galactic halo

galactic halo
In astronomy, a nearly spherical volume of thinly scattered stars, globular clusters, and tenuous gas observed surrounding spiral galaxies.

It may extend far beyond the disk and contain most of the galaxy's mass. The halo of the Milky Way Galaxy is thought to have a radius greater than 100,000 light-years and to be predominantly composed of dark matter.

* * *

      in astronomy, nearly spherical volume of thinly scattered stars, globular clusters of stars, and tenuous gas observed surrounding spiral galaxies, including the Milky Way (Milky Way Galaxy)—the galaxy in which the Earth is located. The roughly spherical halo of the Milky Way is thought to have a radius of some 50,000 light-years (about 5 × 1017 kilometres), and its gas is a source of radio emission, particularly at the 21-centimetre wavelength (see 21-centimetre radiation).

* * *


Universalium. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • galactic halo — noun (astronomy) An aggregation of stars, globular clusters, dust and gas surrounding a galaxy • • • Main Entry: ↑galaxy …   Useful english dictionary

  • Galactic halo — The term galactic halo is used to denote an extended, roughly spherical component of a galaxy, which extends beyond the main, visible component. It can refer to any of several distinct components which share these properties: * the galactic… …   Wikipedia

  • Halo — may refer to: *Halo (religious iconography), a ring of light that surrounds an object in religious iconography *Halo (optical phenomenon), a ring of light that surrounds an object *Halo (medicine), used to immobilize cervical neck (spinal)… …   Wikipedia

  • Galactic corona — The terms galactic corona and gaseous corona have been used in the first decade of the twenty first century to describe a hot, ionised, gaseous component in the Galactic halo of the Milky Way. A similar body of very hot and tenuous gas in the… …   Wikipedia

  • Galactic tide — A galactic tide is a tidal force subjected on objects by the gravitational field of a galaxy such as the Milky Way. Particular areas of interest concerning galactic tides include galactic collisions, the disruption of dwarf or satellite galaxies …   Wikipedia

  • Halo (Astronomie) — Der Halo (von griechisch hálos »Lichthof«) einer Galaxie ist ein annähernd kugelförmiger Bereich, der größer ist als die Galaxie selber und in dessen Zentrum sie eingebettet ist. Im Halo befinden sich Kugelsternhaufen und wenige, meistens… …   Deutsch Wikipedia

  • Galactic coordinate system — Artist s depiction of the Milky Way galaxy, showing the galactic longitude relative to the sun. The galactic coordinate system (GCS) is a celestial coordinate system which is centered on the Sun and is aligned with the apparent center of the… …   Wikipedia

  • galactic — /geuh lak tik/, adj. 1. Astron. a. of or pertaining to a galaxy. b. of or pertaining to the Milky Way. 2. immense; huge; vast: a problem of galactic proportions. 3. Physiol. pertaining to or stimulating the secretion of milk. [1830 40; < Gk… …   Universalium

  • Galactic astronomy — is the study of our own Milky Way galaxy and all its contents. This is in contrast to extragalactic astronomy, which is the study of everything outside our galaxy, including all other galaxies.Galactic astronomy is that branch of astronomy which… …   Wikipedia

  • Galactic empire — Galactic empires are a common theme in science fiction. Many authors have either used a galaxy spanning empire as background, or written about the growth or decline of such an empire. The capital of a galactic empire is frequently a core world or …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”