NGC 1097

NGC1097, also known as Arp 77, is a nearby SBb galaxy with a Seyfert nucleus and a bright starburst ring. It has long been studied across a range of wavelengths due to its extraordinary properties. In the optical the complex nucleus, almost certainly harbouring a super massive black hole, central bar and spiral arms are well defined.

The above pseudocolor infrared image, from Herschel SPIRE data, shows similar structures that define regions of warm gas that follow the spiral arms. What is perhaps surprising is there is no evidence of the satellite galaxy typically seen around the northern most arm, but this may be in part to the image resolution.

Also evident in this image is a strong infrared background of various distant source and a number of faint features that may simply be image artefacts.

A couple of interesting science papers have been published based on spectral line analysis of various elements of the galaxy with the full array of instruments on the Herschel spacecraft:

• Far-infrared line imaging of the starburst ring in NGC 1097
• Mapping far-IR emission from the central kiloparsec of NGC 1097

The full nature of NGC 1097 is greatly debated and an interesting summary on some of the more controversial aspects can be found on the Weblore site.