Arp’s Peculiar Galaxies
Page 5 of 7
Arp observations 41-50 of 70 total to date.
| Thumbnail | Title/link | Arp Category | Date Observed | Observer Description |
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Arp 168 / M32 | Galaxies with diffuse counter-tails | 2024-02-20 20:00:00 | This is a very famous galaxy mostly imaged with its dominant partner, M31. It is extremely bright. I am frankly confused where Arp saw a diffuse counter trail. I don't see it in my capture, nor do I see it in the Atlas plate, which corresponds very closely to my capture. Note I've added to the gallery a wide field view of the Great Andromeda Galaxy, captured November 16, 2023. M32 is visible behind M31 |
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Arp 176 / NGC 4933 | Galaxies with narrow counter-tails | 2024-04-16 23:55:00 | This is a tiny cluster of 3 galaxies: NGC 4933 A/B/C. B is the tail galaxy which appears to be a small elliptical galaxy viewed edge-on. A is the middle galaxy, and c is the dim little nub just west of the other 2. The two brighter galaxies are Magnitude 13, and clearly interacting. C is magnitude 18.5 and does not seem to be interacting with the others. Given it's small size, it's likely to be much futher away. |
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Arp 184 / NGC 1961 | Galaxies with narrow filaments | 2024-02-29 00:00:59 | This was an enjoyable capture, and after 40m of integration I shut things down thinking I'd done a great job. However, I hadn't focused on the peculiarity of this galaxy, which was, "Galaxies with narrow filaments". Turns out I had been fooled by the bright galactic center and disk, not recognizing that the filaments were MUCH less bright. This led me to some "heroic" processing in Affinity Photo of the saved .png image, which "just" exposes the roots of the filaments and hints at their directionality. In a perfect world I would go back and capture another 40 minutes.... |
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Arp 185 / NGC 6217 | Galaxies with narrow filaments | 2024-05-23 23:56:00 | This is a relatively large and bright barred spiral Arp galaxy, located high in the sky in Ursa Minor, and observable in almost precisely the opposite direction from the nearly full moon. Unfortunately, there was a relatively faint satellite trail that passed close to the image towards the end of the capture. The dust lanes that extend the arms of the galaxy are visible but less than might have emerged on a darker night. I was reluctant to extend the capture because the moon was continuing to rise, and it seemed to me that more time might wash out the dust lanes. The filaments are reasonably symmetrical, and fill out a classic "spiral" galaxy shape albeit with much less stellar mass than in a more mature galaxy. I guessed that this is a relatively young galaxy still actively making stars, later confirmed by the Wikipedia write-up. |
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Arp 189 / Umbrella Galaxy / NGC 4651 | Galaxies with narrow filaments | 2024-05-01 22:38:00 | This is a very bright and reasonably large galaxy, where the "handle", a faint, vertical dust lane, became evident after about 30m of integration. Clouds shut down observing after 55m. Affinity Photo processing of the .png image saved "as adjusted" in Sharpcap makes it more apparent at the cost of a much noisier background. In most other respects this spiral galaxy appears normal. It is slightly elongated vertically, and the outer arm of the spiral is slightly detached from the rest of the disc, both consistent with a gravitational attraction from the top of the image. |
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Arp 205 / NGC 3448 | Galaxies with material ejected from nuclei | 2024-04-22 23:10:00 | NGC 3448 was discovered by William Herschel in 1789. Impressive when you appreciate he was observing by eye. He did not discover UGC 6016 which is the smudge you can see in the upper part of the image, just right of center, a 17th magnitude dwarf galaxy. NGC 3448 seems to have two nuclei, which is presumably why Arp describes it as depicting "material ejected". That may be, though it seems more likely that this is the result of an incomplete galaxy merger. I find it impressive that despite the full moon, with some processing, I was able to capture not only NGC 6016 but also hints of the dust lanes connecting it to NGC 3448. |
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Arp 206 / NGC 3432 | Galaxies with material ejected from nuclei | 2024-04-21 23:15:00 | Arp 206 consists of an edge-on spiral galaxy (NGC 3432) of magnitude 11.3 interacting with a magnitude 16.3 galaxy, UGC 5983 (the little smudge to the right and slightly higher). There does seem to be a suggestion of a second interacting galaxy in the opposite direction, in the same plane as NGC 3432. Both may be represent what Arp categorizes as "material ejected from nuclei", though it seems equally likely that the materials may be in a merger process. |
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Arp 210 / NGC 1569 | Galaxies with irregularities | 2024-02-29 00:00:37 | The target emerged relatively quickly. Consider compass bearings through the galaxy, with north pointing up and to the left through the long axis of the galaxy. The central bulge is elongated along the N-S axis, and appears slightly bent on the z axis, with ends below the central plane of the disk. The southern hemisphere disk appears thick and intact. The northern hemisphere appears to have been disrupted. The disk is largely missing from W to NW, as is a smaller section from NNE to NE. Irregular indeed. |
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Arp 213 / IC 356 | Galaxies with irregularities | 2024-02-29 00:00:41 | This is a beautiful, bright galaxy, slightly elongated on the N/S axis, which appears to have a section of the outer disk, perhaps 10% of the total area, shaved from west to south. |
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Arp 214 / NGC 3718 | Galaxies with irregularities | 2024-04-16 21:30:00 | This is a striking target worth revisiting. Was enjoying watching the image build until a wall of clouds stopped the observation. With some stretching in Affinity Photo was able to capture the striking, twisted arms which were evident on the screen but less evident in the original SharpCap capture. |