this page, and at the bottom of the page offers online calculators that can be used to calculate the current proper distance to a distant object in a flat universe based on either the redshift z or the light travel time). The proper distance for a redshift of 8.2 would be about 9.2 Gpc, or about 30 billion light-years. Horizons The limit of observability in the universe is set by a set of cosmological horizons which limit—based on various physical constraints—the extent to which we can obtain information about various events in the universe. The most famous horizon is the particle horizon which sets a limit on the precise distance that can be seen due to the finite age of the universe. Additional horizons are associated with the possible future extent of observations (larger than the particle horizon owing to the expansion of space), an "optical horizon" at the surface of last scattering, and associated horizons with the surface of last scattering for neutrinos and gravitational waves. See also Notes References Further reading External links "Millennium Simulation" of structure forming – Max Planck Institute of Astrophysics, Garching, Germany Cosmology FAQ Forming Galaxies Captured In The Young Universe By Hubble, VLT & Spitzer Animation of the cosmic light horizon Inflation and the Cosmic Microwave Background by Charles Lineweaver Logarithmic Maps of the Universe List of publications of the 2dF Galaxy Redshift Survey The Universe Within 14 Billion Light Years – NASA Atlas of the Universe – Note, this map only gives a rough cosmographical estimate of the expected distribution of superclusters within the observable universe; very little actual mapping has been done beyond a distance of one billion light-years. Video: The Known Universe, from the American Museum of Natural History NASA/IPAC Extragalactic Database Cosmography of the Local Universe at irfu.cea.fr (17:35) (arXiv) There are about 1082 atoms in the observable universe – LiveScience, July 2021. Limits to knowledge about Universe – Forbes, May 2019. Physical cosmology Concepts in astronomy