enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Hubble volume - Wikipedia

    en.wikipedia.org/wiki/Hubble_volume

    In cosmology, a Hubble volume (named for the astronomer Edwin Hubble) or Hubble sphere, Hubble bubble, subluminal sphere, causal sphere and sphere of causality is a spherical region of the observable universe surrounding an observer beyond which objects recede from that observer at a rate greater than the speed of light due to the expansion of ...

  3. Cosmological horizon - Wikipedia

    en.wikipedia.org/wiki/Cosmological_horizon

    Hubble radius, Hubble sphere (not to be confused with a Hubble bubble), Hubble volume, or Hubble horizon is a conceptual horizon defining the boundary between particles that are moving slower and faster than the speed of light relative to an observer at one given time. Note that this does not mean the particle is unobservable; the light from ...

  4. Observable universe - Wikipedia

    en.wikipedia.org/wiki/Observable_universe

    The light from the smallest, most redshifted galaxies originated nearly 13.8 billion years ago. The comoving distance from Earth to the edge of the observable universe is about 14.26 gigaparsecs (46.5 billion light-years or 4.40 × 10 26 m) in any direction.

  5. List of extrasolar candidates for liquid water - Wikipedia

    en.wikipedia.org/wiki/List_of_extrasolar...

    * Gas giant likely has no surface, liquid water if present could only be on a large satellite (none known) * density implies water in atmosphere, but none found yet * Possible class II ("water cloud") or class III ("clear") atmosphere planet [12] Gliese 581 c [citation needed] Gliese 581: 5.5 700–1000 20 7–11 12.9 2007 * Not in the CHZ

  6. Hubble's law - Wikipedia

    en.wikipedia.org/wiki/Hubble's_law

    The Hubble length or Hubble distance is a unit of distance in cosmology, defined as cH −1 — the speed of light multiplied by the Hubble time. It is equivalent to 4,420 million parsecs or 14.4 billion light years. (The numerical value of the Hubble length in light years is, by definition, equal to that of the Hubble time in years.)

  7. Astronomical spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Astronomical_spectroscopy

    The Star-Spectroscope of the Lick Observatory in 1898. Designed by James Keeler and constructed by John Brashear.. Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, ultraviolet, X-ray, infrared and radio waves that radiate from stars and other celestial objects.

  8. Orders of magnitude (volume) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(volume)

    Volume of the bright inner nebula of the Cat's Eye Nebula [16] 5.5 × 10 46: The volume of a Bok globule like Barnard 68 [19] [20] 4.4 × 10 47: The volume of a Bok globule one light year across [19] [20] 8.47 × 10 47: One cubic light-year ~1.7 × 10 48: Volume of the Oort Cloud, assuming a radius of 50 000 AU ~1.6 × 10 49: Volume of the ...

  9. Cosmic inflation - Wikipedia

    en.wikipedia.org/wiki/Cosmic_inflation

    Around 1930, Edwin Hubble discovered that light from remote galaxies was redshifted; the more remote, the more shifted.This implies that the galaxies are receding from the Earth, with more distant galaxies receding more rapidly, such that galaxies also recede from each other.