Plasma observations during the Mars atmospheric "plume" event of March-April 2012
2016 (English)In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 121, no 4, 3139-3154 p.Article in journal (Refereed) PublishedText
We present initial analyses and conclusions from plasma observations made during the reported "Mars plume event" of March-April 2012. During this period, multiple independent amateur observers detected a localized, high-altitude "plume" over the Martian dawn terminator, the cause of which remains to be explained. The estimated brightness of the plume exceeds that expected for auroral emissions, and its projected altitude greatly exceeds that at which clouds are expected to form. We report on in situ measurements of ionospheric plasma density and solar wind parameters throughout this interval made by Mars Express, obtained over the same surface region but at the opposing terminator. Measurements in the ionosphere at the corresponding location frequently show a disturbed structure, though this is not atypical for such regions with intense crustal magnetic fields. We tentatively conclude that the formation and/or transport of this plume to the altitudes where it was observed could be due in part to the result of a large interplanetary coronal mass ejection (ICME) encountering the Martian system. Interestingly, we note that the only similar plume detection in May 1997 may also have been associated with a large ICME impact at Mars.
Place, publisher, year, edition, pages
2016. Vol. 121, no 4, 3139-3154 p.
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:uu:diva-300978DOI: 10.1002/2015JA022023ISI: 000379960300022OAI: oai:DiVA.org:uu-300978DiVA: diva2:954838
FunderSwedish National Space Board, DNR 162/14Swedish Research Council, DNR 621-2014-5526