galactic halo


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galactic halo

See Galaxy. See also dark halo.

galactic halo

[gə′lak·tik ′hā·lō]
(astronomy)
The spherical distribution of oldest stars that are centered about the galactic center of the Milky Way Galaxy.
References in periodicals archive ?
Beaten just over three lengths into fourth, Galactic Halo fell a little short on that occasion at Wolverhampton but should be sharper for the experience.
General topics include the galactic halo, high velocity clouds and satellites; the disk-halo interface; outflows, starbursts and fountains; and extra-planar gas at intermediate and high redshift.
This uniformity challenges the view that the whole galactic halo formed from the successive swallowings of smaller stellar systems with independent evolutionary histories.
Future studies will use the ring as a tracer for the distribution of dark matter throughout our galactic halo.
Their work suggests that the Milky Way started out surrounded by many more globular clusters than the 160 or so known today, and that many or most have already been pulled apart and their stars strewn throughout the galactic halo.
This type of particle might inhabit a spherical region known as the galactic halo, encompassing our galaxy.
However, it has recently been found that some microquasars formed in the galactic halo, probably when the Milky Way itself was still taking shape.
Some sort of activity "is building up and breaking open a hole in the plane of our galaxy and pouring gas into the galactic halo," Dermer asserts.
Globular clusters formed early in the history of the Milky Way, yet Arp 2 and Terzan 7 are a pair of enigmatically young globulars residing in the galactic halo.
Key goals include measuring the abundance of deuterium throughout the universe and studying the hot interstellar medium and galactic halo.
Constrained by the cold, relatively dense gas that pervades the midplane of the galaxy, the expanding supernova "bubble" was channeled upward and outward, creating a narrow pillar of fast-flowing atoms that culminated in a broad, curling cap once it reached the hot but rarefied galactic halo.
The 150 or so globulars surviving today are probably just a small fraction of those that once populated the galactic halo.