100 yottametres
Encyclopedia
To help compare different orders of magnitude, this page lists distance
Distance
Distance is a numerical description of how far apart objects are. In physics or everyday discussion, distance may refer to a physical length, or an estimation based on other criteria . In mathematics, a distance function or metric is a generalization of the concept of physical distance...

s greater than 100 Ym (1026 m
Metre
The metre , symbol m, is the base unit of length in the International System of Units . Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole , its definition has been periodically refined to reflect growing knowledge of metrology...

 or 11,000 million light years). At this scale, expansion of the universe
Universe
The Universe is commonly defined as the totality of everything that exists, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature...

 becomes significant. Distance of these objects are derived from their measured redshift
Redshift
In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum...

s, which depends on the cosmological
Physical cosmology
Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of the universe and is concerned with fundamental questions about its formation and evolution. For most of human history, it was a branch of metaphysics and religion...

 models used.

Distances shorter than 100 Ym
  • 130 Ym — redshift 6.41 — 13,000 million light years — Light travel distance (LTD) to the quasar
    Quasar
    A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...

     SDSS J1148+5251
  • 130 Ym — redshift 1000 — 13,700 million light years — Distance (LTD) to the source of the cosmic microwave background radiation
    Cosmic microwave background radiation
    In cosmology, cosmic microwave background radiation is thermal radiation filling the observable universe almost uniformly....

    ; radius of the observable universe
    Universe
    The Universe is commonly defined as the totality of everything that exists, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature...

     measured as a LTD
  • 260 Ym — 27,400 million light years — Diameter of the observable universe (double LTD)
  • 440 Ym — 46,000 million light years — Radius of the universe measured as a comoving distance
    Comoving distance
    In standard cosmology, comoving distance and proper distance are two closely related distance measures used by cosmologists to define distances between objects...

    .
  • 590 Ym — 62,000 million light years — Cosmological event horizon
    Event horizon
    In general relativity, an event horizon is a boundary in spacetime beyond which events cannot affect an outside observer. In layman's terms it is defined as "the point of no return" i.e. the point at which the gravitational pull becomes so great as to make escape impossible. The most common case...

    : the largest comoving distance from which light will ever reach us (the observer) at any time in the future
  • >>1,000 Ym (1 kYm in older usage) — Size of universe beyond the cosmic light horizon
    Observable universe
    In Big Bang cosmology, the observable universe consists of the galaxies and other matter that we can in principle observe from Earth in the present day, because light from those objects has had time to reach us since the beginning of the cosmological expansion...

    , depending on its curvature; if it is zero (i.e. the universe is spatially flat), the value is infinite (see shape of the Universe
    Shape of the Universe
    The shape of the universe is a matter of debate in physical cosmology over the local and global geometry of the universe which considers both curvature and topology, though, strictly speaking, it goes beyond both...

    )

This series on orders of magnitude does not have a range of longer distances.

External links

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