Earth - 12,700 km in diameter - Our planet
Solar System - 4 light-years across - Our home planetary system. At this point, the Sun's gravity gives way to that of surrounding stars
Local Interstellar Cloud - 30 light-years across - Interstellar cloud of gas through which the Sun and a number of other stars are currently travelling
Milky Way Galaxy - 100,000 light-years across - Our home galaxy, composed of 200 billion to 400 billion stars and filled with the interstellar medium
Local Group - 3 megaparsecs across - Group of at least 47 galaxies. Dominated by Andromeda (the largest), The Milky Way and Triangulum; the remainder are small dwarf galaxies
Virgo Supercluster - 33 megaparsecs across - The supercluster of which our Local Group is a part; comprises roughly 100 galaxy groups and clusters
Pisces-Cetus Supercluster Complex - 300 megaparsecs across - The galaxy filament of which the Virgo Supercluster is a part
Observable Universe - 28,000 megaparsecs across - The large-scale structure of the universe consists of more than 100 billion galaxies, arranged in millions of superclusters, galactic filaments, and voids, creating a foam-like superstructure
Universe - Minimum of 28,000 megaparsecs - Beyond the observable universe lies the unobservable regions where no light from those regions has reached the Earth yet. No information is available about the region, as light is the fastest travelling medium of information. However, since there is no reason to suppose different natural laws, the universe is likely to contain more galaxies in the same foam-like superstructure
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