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Epitaph for a Maverick Astronomer

Epitaph for a Maverick Astronomer


Astronomer Halton Arp (1924-2013) represents an excellent example of how mainstream scientists protect their favoured explanations against anyone, no matter how qualified or prestigious, who dares to question the majority position. We see how actual observations made by Arp and colleagues, were/are not allowed to call the Big Bang origins theory into question.

The Big Bang, as an explanation for the origin of our universe, was developed in the 1940s and 1950s. It was based on the observation that light spectra from many objects in space, are shifted toward the lower energy (red) end of the spectrum.  Comparisons of the distance of some galaxies from us, estimated on the basis of other measurements, suggested that the most distant galaxies had more extreme redshifts. This suggested that the redshift is an indication of how far and how fast bodies are moving away from us and thus that everything in space is moving apart. From this, the idea of a big bang was developed. Not everybody however liked the idea of a beginning to everything. Other individuals supported the idea that the universe is eternal (steady state).

Major controversies between the Big Bang and the Steady State groups became apparent in the 1960s when some astronomers began to make observations which suggested that the redshift from objects in the sky might not indicate speed of moving away from us. The redshift, of course, was the key observation which, coupled with other estimates of distance for galaxies (such as apparent brightness), led to the idea of expansion of the universe following a Big Bang event (billions of years ago).  However in 1961 the team of Geoffrey and Margaret Burbidge measured the redshifts of a close cluster of galaxies called Stephen’s Quintet. The redshifts of the components turned out to be quite different from each other. Were these objects actually closely clustered together or not? The redshifts, if they were a correct indication of distance would suggest not.  Other similar examples have been discovered such as Seyfert’s Sextet.

In 1963 the discovery of quasars caused great excitement. These small points of light (like stars), actually exhibit huge redshifts. This suggests that they are extremely far away. To be visible at all, they must be emitting seemingly impossible amounts of energy. Did this discovery cause the Big Bang idea to be rejected because of the improbable implications of the theory? Some people did question the nature of the redshift.

Halton Arp was a young atheistic supporter of the Steady State view of the universe. Looking for an original research topic, he began to compile a list of unusual or disturbed looking galaxies. In 1966 he published his Atlas of Peculiar Galaxies.

At first Arp looked for a possible relationship between some peculiar galaxies and known radio sources. He focused particularly on a type of elliptical galaxy with disturbed spiral galaxies nearby, the latter of which looked as if they had been ejected from the elliptical body. Among possibly ejected objects he found five quasars. He concluded that the quasars are particularly associated with nearby disturbed galaxies. He published an article about this in Nature in 1966. Soon prominent astronomers declared that his sampling method was biased and that it was risky to claim close association just because objects are located close to one another in the sky. They called this situation “apparent proximity.”

Obviously a demonstration of some clear connection between objects was needed. In 1971 Arp published a photo of a luminous connection between the low redshift galaxy NGC 4319 and the much higher redshift Markarian 205. Some astronomers admitted to observing a luminous bridge but declared that it merely resulted from other objects nearby, not involving the quasar. Others declared that they saw no bridge. In the late 1980s Arp found archived X-ray data which demonstrated a connection between the two bodies. However as late as 2002, the Space Science Institute issued a press release and picture declaring that there was no bridge. The print however was underexposed and when properly developed , the bridge was clearly evident. Science on October 11, 02 published statements on both sides, but only his friends supported Arp. Many consider this pair of objects the defining issue in the controversy. However Arp’s studies have moved way beyond that one example. In the interim however, his career suffered some serious setbacks.

In 1972, under the auspices of the American Association for the Advancement of Science, Arp and John N. Bahcall (1934-2005) debated the merits of Arp’s observations. Bahcall quoted astronomers who claimed there was no bridge and he ridiculed the arguments of his opponent. Many astronomers consider this the final nail in the coffin of Arp’s views. Obviously there was a conflict between what Arp was documenting and what the supporters of the Big Bang wanted to hear. Arp argued, for his part, that he was under no obligation as a research scientist, to confine his conclusions to within the framework of the mainstream position.

The objective of the minority of astronomers (who rejected the redshift as an indicator of distance), was to obtain a fair hearing. The objective of the majority was to bring closure to the debate so that the unanimity of the public face of science could be re-established. Thus in 1983 a committee of the National Research Council in the US declared that there was no strong theoretical reason to doubt the cosmological nature of the redshifts or to believe that a new approach to physics was required.  No matter how numerous or detailed Arp’s observations were, these would be ignored. As prominent astronomer Martin Rees of Cambridge remarked: “the universe is full of peculiar coincidences. As the number of observations increases, you expect to find more peculiar effects.” (quoted in Sky and Telescope January 1995 p. 12)

In 1983 Arp’s viewing time at the Palomar Observatory was terminated, and the next year his access to an observatory in Chile, was likewise terminated. In 1985 he moved to the Max Planck Institute for Astrophysics in Germany. He was now unable to make any direct observations of the sky. However other sources of information such as the Roentgen Satellite (ROSAT), a joint US-UK-German project, would soon come into operation (1990-1999). X-ray data from ROSAT soon provided interesting information.

In August 1994, at the twenty second General Assembly of the International Astronomical Union, Arp presented data which showed galaxies with their strongest energy generating centres extended in the direction of closely adjacent quasars, also strong X-ray sources. Most fascinating was a map of the Virgo Cluster which showed a broad X-ray filament extending to the famous quasar 3C 273, a considerable distance of 10 degrees in the sky. Evidence found since 1966 has demonstrated that this brightest of quasars is located in the centre of the Local Supercluster (even although the quasar’s  redshift is 52 times larger). The  Hubble Telescope unexpectedly discovered that clouds of gas with various redshifts stretch up to the quasar. Arp however pointed out that it was “unlikely that there would be ten times as many clouds of various redshift all stretched out just behind the Virgo Cluster reaching in the direction of the far background 3C 273.” (“Rebuttals” on Arp website)   In Arp’s opinion the evidence rather supports the idea that there is material of different redshifts in the Virgo Cluster as well as the quasar.

In 2001 Halton Arp and colleagues published papers on several cases where an object with low redshift is connected to one or more objects with high redshift. These sophisticated discussions involved documentation of connections in radio waves, visible light, X-rays and also infrared (heat). There have been many similar studies.

In 2004 a quasar with a large redshift was discovered in the low redshift active galaxy NGC 7319 in Stephen’s Quintet ( a group that had previously aroused interest even before quasars were discovered). This quasar is situated near the core of the galaxy, but based on its redshift, the quasar should be thirty times farther away. The quasar was first detected by the ROSAT X-ray satellite and found to be closely connected with the nucleus of the spiral galaxy NGC 7319. Geoffrey Burbidge informed the January 2005 meeting of the American Astronomical Society that the quasar is close to the centre of the galaxy, only 8 arc seconds away from the nucleus. Despite the dense and dusty nature of the galaxy, the quasar does not appear to be shrouded by interstellar gas. This makes it unlikely that the quasar is behind the galaxy. Also a jet of matter is seen to connect the active nucleus of NGC 7319 with the quasar, suggesting that the latter was ejected from the galaxy.

In a lecture in Poland in September 1973, Arp declared that only one case of redshift discordant with the Big Bang would be enough to force a crucial confrontation between observation and the current physics. Of course no such re-examination of the cause and significance of the Big Bang ever happened. As Arp’s observations became more and more sophisticated, mainstream scientists have ignored his results. Many are afraid to even cite his work for fear of becoming the target of reprisals themselves. (Science 249 July 6/90 pp. 14-15)

So what is the significance of Arp’s legacy as far as we are concerned? For a start, it is evident that Arp’s fellow astronomers were simply not interested in his results. New theories were developed such as “gravitational lensing” to explain how distant bodies could appear much closer to us than they really are. This idea is a popular tool in observational astronomy today, but Arp’s detailed studies in various wavelengths of energy, would seem to rule out that explanation. At the very least, his research should be accorded careful consideration.

So Halton Arp, the atheist Steady State astronomer, has died. We regret his passing because of his courageous defence of his observations. We do not applaud his Steady State interpretations, which were certainly strange. The observations themselves however merely call the cosmological interpretation into question. It certainly can’t hurt to review reigning paradigms in terms of observations that don’t fit. Of course neither Big Bang nor Steady State really has any meaning for a universe which is only thousands of years old. But we do want to see scientists free to study nature even when they do not support the mainstream position on origins, or climate change, or anything else. That is Halton Arp’s legacy, he fought for the right to study nature as it is, paradigm or no paradigm.

Margaret Helder
April 2014

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