In astronomy, voids are the empty spaces between filaments, the largest-scale structures in the Universe, that contain very few, or no, galaxies. Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study In Physical cosmology, filaments are the largest known structures in the Universe, thread-like structures with a typical length of 50 to 80 ''h''-1 The Universe is defined as everything that Physically Exists: the entirety of Space and Time, all forms of Matter, Energy Voids typically have a diameter of 11 to 150 Mpc; particularly large voids, defined by the absence of rich superclusters, are sometimes called supervoids. History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 Superclusters are large groupings of smaller galaxy groups and clusters, and are among the largest structures of the Cosmos. Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe. 
List of voids
A 1994 census lists a total of 27 supervoids with a distance of up to 740 Mpc. Year 1994 ( MCMXCIV) was a Common year starting on Saturday (link will display full 1994 Gregorian calendar) 
Not shown in the above chart:
- Capricornus Void
- The Eridanus Supervoid, reported on 24 August 2007 by the NRAO from Very Large Array Sky Survey data, is much larger than these, being about 300 h-1Mpc in diameter and 1800–3000 h-1 Mpc distant. The Southern Local Supervoid is a tremendously large nearly-empty region of space, devoid of galaxies, known as a void. The Boötes void is a tremendously large approximately spherically shaped nearly-empty region of space, devoid of galaxies. The Northern Local Supervoid is a tremendously large region of space devoid of galaxies known as a void. In 2004 the Wilkinson Microwave Anisotropy Probe (WMAP mapped out a region in the Eridanus Constellation which had Cosmic microwave background radiation (CMB that Events 49 BC - Julius Caesar 's General Gaius Scribonius Curio is defeated in the Second Battle of the Bagradas River Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. The National Radio Astronomy Observatory (NRAO is a Federally Funded Research and Development Center of the United States National Science Foundation operated The Very Large Array ( VLA) is a Radio astronomy Observatory located on the Plains of San Augustin, between the towns of Magdalena It also corresponds to a cold spot in the cosmic microwave background. In 2004 the Wilkinson Microwave Anisotropy Probe (WMAP mapped out a region in the Eridanus Constellation which had Cosmic microwave background radiation (CMB that 
The universe within 1 billion light-years (307 Mpc) of Earth, showing local superclusters
and voids. Superclusters are large groupings of smaller galaxy groups and clusters, and are among the largest structures of the Cosmos.
- ^ U. Lindner, J. Einasto, M. Einasto, W. Freudling, K. Fricke, E. Tago (1995). "The Structure of Supervoids I: Void Hierarchy in the Northern Local Supervoid The structure of supervoids. I. Void hierarchy in the Northern Local Supervoid". Astron. Astrophys. 301.
- ^ Einasto, M (1994-07-15), “The Structure of the Universe Traced by Rich Clusters of Galaxies”, Monthly Notices of the Royal Astronomical Society 269, <http://adsabs.harvard.edu/abs/1994MNRAS.269..301E>
- ^ To the center of the void
- ^ This is the diameter of the largest sphere one can describe inside the void that contains no superclusters. Monthly Notices of the Royal Astronomical Society (MNRAS is one of the world's leading Scientific journals in Astronomy and Astrophysics. Some voids have an elongated shape, so this diameter may underrepresent the size of some voids.
- ^ "Astronomers Find Enormous Hole in the Universe". National Radio Astronomy Observatory Press release, retrieved 24 August 2007. The National Radio Astronomy Observatory (NRAO is a Federally Funded Research and Development Center of the United States National Science Foundation operated
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