Journal cover Journal topic
Annales Geophysicae Sun, Earth, planets, and planetary systems An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/angeo-2018-55
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Regular paper
11 Jun 2018
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Annales Geophysicae (ANGEO).
Sporadic Aurora near Geomagnetic Equator: In the Philippines, on 27 October 1856
Hisashi Hayakawa1,2, José M. Vaquero3, and Yusuke Ebihara4,5 1Graduate School of Letters, Osaka University, Toyonaka, 5600043, Japan
2JSPS Research Fellow, Tokyo, 1020083, Japan
3Departamento de Física, Universidad de Extremadura, E-06800 Mérida, Spain
4Research Institute for Sustainable Humanosphere, Kyoto University, Uji, 6100011, Japan
5Unit of Synergetic Studies for Space, Kyoto University, Kyoto, 6068306, Japan
Abstract. While low latitude auroral displays are normally considered to be a manifestation of magnetic storms of considerable size, Silverman (2003, JGR, 108, A4) reported numerous sporadic auroras which appear locally at relatively low magnetic latitudes during times of just moderate magnetic activity. Here, a case study is presented of an aurora near the geomagnetic equator based on a report from the Philippine Islands on 27 October 1856. An analysis of this report shows it to be consistent with the known cases of sporadic aurorae except for its considerably low magnetic latitude. The record also suggests that extremely low-latitude aurora is not always accompanied with large magnetic storms. The description of its brief appearance leads to a possible physical explanation based on an ephemeral magnetospheric disturbance provoking this sporadic aurora.
Citation: Hayakawa, H., Vaquero, J. M., and Ebihara, Y.: Sporadic Aurora near Geomagnetic Equator: In the Philippines, on 27 October 1856, Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2018-55, in review, 2018.
Hisashi Hayakawa et al.
Hisashi Hayakawa et al.
Hisashi Hayakawa et al.

Viewed

Total article views: 155 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
126 25 4 155 2 3

Views and downloads (calculated since 11 Jun 2018)

Cumulative views and downloads (calculated since 11 Jun 2018)

Viewed (geographical distribution)

Total article views: 155 (including HTML, PDF, and XML)

Thereof 154 with geography defined and 1 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 21 Jun 2018
Publications Copernicus
Download
Short summary
We provide a case report of the low latitude aurora near geomagnetic equator on 27 October 1856. This aurora occurred during a moderate geomagnetic disturbance and is considered sporadic aurora which appears in relatively low magnetic latitude in a limited geographical extent. The report shows a limited duration of this phenomenon and we considered the physical nature of sporadic aurora accordingly.
We provide a case report of the low latitude aurora near geomagnetic equator on 27 October 1856....
Share