ASTRO:
     type=Polar Ring galaxy
     mag=11.2
     const=Pisces
     dist=45 M ly
IMAGE:
     location=Emerrald Bay community, Lake Palestine, TX
     BrtlCls=4
     exposure=CMOS OSC; 52x300s (4.3h), G100
     palette=LRGB
EQUIPMENT:
​     optics=ES102CF APO / Hyperion 24mmEP (afocal) 1.7x, FL(eff.)=1238mm, f(eff.)/12.1
     camera=ZWO ASI2600MC-Pro
     filter=Optolong L-Pro LPS
     mount=Celestron AVX
     guiding=Orion 60x240mm, ZWO ASi224MC
SOFTWARE:
     acquisition=Stellarium, NINA, PHD2
     processing=PixInsight (RCAstro), Photoshop (APF-R, WebSharp-Pro), LrC

This peculiar and uniquely rare structure is classified as a polar-ring galaxy.  It has two different rings of stars.  Cataloged as NGC 660, it spans about 50,000 light years and is located about 45 million light years away from Earth toward the constellation of the Fish (Pisces).  The astronomical community at-large has not yet come to consensus over a common name.

NGC 660's main disk of bright stars, gas, and dust appears edge-on at a nearly 45° diagonal; while another longer ring, seen as tilted just a little away from edge-on, runs roughly horizontal across the middle.   How polar-ring galaxies obtain their striking appearance remains a topic of research, but a leading theory holds that the configuration results from the collision, interaction, and eventual merging of two (2) galaxies with different central ring plane orientations.  It is theorized this particular galaxy may have collided with another similarly sized galaxy over a billion years ago.  

The outer ring is much broader than the main galaxy disk itself, and has a greater amount of glowing nebulae and star formation occurring than the host disk does.  This likely indicates a very violent origin.  The polar-ring contains objects numbering in the hundreds, many of which are emission nebulae together with red and blue supergiant stars.  Click here for a professional, more detailed image, collected with the 8-meter Dr. Frederick C. Gillett telescope located in the International Gemini Project observatory atop Mauna Kea Volcano in Hawai'i.  The most recently created stars in the ring are approximately 7 million years old, with the difference between their age and the theorized age of the galaxy merger indicating that formation of the outer ring has been a long process.  The violent turbulence represented by the numerous nebulae and stars tends to demonstrate the process is on-going.

Scientists have extrapolated data about the dark matter contained in NGC 660's outer ring by observing the gravitational interaction between its rotation and that of the main disk.  Also, intense radio waves have been found emitting from an area inside the core region of the main disk that is only 21 light-years across.  This may indicate the presence of a super-cluster of stars located deep inside the central region of the main disk where the heaviest concentration of dust and gas exists.  That area has a vast amount of star formation going-on.  It is so luminous that the main galaxy is considered to be a starburst galaxy.

Late in 2012, this polar-ring galaxy produced an enormous outburst of light and radiation with a magnitude about 10 x brighter than a supernova explosion.  The cause is not certain, but the event may have been the result of an enormous jet being ejected from a central black hole.

The featured image was captured on a completely clear and moonless night near Tyler, TX, USA using only a simple broad-band light pollution suppression filter in front of a CMOS OSC camera.   Being an infrequently imaged object, this galaxy boasts a unique and interesting astronomical heritage.  Together with its highly unusual and beautiful configuration, it represents a prized capture for amateur astrophotographers who can find it.

251021 - NGC660 (unnamed) Polar Ring galaxy in Pisces