A remarkable galactic hybrid

NASA IMAGE OF THE DAY | NASA’s Hubble Space Telescope Showcases a Remarkable Galaxy.

Last Updated: March 6, 2017
Image credit: European Space Agency/Hubble & NASA

This NASA/ESA Hubble Space Telescope image showcases the remarkable galaxy UGC 12591. UGC 12591 sits somewhere between a lenticular and a spiral.

Pisces–Perseus Supercluster is a long chain of galaxy clusters that stretches out for hundreds of millions of light-years — one of the largest known structures in the cosmos. Its classification straddles somewhere between a lenticular and a spiral galaxy. It lies just under 400 million light-years from us.

The galaxy itself is extraordinary: it is incredibly massive. The galaxy and its halo together contain several hundred billion times the mass of the sun; four times the mass of the Milky Way. It also whirls round extremely quickly, rotating at speeds of up to 1.8 million kilometers (1.1 million miles) per hour.

Observations with Hubble are helping astronomers to understand the mass of UGC 12591, and to determine whether the galaxy simply formed and grew slowly over time, or whether it might have grown unusually massive by colliding and merging with another large galaxy at some point in its past.