Dusk-brightening event in Saturn's H3+ aurora

Tom Stallard*, Steve Miller, Makenzie Lystrup, Nicholas Achilleos, Chris Arridge, Michele Dougherty

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

We report on a unique dusk-brightening event within Saturn's aurorae. Measurements of the H+3 infrared aurora using the CSHELL instrument on NASA's Infrared Telescope Facility (IRTF), made in 2005 December, show an auroral intensity structure unlike anything previously detected. The aurora has a significantly brighter dusk sector over three Earth nights, a period in excess of 5 Saturnian days, suggesting a consistent source for this emission, stable in position within the magnetosphere. However, unlike previously detected dawn-brightening events, the overall auroral brightness remains low and the ion wind structure appears unaffected. Using the location of magnetopause crossings as a proxy for the solar wind pressure, the solar wind appears to be exceptionally rarefied. This leads us to conclude that the dusk-brightening event is strongly linked with the unusual solar wind conditions at the time of the observations.
Original languageEnglish
Pages (from-to)L203-L206
Number of pages4
JournalAstrophysical Journal Letters
Volume673
Issue number2
DOIs
Publication statusPublished - 1 Feb 2008
Externally publishedYes

Keywords

  • atmospheric effects
  • infrared : solar system
  • planets and satellites : individual (Saturn)

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