uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Heavy ion escape from Mars, influence from solar wind conditions and crustal magnetic fields
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Swedish Institute of Space Physics, Uppsala Division.
Show others and affiliations
2011 (English)In: Icarus (New York, N.Y. 1962), ISSN 0019-1035, E-ISSN 1090-2643, Vol. 215, no 2, 475-484 p.Article in journal (Refereed) Published
Abstract [en]

We have used more than 4 years of Mars Express ion data to estimate the escape of heavy ions (O(1)(+) O(2)(+) and CO(2)(+)) from Mars. To take the limited field of view of the instrument into account, the data has been binned into spatial bins and angular bins to create average distribution functions for different positions in the near Mars space. The net escape flux for the studied low solar activity period, between May 2007 and May 2011, is 2.0 +/- 0.2 x 10(24) s(-1). The escape has been calculated independently for four different quadrants in the Y(MSO) - Zmso plane, south, dusk, north and dawn. Escape is highest from the northern and dusk quadrants, 0.6 +/- 0.1 x 10(24) s(-1), and smallest from the south and dawn quadrants, 0.4 +/- 0.1 x 10(24) s(-1). The flux ratio of molecular (O(2)(+) and CO(2)())(+) to 0 ions is 0.9 +/- 0.1, averaged over all quadrants. The flux difference between the north and south quadrants is statistically significant, and is presumed to be due to the presence of significant crustal magnetic fields in the southern hemisphere, reducing the outflow. The difference between the dawn and dusk quadrants is likely due to the magnetic tension associated with the nominal Parker angle spiral, which should lead to higher average magnetic tension on the dusk side. The escape increases during periods of high solar wind flux and during times when co-rotating interaction regions (CIR) affect Mars. In the latter case the increase is a factor 2.4-2.9 as compared to average conditions.

Place, publisher, year, edition, pages
2011. Vol. 215, no 2, 475-484 p.
Keyword [en]
Ionospheres, Mars, Atmosphere, Solar wind
National Category
Physical Sciences
URN: urn:nbn:se:uu:diva-160726DOI: 10.1016/j.icarus.2011.08.003ISI: 000295432400003OAI: oai:DiVA.org:uu-160726DiVA: diva2:453105
Available from: 2011-11-01 Created: 2011-10-31 Last updated: 2011-11-01Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Edberg, Niklas J. T.
By organisation
Swedish Institute of Space Physics, Uppsala Division
In the same journal
Icarus (New York, N.Y. 1962)
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 125 hits
ReferencesLink to record
Permanent link

Direct link