The Milky Way is not travelling through an empty universe alone. It belongs to the Local Group, which sits near the Virgo Cluster inside a much larger region of galaxies known as the Laniakea Supercluster.
Laniakea is sometimes described as a giant island of galaxies. That image is useful only up to a point. The supercluster is not a solid object with a visible edge. It is a map of galaxies and their motions, drawn from the way gravity changes the otherwise smooth expansion of the universe.
What is the Laniakea Supercluster?
An international team led by University of Hawaiʻi astronomer R. Brent Tully proposed the name Laniakea in a 2014 paper published in Nature. The Hawaiian word is commonly translated as “immense heaven” or “spacious heaven.” The name reflects both the scale of the structure and the connection to Hawaiʻi’s tradition of navigating a vast sky.
Keep exploring
Continue with Curiosmos
The team described a region about 160 megaparsecs across—roughly 520 million light-years—with a mass on the order of 1017 Suns. Those numbers are estimates tied to the team’s definition of the region, not the dimensions of a sharply bounded cosmic body.
Where is the Milky Way inside it?
The Milky Way belongs to the Local Group, a small collection that includes Andromeda and many dwarf galaxies. The Local Group is part of the broader neighbourhood around the Virgo Cluster. That cluster, in turn, sits within the flow field used to define Laniakea.
It is helpful to picture the structure as nested maps rather than a set of boxes. Earth is inside the Solar System; the Solar System is inside the Milky Way; the Milky Way is inside the Local Group; and the Local Group is part of a much larger pattern of clusters, filaments and voids.
How did astronomers draw its boundary?
Galaxies do not simply sit still while space expands. Their local motions are altered by the gravitational pull of nearby concentrations of matter. Astronomers can measure a galaxy’s redshift and distance, then estimate how much of its motion is due to cosmic expansion and how much is a local gravitational drift.
Tully’s team used those “peculiar velocities” to identify a basin of attraction: a region in which galaxy motions follow a common large-scale flow. The boundary of Laniakea is therefore dynamical. It marks a change in the direction of the flow rather than a fence that could be photographed.
Where does the Great Attractor fit?
The Great Attractor is a concentration of mass toward which many nearby galaxies appear to be moving. It is not a single black hole waiting at the centre of the supercluster. It is a broad region containing clusters, filaments and dark matter whose combined gravity influences the surrounding flow.
The Great Attractor lies within the Laniakea flow field. Our earlier guide to the Great Attractor explains why the phrase is useful but can also create the wrong picture. Nothing is being pulled through space toward a cosmic drain. The galaxies are moving within an expanding universe while responding to unevenly distributed matter.
Is Laniakea a real structure?
Yes, in the sense that the galaxies and their motions are real measurements. But Laniakea is not “real” in exactly the same way as a galaxy or a star. Different definitions of a supercluster can produce different boundaries, and later surveys may redraw the map as distances and velocities improve.
That does not make the idea arbitrary. Scientific maps often describe patterns that emerge from a chosen measurement. Weather systems, watersheds and tectonic plates are not marked by lines in nature either; their boundaries help us organise observations and test explanations.
What lies beyond Laniakea?
Laniakea is part of an even larger cosmic web. Galaxies gather in groups and clusters connected by filaments, while enormous voids contain far fewer galaxies. On the largest scales, this web is shaped by gravity acting on matter across billions of years.
The supercluster also gives a more accurate sense of our place in space. The Milky Way is not at the centre of Laniakea, and Laniakea is not at the centre of the universe. It is one region in a much larger distribution with no privileged central point.
Why the map matters
Before the Laniakea study, astronomers already knew that galaxy clusters formed large patterns. The work mattered because it connected those patterns to motion. Instead of drawing a boundary from brightness or proximity alone, the researchers asked how galaxies travel through the cosmic landscape.
That shift turns a list of galaxy clusters into a physical story. Laniakea is the part of the cosmic web whose galaxies share a broad flow around us. The map may change as the data improve, but the underlying lesson remains: our home galaxy is embedded in a moving, structured universe.
Putting our address in perspective
Laniakea is the large-scale supercluster region that includes the Milky Way’s Local Group and nearby galaxy clusters. It spans roughly 160 megaparsecs by the 2014 Nature definition and is identified through galaxy motions. It has no hard outer wall, and the Great Attractor is a broad concentration of mass within its flow field—not a single cosmic object.
Visualising the supercluster
The earlier Curiosmos version of this guide included the image below. It remains useful as a visual record, but the text and sources now live in this updated guide.
