Arp 187

Arp 187 is a radio galaxy and merger remnant located in the constellation Eridanus. It is an interacting galaxy pair. It is included in the Atlas of Peculiar Galaxies in the category galaxies with narrow filaments.
The galaxy has two prominent radio lobes, however the emission of its AGN in X-ray is low, and so is the thermal output of the AGN torus as observed in infrared, suggesting that it has been quenched. The detection of a narrow line region with still active emission mean that the AGN was still active up to at least 10^4-5 years ago. In the nucleus of Arp 187 is predicted to lie a supermassive black hole (SMBH) with estimated mass around 6.7 × 10⁸. Further observations of such a SMBH with a quenched AGN were published in 2019.