Arp's Universe - A New Perspective

 Last November, I spent a few days at the Eldorado Star Party in West Texas. While there I had the pleasure to meet Dennis Webb. Dennis had recently co-authored a book chronicling Halton Arp and his peculiar galaxies. I recently received this book as a gift and I have been thoroughly enjoying it. It is a fascinating read into the life and work of Halton Arp. Now for those that do not know Arp, he is an American professional astronomer who worked with Hubble in the 50 and 60's.

Arp's started out by gathering photographs of "strange" galaxies. These were galaxies that just did not seem to fit our idea of a well organized, symmetrical design. He eventually published an atlas of 338 of these peculiar galaxies.   While a beautiful collection in itself, this alone was not Arp's claim to fame.

You see, Arp made a discovery that showed quasars had a nasty habit of showing up in close proximity to these peculiar galaxies and further more in some cases, like NGC 7603, there seemed to be a structural relationship between the galaxy and the quasar. The problem here is that the galaxy and the quasar are are vastly different distances from us. The quasar here, Object 1, is twice as far away as the galaxy, so, how can they be connected?  The distances here are measured by "red shift." This is the phenomenon that causes spectral lines to shift wave length in proportion to the velocity at which the object is receding from us. This is the same phenomenon that makes a train whistle change pitch as it passes by. The higher the red shift, z, then the faster the object is moving away from us, and in an expanding universe, the further away the object is.  So, what Arp was now suggesting, is that red shift has an intrinsic component that changes over time and thus red shift alone cannot determine distance. And here is where Arp really puts the screws to modern cosmology. If red shift cannot be used to measure distance, then there is no proof that the universe is indeed accelerating  and thus no Big Bang!
Opponents of  Arp's suggest that the quasar and NGC7603 is just a chance alignment. However, after closer examination, 2 more quasars were found, Object 2, and 3,  both of which lie along the same galactic structure connecting the galaxy to the first quasar! So if this was now a chance alignment of 4 objects then the statistical probability of that happening are "astronomically" small and Arp would argue virtually impossible.

Halton Arp has paid a professional price for his work. Because the work flew in the face of popular theory, Arp was branded an astronomical heretic by many of his peers. Tolerance for his alternate theories was non existent here in the US. Arp lost his telescope time at Palomar and became an outcast of popular astronomy. Eventually, Arp resigned from the Carnegie foundation and relocated to Europe where his alternate theories were tolerated more and he was given more freedom to pursue his research.

Well, I did not intend to give a lesson on cosmology here because I am woefully under qualified for that. What I did intend to do is to point out that our understanding of our universe may not be as complete as we had thought. Astronomers, like Arp, are utilizing observational data to refute the current theory of an expanding universe. This is not unlike what Copernicus and Galileo did many centuries ago. Arp may eventually be proven correct and his name may one day be held in the same regard as Copernicus and Galileo. Only time will tell.

Clear skies

rw