When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Cosmological horizon - Wikipedia

    en.wikipedia.org/wiki/Cosmological_horizon

    It represents the boundary between the observable and the unobservable regions of the universe, so its distance at the present epoch defines the size of the observable universe. Due to the expansion of the universe, it is not simply the age of the universe times the speed of light, as in the Hubble horizon, but rather the speed of light ...

  3. Observable universe - Wikipedia

    en.wikipedia.org/wiki/Observable_universe

    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. The observable universe is thus a sphere with a diameter of about 28.5 gigaparsecs [27] (93 billion light-years or 8.8 × 10 26 m). [28]

  4. Cosmology - Wikipedia

    en.wikipedia.org/wiki/Cosmology

    The Hubble eXtreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed at that time. Except for the few stars in the foreground (which are bright and easily recognizable because only they have diffraction spikes), every speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is ...

  5. Particle horizon - Wikipedia

    en.wikipedia.org/wiki/Particle_horizon

    Rather, the conformal time is the amount of time it would take a photon to travel from where we are located to the furthest observable distance, provided the universe ceased expanding. As such, η 0 {\displaystyle \eta _{0}} is not a physically meaningful time (this much time has not yet actually passed); though, as we will see, the particle ...

  6. Cosmography - Wikipedia

    en.wikipedia.org/wiki/Cosmography

    In astrophysics, the term "cosmography" is beginning to be used to describe attempts to determine the large-scale matter distribution and kinematics of the observable universe, dependent on the Friedmann–Lemaître–Robertson–Walker metric but independent of the temporal dependence of the scale factor on the matter/energy composition of the Universe.

  7. How astronomers used gravitational lensing to discover 44 new ...

    www.aol.com/astronomers-discovered-44-stars...

    The most powerful telescope to be launched into space has made history by detecting a record number of new stars in a distant galaxy. NASA's James Webb Space Telescope, history's largest and most ...

  8. How close is humanity to self-destruction? Doomsday Clock ...

    www.aol.com/close-humanity-self-destruction...

    The time on the symbolic clock was set at 90 seconds to midnight, the same as in 2023. Prior to that it had stood at 100 seconds to midnight, closer to destruction than at any point since it was ...

  9. Talk:Observable universe/Archive 1 - Wikipedia

    en.wikipedia.org/wiki/Talk:Observable_universe/...

    "The observable universe is a phrase used to distinguish the extent of the universe observable to an Earth-based astronomer from the actual and unobservable current extent of the universe. Because light travels at a finite velocity (300,000 Km/s) we observe distant objects not as they are now but as they were when the light left them.