Norma Arm
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The Norma Arm is a minor spiral arm of the
Orion-Cygnus Arm), which lies outside the Perseus Arm, or the Outer Arm, which is located farther away from the center of the Galaxy than the Cygnus Arm.[1] The Norma Arm begins 2.2 kpc from the Galactic Center,[2] and extends outward to a radius of 15.5±2.8 kpc. It is named for the Norma
constellation, through which the Arm as seen from Earth passes.
Like many other galaxies of similar type, the Milky Way consists of a large mass of stars shaped into the form of a relatively flat disc by gravity. The disc is rotating, with the dense central body of stars moving at greater speeds than those toward the rim of the disc. As a result, the pattern of stars within the Galaxy as viewed from directly above or below the disc has formed into a spiral.
Because of localised gravitational variations, the spiral pattern has itself formed several distinct 'spiral arms', where particularly large numbers of stars can be found.[1]
See also
References
| Location | Milky Way → Milky Way subgroup → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster → Local Hole → Observable universe → Universe Each arrow (→) may be read as "within" or "part of". |  | |||||
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