Galactic prominences on the rise

Science

Volumn 314, Issue 5796, 2006, Pages 70-71

  Morris, Mark ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

HUGE MOLECULAR LOOPS; MILKY WAY;

PLASMAS; SUN;

ASTROPHYSICS;

COSMOLOGY; SOLAR PHENOMENA;

ASTRONOMY; COSMOLOGICAL PHENOMENA; GAS; GRAVITY; MAGNETIC FIELD; PRIORITY JOURNAL; REVIEW;

EID: 33749591497     PISSN: 00368075     EISSN: 10959203     Source Type: Journal    
DOI: 10.1126/science.1133500     Document Type: Review

References (12)

1. Y. Fukui et al., Science 314, 106 (2006).
2. For comparison, our distance from the galactic center is ∼25,000 light-years.
3. E. N. Parker, Astrophys. J. 145, 811 (1966).
4. The buoyancy of the magnetic loop is augmented by the pressure of the "gas" of galactic cosmic rays. These essentially light-speed particles inflate the region encompassed by the loop.
5. B. G. Elmegreen, Astrophys. J. 253, 634 (1982).
6. Some relatively nearby magnetic structures lying well above the galactic plane have been interpreted as manifestations of the Parker instability, but these are more readily explained as compressed, magnetized shells lying at the surfaces of large, expanding bubbles in the interstellar medium caused by supernovae and other energy injection processes associated with massive star formation.
7. Without access to information about the velocity perpendicular to our line of sight, there is an ambiguity about whether this flow goes up or down, but the expectation from the Parker instability is that it goes toward the galactic plane.
8. G. Novak et al., Astrophys. J. 583, L83 (2003).
9. M. Morris, E. Serabyn, Annu. Rev. Astron. Astrophys. 34, 645 (1996).
10. The footpoints are strongly tied to the gas in the galactic plane, and they will therefore follow that gas as it slowly migrates inward toward the galactic center by losing angular momentum through a variety of processes, one of which is the torque exerted by these magnetic columns that the gas is dragging along.
11. F. Yusef-Zadeh, J. W. Hewitt, W. Cotton, Astrophys. J. Suppl. 155, 421 (2004).
12. I thank F. Coroniti for a thought-provoking discussion.