The term galactic halo denotes a component of spiral galaxies, including our galaxy, the Milky Way, which extends further out than the disk, which is the most visible part of a spiral galaxy.

Galactic halo may mean:

• the galactic spheroid component - stars
• the galactic corona - some hot gas (ie. a plasma)
• the dark matter halo of a galaxy

The galactic spheroid and the dark matter halo are concentrated towards the centre of their galaxy, and are roughly spherically symmetric.

In an elliptical galaxy, there is no sharp transition between the body of the galaxy and the halo.

See also

• Galaxy formation and evolution
• Galactic coordinate system
• disc (galaxy)
• bulge (astronomy)
• galactic corona
• spiral arm

References

• Diemand, J. & Moore, B. & Stadel, J. (2005, January 27). Earth-mass dark-matter haloes as the first structures in the early universe. In Nature, 433, 389 – 391.

External links

• http://chandra.harvard.edu/photo/2006/n5746/

Galaxies

Halo galàctic | Halo (Astronomie) | Halo galactique | Alone galattico | Halo (astronomie) | Halo galaktyczne | Galaktické halo