Disturbance in the ‘force’: Did passing galaxy cause ‘Polar Ring’ NGC 660’s shape?
A rare galaxy type, polar ring galaxies have a substantial population of stars, gas, and dust orbiting in rings strongly tilted from the plane of the galactic disk. The bizarre-looking configuration could have been caused by the chance capture of material from a passing galaxy by a disk galaxy, with the captured debris eventually strung out in a rotating ring.
The violent gravitational interaction would account for the myriad pinkish star forming regions scattered along NGC 660’s ring.
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