English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

On 13 August 2002, during a substorm, Cluster encountered two earthward movingflux ropes (FR) in the central magnetotail. The first FR was observed duringthe expansion phase of the substorm, and the second FR during the recoveryphase. In the conjugate ionospheric region in Northern Fennoscandia, theionospheric equivalent currents were observed by the MIRACLE network and theauroral evolution was monitored by the Wideband Imaging Camera (WIC) on-boardthe IMAGE satellite. Extending the study of Amm et al. (2006), we examine andcompare the possible ionospheric signatures associated with the two FRs.Amm et al. studied the first event in detail and found that theionospheric footprint of Cluster coincided with a region of downwardfield-aligned current. They suggested that this region of downward current,together with a trailing region of upward current further southwestward,might correspond to the ends of the FR. Unlike during the first FR, however,we do not see any clear ionospheric features associated with the second one.In the GSM xy-plane, the first flux rope axis was tilted with respect tothe y-direction by 29°, while the second flux rope axis wasalmost aligned in the y-direction, with an angle of 4° only.It is possible that due to the length and orientation of the second FR, anyionospheric signatures were simply mapped outside the region covered by theground-based instruments. We suggest that the ground signatures of a FRdepend on the orientation and the length of the structure

Ionospheric signatures during a magnetospheric flux rope event