This Arp object is a pair of interacting spiral galaxies located about 120 million light years away in the constellation of Virgo at a declination of -6 degrees. Inclined spiral galaxy NGC 5426 is on the bottom and face-on spiral galaxy NGC 5427 is on the top. Both galaxies are about 2.3 arc-minutes in apparent diameter, which corresponds to a diameter of 85,000 light years. The galaxies are amazingly similar in their structure.  NGC 5427 shows VV rows while NGC 5426 does not.

This has always been one of my favorite pairs of interacting galaxies.  A classic look, in my opinion - 2 distant disks connected by an obvious star stream.  Perfect!  All of the sources, including NASA, talk about the classic interaction that we see here.  As the NASA site says, "Their mutual gravitational attraction has already birthed many new stars. These young stars are visible in the faint bridge connecting the two galaxies, located at the bottom of the image. Such a bridge provides an avenue for the two galaxies to continue sharing the gas and dust that become new stars." 

But I am not so sure about the extent of the interaction here, and particularly the bridge.  Over the past years as I have looked at hundreds of interacting galaxies, I have learned that true intense interactions are usually much messier that what we see here.  The distance data is a bit inconsistent over the years but generally shows the 2 galaxies to be at least 5 million light years apart.  Look at this more detailed image from the  3.6-metre New Technology Telescope at ESO's La Silla Observatory in Chile:

My eyes see 2 superimposed galaxies, the bottom (NGC 5426) slightly in front of the top (NGC 5427).  Surely there are disturbance effects seen and there is some interaction occurring, but the oft-mentioned bridge looks consistent in color with NGC 5427 and not a result of 2 connected galaxies in the midst of the merger process.

Many times, especially for Arp objects, 2 adjacent galaxies are more likely to be superimposed than they are to be merging.  Most of the Arp objects that Dr. Arp designated as "companions" were located nowhere near their supposed host galaxy.  The case here is not that extreme - they are close enough to be interacting - but I don't believe that the bridge is as exciting as I once thought it to be.  Still, an interesting and fascinating object.

Many other tiny but colorful faint galaxies are visible throughout the background.