Image: Hubble's view of the polar ring of Arp 230

Image: Hubble's view of the polar ring of Arp 230
Credit: ESA/Hubble & NASA, Acknowledgement: Flickr user Det58

This image shows Arp 230, also known as IC 51, observed by the NASA/ESA Hubble Space Telescope.

Arp 230 is a galaxy of an uncommon or peculiar shape, and is therefore part of the Atlas of Peculiar Galaxies produced by Halton Arp. Its irregular shape is thought to be the result of a violent collision with another galaxy sometime in the past. The collision could also be held responsible for the formation of the galaxy's polar ring.

The outer ring surrounding the galaxy consists of gas and stars and rotates over the poles of the galaxy. It is thought that the orbit of the smaller of the two galaxies that created Arp 230 was perpendicular to the disk of the second, larger galaxy when they collided. In the process of merging the smaller galaxy would have been ripped apart and may have formed the polar ring structure astronomers can observe today.

Arp 230 is quite small for a lenticular galaxy, so the two original forming it must both have been smaller than the Milky Way. A is a galaxy with a prominent central bulge and a disk, but no clear spiral arms. They are classified as intermediate between an and a .

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Citation: Image: Hubble's view of the polar ring of Arp 230 (2015, February 2) retrieved 19 August 2019 from
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Feb 06, 2015
I'm bewildered that the author would mention Halton Arp's Atlas of Peculiar Galaxies, and then provide an explanation for the structure which Arp himself would disagree with.

Feb 06, 2015
Astronomers and astrophysicists have ignored Arp and his work for decades, why would they start now? The way the article is written one might think Arp himself proposed the explanation. This is typical of the obfuscation which occurs in astrophysics.

Feb 06, 2015
Thanks for demonstrating how little you know about Arp, let alone astronomy in general.. Arp collected a catalog of peculiar-looking galaxies which is regularly referenced by current astronomers, as witnessed by this very article. The controversy revolves around only a small subset of Arp's peculiar galaxies - those where two or more objects with wildly different redshifts appeared to be physically connected. Arp 230 is not one of those objects. And astronomers and astrophysicists did not ignore Arp and his work for decades. They looked at Arp's objects with great interest with generation after generation of telescope, and typically when looked at with better instruments than Arp had used, the apparent connection between the objects was not visible. Arp's theory was killed with superior data.

Feb 06, 2015
Arp just passed away last year, the reason he was unable to use the "better instruments" was because his telescope time was refused because of his obvious proof that destroyed the "standard theory". You can read about one of those in examples here;

NASA for some reason deemed it necessary to "doctor" an image to eliminate the bridge connecting the two, this obfuscation of the truth has since been exposed. Has NASA retracted? No, just as with you they continue to ignore the correction.

Arp continued to publish late into his life, and he produced more and more evidence to support his claims. It's as if you chose to ignore everything he produced after he was kicked out of Palomar.


He is known as the "modern day Galileo" and "The Most Feared Astronomer on Earth."


Feb 07, 2015
I don't suppose you appreciate the irony that you linked to an Arp article featuring an image captured by what was at the time the telescope with the best angular resolution, Hubble. Science did not ignore objects of interest. It's true he lost telescope time, but that was after a debate in 1972 in which as Tom Ferris put it, " was also difficult to feel that his case had suffered anything short of demolition." It's also telling that Arp's article fails to mention the paper by Bahcall et al, 1992 (Astrophysical Journal, Part 1, vol. 398, no. 2, p. 495-500 ) (Bahcall being the physicist to whom Arp lost the debate 20 years prior) that proved by finding absorption lines in the spectrum of NGC 4319 that it was absorbing some of the light from Markarian 205 passing through it, and therefore Markarian 205 is behind NGC 4319, not beside it. Arp's article is not a reasoned weighing of the evidence, it's a biased article by a bitter old man clinging to the scraps of a failed theory.

Feb 08, 2015
It's difficult to appreciate irony that is not there. It's a fact NASA altered the image to hide what is there, even so they failed at their obfuscation. It seems to be you that is bitter and "clings to the scraps of a failed theory (hypothesis)". Arp proved beyond a shadow of a doubt that the theologically based big bang fantasy is a fraud. Hubble himself published the notion that a single example of intrinsic or discordant redshift would be enough to falsify the hypothesis, as such astrophysicists ignore reality to this day.

Feb 09, 2015
Strange the things you call "facts." NASA stacked together a bunch of different images using a dynamic range that wouldn't lose detail in the brighter regions. This was a press release designed to show a pretty image to the public, not a release of scientific data. NASA couldn't possible have hidden anything because the raw data and the software tools to analyze it are freely available to anyone with an internet connection. Look at how ugly Jack Sulentic's version is and how much detail it destroys in other areas. In fact, note how Jack's version hides the fact that there are significant diffraction spikes from the two bright spots in Markarian 205, including some diffraction spikes that are oriented in the same direction as the "light bridge" and which in fact might be contributing to the appearance of the light bridge. Curious that Arp never mentioned those, him not being biased and all....

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