Arp 214: Largest Galaxy in Ursa Major Cluster & Its Features

 Arp 214, or NGC 3718, is a spectacular galaxy nestled 52 million light-years away in the Ursa Major constellation. The renowned astronomer, William Herschel, brought it to light on April 12, 1789. This celestial body is an integral part of the Ursa Major Cluster, a constituent of the Virgo Supercluster, which also houses our very own galaxy, the Milky Way.

Morphology of Arp 214

Holding the title of the largest galaxy within its local cluster, Arp 214 boasts an impressive disk scale length, dwarfing its counterparts. However, defining its morphology is a challenge. It could potentially be a spiral or lenticular galaxy. It features a dust lane that streaks across its nucleus and exhibits a warped s-shape, speckled with young blue star clusters. It's speculated that the unusual shape of Arp 214 may be a result of gravitational interactions with its neighboring galaxy, NGC 3729, a spiral galaxy located 150,000 light-years away.

Optical Image of Arp 214

The image below offers a composite optical glimpse of Arp 214, captured by the 17-inch telescope at Heaven's Mirror Observatory. Crafted using broad-band filters (RGB) and a narrow-band filter focused on ionized hydrogen (Hα) emissions, the image showcases the dominating presence of Arp 214. To the right of the image, NGC 3729 is visible. At the top, the Hickson Group 56, a compact group of five interacting galaxies located 400 million light-years away, is on view.

Image Credit: Martin Pugh (Heaven's Mirror Observatory)