Astrophysical plasma

Lagoon Nebula is a large, low-density cloud of partially ionized gas.[1]

Astrophysical plasma is plasma outside of the Solar System. It is studied as part of astrophysics and is commonly observed in space.[2] The accepted view of scientists is that much of the baryonic matter in the universe exists in this state.[3]

When matter becomes sufficiently hot and energetic, it becomes ionized and forms a plasma. This process breaks matter into its constituent particles which includes negatively charged electrons and positively charged ions.[4] These electrically charged particles are susceptible to influences by local electromagnetic fields. This includes strong fields generated by stars, and weak fields which exist in star forming regions, in interstellar space, and in intergalactic space.[5] Similarly, electric fields are observed in some stellar astrophysical phenomena, but they are inconsequential in very low-density gaseous media.

Astrophysical plasma is often differentiated from space plasma, which typically refers to the plasma of the Sun, the solar wind, and the ionospheres and magnetospheres of the Earth and other planets.[6][7][8][9][10][11][12]

## Observing and studying astrophysical plasma

[edit]

Plasmas in stars can both generate and interact with magnetic fields, resulting in a variety of dynamic astrophysical phenomena. These phenomena are sometimes observed in spectra due to the Zeeman effect. Other forms of astrophysical plasmas can be influenced by preexisting weak magnetic fields, whose interactions may only be determined directly by polarimetry or other indirect methods.[5] In particular, the intergalactic medium, the interstellar medium, the interplanetary medium and solar winds consist of diffuse plasmas.

## Possible related phenomena

[edit]

Scientists are interested in active galactic nuclei because such astrophysical plasmas could be directly related to the plasmas studied in laboratories.[13] Many of these phenomena seemingly exhibit an array of complex magnetohydrodynamic behaviors, such as turbulence and instabilities.[2]

In Big Bang cosmology, the entire universe was in a plasma state prior to recombination.[14]

## Early history

[edit]

Norwegian explorer and physicist Kristian Birkeland predicted that space is filled with plasma. He wrote in 1913:

> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. We have assumed that each stellar system through its evolution throws off electric corpuscles into space.

Birkeland assumed that most of the mass in the universe should be found in "empty" space.[15]

## References

[edit]

1. ^ "Sneak Preview of Survey Telescope Treasure Trove". ESO Press Release. Retrieved 23 January 2014.
2. ^ a b "Study sheds light on turbulence in astrophysical plasmas: Theoretical analysis uncovers new mechanisms in plasma turbulence". MIT News. December 2017. Retrieved 2018-02-20.
3. ^ Chiuderi, C.; Velli, M. (2015). "Particle Orbit Theory". Basics of Plasma Astrophysics. UNITEXT for Physics. p. 17\. Bibcode:2015bps..book.....C. doi:10.1007/978-88-470-5280-2_2. ISBN 978-88-470-5280-2.
4. ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006-) "Ionization". doi:10.1351/goldbook.I03183
5. ^ a b Lazarian, A.; Boldyrev, S.; Forest, C.; Sarff, P. (2009). "Understanding of the role of magnetic fields: Galactic perspective". Astro2010: The Astronomy and Astrophysics Decadal Survey. 2010: 175. arXiv:0902.3618. Bibcode:2009astro2010S.175L.
6. ^ "Space Physics Textbook". 2006-11-26. Archived from the original on December 18, 2008. Retrieved 2018-02-23.
7. ^ "The Solar Physics and Space Plasma Research Centre (SP2RC)". MIT News. Retrieved 2018-02-23.
8. ^ Owens, Mathew J.; Forsyth, Robert J. (2003). "The Heliospheric Magnetic Field". Living Reviews in Solar Physics. 10 (1): 5. arXiv:1002.2934. Bibcode:2013LRSP...10....5O. doi:10.12942/lrsp-2013-5. ISSN 2367-3648. S2CID 122870891.
9. ^ Nagy, Andrew F.; Balogh, André; Thomas E. Cravens; Mendillo, Michael; Mueller-Woodarg, Ingo (2008). Comparative Aeronomy. Springer. pp. 1–2\. ISBN 978-0-387-87824-9.
10. ^ Ratcliffe, John Ashworth (1972). An Introduction to the Ionosphere and Magnetosphere. CUP Archive. ISBN 978-0-521-08341-6.
11. ^ NASA Study Using Cluster Reveals New Insights Into Solar Wind, NASA, Greenbelt, 2012, p.1
12. ^ Cade III, William B.; Christina Chan-Park (2015). "The Origin of "Space Weather"". Space Weather. 13 (2): 99. Bibcode:2015SpWea..13...99C. doi:10.1002/2014SW001141.
13. ^ Berkowitz, Rachel (April 2018). "Lab experiments mimic the origin and growth of astrophysical magnetic fields". Physics Today. 71 (4): 20–22\. Bibcode:2018PhT....71d..20B. doi:10.1063/PT.3.3891.
14. ^ Peebles, P. J. E. (1968). "Recombination of the Primeval Plasma". Astrophysical Journal. 153: 1. Bibcode:1968ApJ...153....1P. doi:10.1086/149628.
15. ^ Birkeland, Kristian (1908). The Norwegian Aurora Polaris Expedition 1902–1903. New York and Christiania (now Oslo): H. Aschehoug & Co. p. 720. out-of-print, full text online.

## External links

[edit]

* "US / Russia Collaboration in Plasma Astrophysics"

Authority control databases: National |

* United States
* France
* BnF data
* Israel

|