Newly identified galactic supercluster home to Milky Way

Our Milky Way galaxy now has a new address - it lies on the edge of a cosmic supercluster dubbed "Laniakea"!
Astronomers have determined that our Milky Way galaxy is part of a newly identified ginormous supercluster of galaxies, dubbed 'Laniakea', which means 'immense heaven' in Hawaiian.
The so-called Laniakea Supercluster is 500 million light-years in diameter and contains the mass of one hundred million billion Suns spread across 100,000 galaxies.
"We have finally established the contours that define the supercluster of galaxies we can call home," said lead researcher R Brent Tully, an astronomer at the University of Hawaii at Manoa.

"This is not unlike finding out for the first time that your hometown is actually part of much larger country that borders other nations," Tully said.
Superclusters are among the largest structures in the known Universe. They are made up of groups, like our own Local Group, that contain dozens of galaxies, and massive clusters that contain hundreds of galaxies, all interconnected in a web of filaments.

Though these structures are interconnected, they have poorly defined boundaries.
By using the US National Science Foundation's Green Bank Telescope (GBT) and other radio telescopes to map the velocities of galaxies throughout our local Universe, the researchers were able to define the region of space where each supercluster dominates.

The Milky Way resides in the outskirts of one such supercluster, dubbed Laniakea, whose extent has for the first time been carefully mapped.
The study also clarified the role of the Great Attractor, a gravitational focal point in intergalactic space that influences the motion of our Local Group of galaxies and other galaxy clusters.
Within the boundaries of the Laniakea supercluster, galaxy motions are directed inward, in the same way that water streams follow descending paths toward a valley, researchers said.
The name Laniakea was suggested by Nawa'a Napoleon, an associate professor of Hawaiian Language and chair of the Department of Languages, Linguistics, and Literature at Kapiolani Community College, a part of the University of Hawaii system.

The name honours Polynesian navigators who used knowledge of the heavens to voyage across the immensity of the Pacific Ocean.
The study is published in the journal Nature.