discrepancies. The present paper is a review of the present material, and a consideration of the possibilities of modifications in the technique of parallax determination in view of past experience and the present status of technology." "The Accuracy of Trigonometric Parallaxes Of Stars" (opens in a new tab) by S. Vasilevskis (1966)

So, as recently as 1966, the main American observatories were mystified as to the “disturbing discrepancies” between their respective stellar parallax measurements to the point that “the reality of some parallaxes were in doubt”. Curious, isn’t it? But let us fast-forward to the present. As every professional astronomer will know, ESA claims to have attained ‘pinpoint accuracy’ in the stellar motion and parallax values given in their star catalogues. The latter are allegedly based on data collected with a telescope installed aboard the ‘Hipparcos satellite’ and, still more recently, with the help of their new ‘Gaia satellite’, at the cost of USD 1 billion.

"Observationally, the objective was to provide the positions, parallaxes, and annual proper motions for some 100,000 stars with an unprecedented accuracy of 0.002 arcseconds, a target in practice eventually surpassed by a factor of two." "Hipparcos" - Wikipedia (opens in a new tab)

Fig 25.9 The "Hipparcos satellite" - as depicted at an official NASA website (opens in a new tab)

“The Hipparcos and Tycho Catalogues are the primary products of ESA’s (the European Space Agency’s) astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993.” "The Hipparcos and Tycho Catalogues" - ESA (1997) (opens in a new tab)

In later years, a number of independent researchers have seriously questioned ESA’s catalogues of stellar parallax data, allegedly collected with a midget 29-cm telescope mounted on a tinfoil-hatted, remote-controlled satellite circling the Earth at hypersonic speeds, around an eccentric orbit ranging from 500 km (perigee) to 36000 km (apogee). We mere mortals can only wonder just how that’s supposed to work, but the more fundamental question is: since stellar parallaxes are, by definition, microscopic perspective shifts between closer and more distant stars as viewed from Earth, what purpose would it serve to collect such data from a satellite hurtling at breakneck speed in a highly eccentric orbit around our planet? Hopefully, one day ESA will deign to answer these questions. In any case, the ‘Hipparcos telescope’ was acclaimed by ESA to be a ‘roaring success’, with their claimed accuracy of stellar parallax data down to 1 milliarcsecond (0.001″). An extraordinary feat of technology or of belief? That is up to each astronomer to decide.

Whether ESA’s data were collected the way they claim or not, the most interesting fact is that their largest stellar parallax catalogue—curiously enough named ‘Tycho’—lists the parallax data for more than 2 million stars, of which about 1 million are negative! This glaring absurdity was noticed several years ago by a distinguished Italian astronomer, Vittorio Goretti, who passed away in 2016. In the last years of his life, Goretti vigorously demanded clarifications from ESA but, unsurprisingly, his demands were met with deafening silence. Goretti pointed out that:

“As a matter of fact, about half the average values of the parallax angles in the Tycho Catalogue turn out to be negative! The parallax angle, which is one of the angles of a triangle, is positive by definition.”

Aside from the issue of negative parallaxes, Goretti also had some serious questions concerning ESA’s evident cherry-picking of the stars and stellar parallax data selected for publication in their far smaller show-case ‘Hipparcos’ catalogue of about 118000 stars. The ‘Hipparcos’ catalogue contains far fewer negative star parallaxes and so is claimed to be ‘more accurate’ than the larger ‘Tycho’ catalogue. Goretti also questioned how a 29-cm telescope could possibly have achieved the formidable accuracy advertised by ESA:

“The Hipparcos Catalogue stars, about 118,000 stars, are a choice from the over 2,000,000 stars of the Tycho Catalogue. As regards the data concerning the same stars, the main difference between the two catalogues lies in the measurement errors, which in the Hipparcos Catalogue are smaller by about fifty times. I cannot understand how it was possible to have such small errors (i. e. uncertainties of the order of one milliarcsecond) when the typical error of a telescope with a diameter of 20÷25 cm is comprised between 20 and 80 milliarcseconds (see the Tycho Catalogue). When averaging many parallax angles of a star, the measurement error of the average (root-mean-square error) cannot be smaller than the average of the errors (absolute values) of the single angles.” "Research on Red Stars in the Hipparcos Catalogue" (opens in a new tab) by Vittorio B. Goretti (2013)

Short of denouncing ESA for outright fraud, Goretti nonetheless suggested that the scientific community should urgently address the many issues raised by ESA’s catalogues, such as the flagrant cherry-picking and the evident misrepresentation of stellar parallax data, ostensibly aimed at concealing the high incidence of stars exhibiting negative parallax.

As we have shown, there is no room for negative stellar parallax in the Copernican model. The hypothesis that Earth is revolving around the Sun implies that all stellar parallaxes must be positive. So what mathematical devices have heliocentrists resorted to to account for the existence of officially observed negative parallax so far? A senior lecturer in astronomy at UCL London submits this ‘statistical explanation’:

“If you have a list of parallaxes of very distant objects, so that their parallaxes are on average much smaller than your limit of detection, then the errors of parallax are distributed normally, with a bell-shaped curve plotting the likely distribution of values around a mean of nearly zero. Hence we expect there to be approximately half of those published parallaxes with values less than zero and half with values more. Negative values are unphysical, but form the part of the statistical distribution of values that happen to lie below zero when the mean is close to zero.” SpaceBanter Forum (opens in a new tab) by Mike Dvoretsky (2016)

According to this reasoning, since most stellar parallax angular measurements are minuscule (“even smaller than the optical limits of detection”), the fact that half of them are negative can be predicted by a bell-shaped curve of statistical distribution. If this were the case, why would ESA even go to the trouble of publishing stellar parallax figures? If the published negative parallax figures are allegedly useless ‘false negatives’ imputable to the error margins of the instruments being larger than the observed parallax itself, why would the positive parallax figures be any less useless or any more trustworthy? If, as proudly announced, ESA has achieved the stunningly small error margin of only 1 milliarcsecond, none of their excuses for the abundance of negative parallaxes in their catalogues makes any sense.

In later years, a number of geocentrists have also commented on the negative parallaxes published by ESA. While they can give no alternative explanation for the occurrence of both positive and negative parallax values, being on the ‘other side’ of the debate gives geocentrists a certain valuable perspective:

“I believe that conventional astronomical community are in open fraud because they completely ignore negative parallax readings, explaining them away as measurement errors, at the same time as they happily use positive parallax readings to ‘prove’ their theories in opposition to geocentrism. That is intellectual skulduggery of the worst kind in my view and is basically a lie. If negative parallax readings are ‘errors’ then what cause do we have to assume that positive parallax readings are not themselves also ‘errors’.” "Negative Stellar Parallax: Proof of Geocentrism and a Smaller Universe" - forums.catholic.com (2010) (opens in a new tab)

“The Hipparcos satellite recorded that 50% of the parallax readings were negative which is not possible. In one of the biggest cover ups in scientific history the readings were ‘adjusted’ (or I would call it cooked) to make them all positive”. "Please provide a Geocentric diagram" - The Thinking Atheist Forum (2013) (opens in a new tab)

25.2 Positive, negative and zero stellar parallax in the TYCHOS

Many researchers have pointed out that ESA’s ‘Tycho 1’ catalogue actually features three distinct categories of stellar parallaxes: positive, negative and ‘assumed zero’. The latter category actually makes up nearly half the sample (46%).

“Over 1 million objects are listed in the Tycho Main Catalogue, and they state: ‘The trigonometric parallax is expressed in units of milliarcsec. The estimated parallax is given for every star, even if it appears to be insignificant or negative (which may arise when the true parallax is smaller than its error). 25% have negative parallax, 29% positive parallax and 46% assumed zero parallax.” "Amateurs measuring parallax" - CosmoQuest X Forums (2014) (opens in a new tab)

ESA’s massive ‘Tycho 1’ catalogue distributes stellar parallaxes into three distinct groups:

• Positive parallax : 29%

• Negative parallax : 25%

• 'Assumed zero' parallax : 46%**

Anyone blessed with the gift of patience and basic math skills should be able to verify for themselves what Vittorio Goretti and others discovered, namely that the stellar parallaxes recorded in ESA’s ‘Tycho 1’ catalogue are indeed distributed as described above.

We shall now see that the coexistence of positive, negative and zero parallax makes perfect sense within the spatial perspective of the TYCHOS model. Figure 25.10 shows not only why these three different categories of stellar parallax must occur, but also why they should be distributed approximately as given in ESA’s ‘Tycho 1’ catalogue:

Fig. 25.10 Expected distributions of stellar parallaxes in the TYCHOS model

As shown in Figure 25.10, the existence of about 1 million non-positive stellar parallaxes in ESA’s ‘Tycho 1’ catalogue is compatible with the TYCHOS model’s cosmic configuration. Astronomers will measure the parallax of any given nearby star against clusters of fixed stars as Earth slowly moves from ‘left to right’ by 7018 km every six months. Depending on which of the four quadrants is observed, nearby stars will appear to drift by different amounts and directions, if at all. In all logic, nearby stars located in the lower quadrant of Figure 25.10 will exhibit positive parallax, whereas nearby stars in the upper quadrant will exhibit negative parallax. On the other hand, nearby stars located in the left and right quadrants of Figure 25.10 will exhibit little or no parallax because Earth is moving either away from or directly towards them. Actually, as we shall soon see, it gets a little more complicated than that since parallax measurements will also depend on the time frame chosen for the observation.

The biggest question elucidated by the TYCHOS model is perhaps why almost half the stars listed in ESA’s main catalogue exhibit little or no parallax (what ESA refers to as ‘assumed zero’ parallax). Figure 25.11 makes it clear why this would be fully expected under the TYCHOS model:

Fig. 25.11 The TYCHOS explains why almost 50% of the stars exhibit no parallax

Provided the 6-month time window chosen to observe star parallaxes spans from March to September (or vice versa), nearby stars located in the two opposed ‘equinoctial quadrants’ will exhibit no detectable parallax for the simple reason that Earth will be either approaching or receding from them. In the TYCHOS model, the ‘equinoctial quadrants’ will invariably be in front of and behind Earth’s direction of travel along the PVP orbit. This can be readily verified and understood by perusing the Tychosium 3D simulator.

Fig. 25.12 should clarify why the whole question of stellar parallax depends on the time window chosen to measure a given star’s lateral drift against the more distant stars and thus why the history of stellar parallax measurements has been haunted by confusion and polemic. To give a practical example, let us assume that two astronomers (Joe and Jim) want to measure the parallax of Sirius. Joe chooses period ‘A’ (21 March 2000 at 00:00 > to 21 Sept 2000 at 00:00) and Jim chooses period ‘D’ (21 Sept 2000 at 00:00 > to 21 March 2001 at 00:00). This is what each one would conclude:

• JOE: Sirius has moved in a given direction by a ‘factor’ of 4

• JIM: Sirius has moved in the opposite direction by a ‘factor’ of 1

Fig. 25.12 Stellar parallaxes will vary depending on the time window chosen for their determination

Note that if Joe and Jim had instead chosen to measure the parallaxes of the stars Zavijava and Kruger60, they would probably have agreed that those two stars exhibit no parallax at all. Yet, if they had chosen to observe Zavijava and Kruger60 in different time frames, such as B (August > December 2000) or C (December > April 2001), they would both have detected some amount of parallax for these two stars. In fact, depending on the time window chosen, endless combinations of parallax discrepancies are possible, causing Joe and Jim constant torment and head-scratching.

Also, note that the above Joe vs Jim example (with its 4:1 ratio) is an extreme case, and that the average rate of variation between different measurements should probably be closer to 3:1 or so. Well, it so happens that, back in the days when stellar parallax detection was the most vividly debated topic among astronomers like Bessel, Hooke, Bradley, Struve, Huygens, Herschel, Cassini, Maskelyne, Lacaille and Lalande, their first obvious choice of a star to measure was Sirius due to its brightness. All their parallax measurements were in fact conflicting, as documented in the literature, but of special interest to us here is their stated maximum and minimum values for Sirius: 8″ and 2.5″ (although the latter was said to be ‘in the wrong direction’!).

"In the early 1760s the vexing problems of parallax were tackled once more, this time by Nevil Maskelyne in England and Jerome Lalande in France. Both based their work on observations made at various times by the French observational astronomer the Abbe de Lacaille, who published in 1758, in his Fundamenta astronomiae, the observations he had made of Sirius from the Cape of Good Hope during 1751 and 1752. (...) The star in which he was especially interested was Sirius, the brightest star in the heavens. From Lacaille's observations he calculated that its annual parallax could be as much as 8", a surprisingly high value for Maskelyne to consider likely in the light of Bradley's conclusion in 1728. (...) He finished his brief "history" with some remarks about Lacaille's observations both from the Cape and from Paris. Of the observations used by Maskelyne he said: "... but these observations of Sirius only go from the Summer of 1751 to the following Winter; and there could have been some local cause which had produced in these observations the differences of 8". After thus disposing of Lacaille's Cape observations, Lalande referred to a series of observations made at Paris between the summer of 1761 and early 1762, during which time Sirius appeared to have been displaced by a more realistic 2.5"; but this displacement could not be owing to parallax because it was in the wrong direction." "Attempts to measure annual stellar parallax - Hooke to Bessel" - by Mari Elen Wyn Williams (1981) (opens in a new tab)

The highest value (8″) recorded by these eminent astronomers was roughly three times greater than the smallest value (2.5″), in good accordance with the TYCHOS model‘s expected discrepancies that would arise depending on the time windows chosen for their observations. It is no wonder that stellar parallax measurements have caused so much confusion and controversy among observational astronomers since the adoption of the heliocentric paradigm.

25.3 Negative stellar parallaxes are not going away

So where are we today with regard to the spiny question of negative stellar parallax? Has ESA finally resolved this vexing problem with their latest ‘GAIA’ space telescope, which they now claim has a most formidable astrometric accuracy of 0.000025 arcseconds?

"Gaia is able to record simultaneously several 10000s images mapped on its focal plane. About one billion stars, amounting to ≈ 1 percent of the Milky Way stellar content, are expected to be repeatedly observed during the nominal 5-year mission, with a final astrometric accuracy of 25 µas at G = 15 mag. (1 µas = 0.001 mas = 10−6 arcsec)." Source: "Distance To The Stars" - Caltech.edu (2018) (opens in a new tab)

Apparently not! The extract below from the ‘GAIA data release 2’ report discusses at length the issue of negative parallax and how to ‘deal with it’:

"As discussed in Sect. 3.1, negative parallaxes are a natural result of the Gaia measurement process (and of astrometry in general). Since inverting negative parallaxes leads to physically meaningless negative distances we are tempted to just get rid of these values and form a “clean” sample. This results in a biased sample, however." Source: "GAIA DATA RELEASE 2" - aanda.org (2018) (opens in a new tab)

Clearly, negative stellar parallax is still today a major torment, even for the world’s best-funded astronomy institutions. One can only imagine the headaches and sleepless nights this must give the earnest astronomers and astrophysicists employed by ESA and NASA as they try to ‘justify’ or ‘explain away’ this persistent and inconvenient aberration which keeps producing “physically meaningless negative distances”.

The below screenshot from the ‘GAIA data release 2’ report bears testimony to the fact that the exasperating negative stellar parallax ‘mystery’ that has haunted astronomers for the last few centuries is not going away.

Fig. 25.13 Extract from the ‘GAIA data release report’ (2018)

In the introduction of the above-referenced report, we may read the following recommendation:

"This paper is highly recommended in order to gain a proper understanding of how to use and how not to use the astrometric data. As a simple and striking example: a small number of sources with unrealistic very large positive and very large negative parallaxes are present in the data. Advice on how to filter these sources from the data analysis is provided in the Gaia DR2 documentation."

In other words, astronomers are being ‘highly recommended to filter out any unrealistic data’ to be found in the modern stellar parallax catalogues compiled with astrometric measurements allegedly performed by the ‘ultra-precision’, multi-million dollar GAIA satellite. One could compare this to a gambler striking “0” on the roulette wheel and being told by the croupier: “Sorry Sir, in this casino we don’t consider zero a realistic number. You lose”.

We can only hope that knowledge of the TYCHOS model will some fine day put the staff at ESA and NASA out of their misery. The longstanding ‘mystery’ of negative stellar parallax is fully elucidated by the Solar System configuration of the TYCHOS model, which predicts the coexistence of positive, negative and zero stellar parallaxes distributed at a ratio of 1:1:2, just as has been empirically observed in the last few centuries by astronomers all over the world.