Laniakea Supercluster
The Laniakea Supercluster (/ˌlɑːni.əˈkeɪ.ə/; Hawaiian for "open skies" or "immense heaven") is the galaxy supercluster that is home to the Milky Way and approximately 100,000 other nearby galaxies.
| Laniakea Supercluster | |
|---|---|
A map of the Laniakea Supercluster and its component galaxy clusters | |
| Observation data (Epoch J2000) | |
| Constellation(s) | Triangulum Australe and Norma (Great Attractor) |
| Right ascension | 10h 32m |
| Declination | −46° 00′ |
| Brightest member | Milky Way (mag –5.0) |
| Number of galaxies | 100,000–150,000 |
| Parent structure | Pisces–Cetus Supercluster Complex |
| Major axis | 520 million ly (159 Mpc) h−1 67.80 ± 0.77 (H0 from Planck 2013) |
| Redshift | 0.0708 (center) |
| Distance | 250 million ly (77 Mpc) h−1 67.80 ± 0.077 (Great Attractor) (H0 from Planck 2013) |
| Binding mass | 1×1017 M☉ |
| Other designations | |
| Local Supercluster, Laniakea, Laniakea Supercluster, Laniakea Complex | |
It was defined in September 2014, when a group of astronomers including R. Brent Tully of the University of Hawaiʻi, Hélène Courtois of the University of Lyon, Yehuda Hoffman of the Hebrew University of Jerusalem, and Daniel Pomarède of CEA Université Paris-Saclay published a new way of defining superclusters according to the relative velocities of galaxies. The new definition of the local supercluster subsumes the prior defined local supercluster, the Virgo Supercluster, as an appendage.
Follow-up studies suggest that the Laniakea Supercluster is not gravitationally bound. It will disperse rather than continue to maintain itself as an overdensity relative to surrounding areas.