The tango's the dance of lovers. It's a subtle game between two passionate souls who spin and turn by their mutual forces of attraction, without yielding, until they finally succumb and the two become one.
Now look at the two souls on my sketch. They're two reasonably small galaxies, some 26 million lightyears away from us. On the left lies NGC672, our gentleman who's leading the dance, slightly larger than his female partner on the right (IC1727). Both are very active and passionate galaxies with a large and bright central bar. NGC672 shows very delicate spiral arms, the upper one of which points to the lady on the right.
IC1727's leaning backwards, in a classical quebrada movement. She's still resisting, but the attraction of NGC672's too strong. Her spiral arms have become twisted, irregular, the ends bending towards her lover. They're ready for the final encounter but it won't be a happy end. They'll have one last spin and then the bond will be broken. The centrifugal force of the scissors movement will break the magical embrace of dark matter that's connecting the two. IC1727 will do a pasada and then swirl away behind NGC672. Unfortunately, the two won't become one as is the case with the Flying Ghost Galaxy. But the tidal forces of the close encounter will mix up the matter in both galaxies so much that they'll be bursting with new stars.
A one-night stand... but a lot of new life...
Isn't astronomy romantic? :-)