Posting images of galaxies in Halton Arp's Atlas of Peculiar Galaxies (1966).
Automated account. Image curation, descriptions, typos, and most alt text by human astronomer @KellyLepo.
See posts for image credits and links to the original sources.
Hubble image of Arp 94, also known as NGC 3226 and NGC 3227.
The large spiral galaxy, NGC 3227 is interacting with its elliptical galaxy companion, NGC 3226. Faint tidal streams of gas and dust link the pair, showing evidence of their mutual gravitational pull.
Credit: NASA, ESA, and H. Ford, G. Kober
Source: https://science.nasa.gov/missions/hubble/hubble-captures-a-galactic-dance/
Image of Arp 70, also known as UGC 934, from the Atlas of Peculiar Galaxies by Halton Arp (1966).
In the original catalog, it was in the category: Spiral galaxies - Small, high surface brightness companions. Like its more famous cousin M51 (Arp 85, the Whirlpool galaxy), Arp 70 is a large galaxy with two well-defined spiral arms interacting with a small companion. These interactions are linked to grand-design spiral arms.
NTT image of Arp 22, also known as NGC 4027.
NGC 4027 is a barred spiral galaxy with a single spiral arm. It is interacting with a smaller companion galaxy, NGC 4027A, which is just out of frame.
Credit: ESO
Source: https://www.eso.org/public/images/potw1030a/
Hubble image of Arp 189, also known as NGC 4651.
While not visible in this image of the center of the spiral galaxy, NGC 4651 was included in the Arp catalog because of a narrow stellar stream in its outskirts. The stream is the remnants of a small galaxy that was ripped apart as it fell into the halo of the large spiral.
Credit: ESA, NASA, D. Leonard
Source: https://esahubble.org/images/potw2013a/
Spitzer image of Arp 188, also known as the Tadpole Galaxy.
The Tadpole is a result of a recent galactic interaction. A small intruder galaxy distorted the larger galaxy's shape, creating a 280,000 light-year-long tail of stars and gas.
Credit: NASA/JPL-Caltech/C. Lonsdale (IPAC/Caltech), SWIRE Team
Source: https://www.spitzer.caltech.edu/image/sig05-019b-spitzer-swire-view-of-the-tadpole-galaxy
Image of Arp 122, also known as NGC 6040 and LEDA 59642, from the Atlas of Peculiar Galaxies by Halton Arp (1966).
In the original catalog, it was in the category: Elliptical galaxies - Close to and perturbing spiral galaxies. This pair of galaxies NGC 6040, the tilted, warped spiral galaxy and LEDA 59642, the round, face-on spiral are in the midst of a collision.
Dark Energy Camera image of Arp 289, also known as NGC 3981.
The galaxy's irregular arms are likely due to gravitational interactions with a neighboring galaxy.
NGC 3981 is a member of the NGC 4038 galaxy group. This group also contains the Antennae Galaxies, another famous example of galactic interactions.
Credit: Dark Energy Survey, DOE, FNAL, DECam, CTIO, NOIRLab, NSF, AURA, R. Colombari, M. Zamani
Source: https://noirlab.edu/public/images/iotw2425a/
Spitzer and Hubble image of Arp 142, also known as NGC 2936, NGC 2937, and UGC 5130, or the Penguin and the Egg.
In the "Penguin", dust and gas appear as red filaments at the longer wavelengths of infrared light seen by Spitzer. The "Egg" is nearly featureless and made of older stars. The lack of dust suggests it lost its reservoir of gas and dust needed to new stars.
Credit: NASA, ESA, STScI, AURA, JPL-Caltech
Source: https://www.spitzer.caltech.edu/image/ssc2018-05a-arp-142-the-penguin-and-the-egg
Sloan Digital Sky Survey image of Arp 6, also known as NGC 2537 or the Bear’s Paw Galaxy.
NGC 2537 is a blue compact dwarf galaxy. It has a nucleus that is rapidly forming stars, surrounded by a horseshoe-shaped structure that is also forming new stars. Since the stars in the nucleus are older, the horseshoe may be the result of a shockwave sent out by the nuclear starburst.
Credit: Sloan Digital Sky Survey
Source: https://commons.wikimedia.org/wiki/File:NGC2537_-_SDSS_DR14.jpg
Hubble image of Arp 185, also known as NGC 6217.
This was the first image of a celestial object taken with the newly repaired Advanced Camera for Surveys (ACS) after the 2009 Servicing Mission 4, where astronauts upgraded the Hubble Space Telescope.
Credit: NASA, ESA, and the Hubble SM4 ERO Team
Source: https://science.nasa.gov/asset/hubble/barred-spiral-galaxy-ngc-6217/
Image of Arp 15, also known as NGC 7393, from the Atlas of Peculiar Galaxies by Halton Arp (1966).
In the original catalog, it was in the category: Spiral galaxies - Detached segments. NGC 7393 is a barred spiral galaxy in the constellation Aquarius.
@ArpBot Hubble image of the same galaxy (rotated 90 degrees counter-clockwise from the main toot's image):
https://en.wikipedia.org/wiki/NGC_7393#/media/File:Arp_15_HST.jpg
Paul Drye