Pisces–Cetus Supercluster Complex

The Pisces–Cetus Supercluster Complex is a galaxy filament. It includes the Virgo Supercluster which in turn contains the Local Group, the galaxy cluster that includes the Milky Way. (However, a 2014 study indicates that the Virgo Supercluster is only a lobe of a greater supercluster, Laniakea.)

Astronomer R. Brent Tully of the University of Hawaii’s Institute of Astronomy identified the Complex in 1987.

The Pisces–Cetus Supercluster Complex is estimated to be about 1.0 billion light-years (Gly) long and 150 million light years (Mly) wide. It is one of the largest structures known in the observable universe, but is exceeded by the Sloan Great Wall (1.3 Gly), Clowes–Campusano LQG (2.0 Gly), U1.11 LQG (2.5 Gly), Huge-LQG (4.0 Gly), and Hercules–Corona Borealis Great Wall (10 Gly), respectively.

The complex comprises about 60 clusters and is estimated to have a total mass of 10¹⁸M_☉. According to the discoverer, the complex is composed of 5 parts:

With its mass of 10¹⁵M_☉, our Virgo Supercluster accounts only for 0.1 percent of the total mass of the complex.

The complex was named after the Pisces-Cetus Superclusters, which are its richest superclusters.

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