In our larger galactic neighborhood, going out for around one or two hundred million light-years, all of these clusters excepting Perseus-Pisces, which lies on the other side of a nearby void appear to have filaments with galaxies and galactic groups between them. This is the collection of matter that we refer to as Laniakea: our local supercluster. It links up our own massive cluster, the Virgo cluster, with the Centaurus cluster, the Great Attractor, the Norma Cluster and many others.
It's a beautiful idea that represents structures on scales larger than a visual inspection would reveal. But there's a problem with the idea of Laniakea in particular and with superclusters in general: these are not real, bound structures, but only apparent structures that are currently in the process of dissolving away entirely.
In between the great clusters and filaments of the Universe are great cosmic voids, some of which The long-held idea that the Universe is held together by structures spanning many hundreds of millions of light-years, these ultra-large superclusters, has now been settled, and these enormous web-like features are destined to be torn apart by the Universe's expansion. Our Universe isn't just a race between an initial expansion and the counteracting gravitational force caused by matter and radiation.
In addition, there's also a positive form of energy that's inherent to space itself: dark energy. It causes the recession of distant galaxies to speed up as time goes on. If there were no dark energy, Laniakea would most certainly be real. Unfortunately, dark energy became the dominant factor in our Universe's evolution approximately 6 billion years ago, and the various components of the Laniakea supercluster are already accelerating away from one another. Every component of Laniakea, including every independent group and cluster mentioned in this article, is not gravitationally bound to any other.
On larger scales, nearby galaxies, groups, and clusters may appear to be associated with it, but are being driven apart from this cluster due to dark energy; superclusters are only apparent structures.
All superclusters that we've ever identified are not only gravitationally unbound from one another, but they themselves are not gravitationally bound structures.
The individual groups and clusters within a supercluster are unbound, meaning that as time goes on, each structure presently identified as a supercluster will eventually dissociate. For our own corner of the Universe, the Local Group will never merge with the Virgo cluster, the Leo I group, or any structure larger than our own. They are not bound together, and they will never become so.
In fact, if a structure had not already accumulated enough mass 6 billion years ago to become bound, when dark energy first dominated the Universe's expansion, it never will.
Billions of years from now, the individual supercluster components will be torn apart by the Universe's expansion, forever adrift as lonesome islands in the great cosmic ocean.
This is a BETA experience. You may opt-out by clicking here. More From Forbes. Nov 11, , am EST. Nov 10, , pm EST. Nov 9, , pm EST. Nov 9, , am EST. Edit Story. Ethan Siegel Senior Contributor. Groups Why Join? Astronomy Day. The Complete Star Atlas. The Virgo Cluster, which sits 65 million light-years away, is near the center of our Local Supercluster; their coincident positions are why it is called the Virgo Supercluster. Our home galaxy, the Milky Way, along with a few dozen of its neighbors, belongs to a group of galaxies, just a small knot in a larger cosmic network.
To understand how our local environs fit into the cosmos at the largest scales, definitions are surprisingly important. All in a name University of Hawaii astronomer R. Maffei 1 and 2 were discovered by Paolo Maffei in the s, using infrared light.
The optical light in these galaxies is heavily obscured by gas and dust. They belong to galaxy groups within our larger Local Supercluster. Follow the motion As detection and analysis techniques improved, however, astronomers realized the Virgo Supercluster was not a gravitationally bound object. Centaurus A NGC is one of the brightest galaxies in the sky. One for the history books So, what becomes of the previously known Local, or Virgo, Supercluster?
The Virgo Supercluster, centered on the Virgo Cluster of galaxies about 65 million light-years away, contains smaller groups and clusters of galaxies, including the Local Group. This illustration shows groups with at least three large galaxies. The size of each bubble represents the number of galaxies in that group. Groups and clusters are shown at their relative distances from the Local Group.
This visualization shows a slice of the Laniakea Supercluster. Color represents density, with red showing greater densities of galaxies and blue showing voids with little material. White lines show the flow of galaxies white dots into the supercluster, which is bounded by orange. Anything within the boundaries of the supercluster feels its gravity and will fall toward the center over time.
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Want to leave a comment? Only registered members of Astronomy. Registration is FREE and only takes a couple minutes. Login or Register now. Most recent Oldest to newest. Long trips to space linked to possible brain damage. Scientists even have a name for the colossal galactic group: Laniakea, Hawaiian for "immeasurable heaven. The scientists responsible for the new 3D map suggest that the newfound Laniakea supercluster of galaxies may even be part of a still-larger structure they have not fully defined yet.
Galaxies are not spread randomly throughout the universe. Instead, they clump in groups, such as the one Earth is in, the Local Group, which contains dozens of galaxies. In turn, these groups are part of massive clusters made up of hundreds of galaxies, all interconnected in a web of filaments in which galaxies are strung like pearls.
The colossal structures known as superclusters form at the intersections of filaments.
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